livescience--2020-10-31--Daylight saving time 2020: When we change our clocks and why

On Sunday , Nov. 1 , most Americans will push their clocks back an hour , as daylight saving time ( sometimes erroneously called daylight savings time ) comes to an end .
In March 2021 , daylight saving time will begin again and we 'll set our clocks forward by an hour in those regions that observe DST .
These fall and spring clock changes continue a long tradition started by Benjamin Franklin to conserve energy .
Here 's a look at when daylight saving time starts and ends during the year , its history , why we have @ @ @ @ @ @ @ facts about the time change .
• 5 Crazy Chapters in the History of Daylight Saving Time • Why Does Daylight Saving Time Start at 2 a.m. ?
• Tips : How to Survive the Time Change When does daylight saving time start and end ?
Historically , daylight saving time ( DST ) has begun in the summer months and ended right before winter , though the dates have changed over time as the U.S. government has passed new statutes , according to the U.S .
Naval Observatory ( USNO ) .
@ @ @ @ @ @ @ the United States on the second Sunday in March , when people move their clocks forward an hour at 2 a.m. local standard time ( so at 2 a.m. on that day , the clocks will then read 3 a.m. local daylight time ) .
Daylight saving time then ends on the first Sunday in November , when clocks are moved back an hour at 2 a.m. local daylight time ( so they will then read 1 a.m. local standard time ) .
In 2020 , DST will began on March 8 and @ @ @ @ @ @ @ , when you 'll set the clock back an hour and the cycle will begin again .
Daylight saving time in the U.S. will begin again on March 14 , 2021 , according to timeanddate.com .
Benjamin Franklin takes the honor ( or the blame , depending on your view of the time changes ) for coming up with the idea to reset clocks in the summer months as a way to conserve energy , according to David Prerau , author of `` Seize the Daylight : The Curious and Contentious Story of @ @ @ @ @ @ @ Mouth Press , 2005 ) .
By moving clocks forward , people could take advantage of the extra evening daylight rather than wasting energy on lighting .
At the time , Franklin was ambassador to Paris and so wrote a witty letter to the Journal of Paris in 1784 , rejoicing over his `` discovery '' that the sun provides light as soon as it rises .
Even so , DST did n't officially begin until more than a century later .
Germany established DST in May 1916 as a way to conserve @ @ @ @ @ @ @ rest of Europe came onboard shortly thereafter .
And in 1918 , the United States adopted daylight saving time .
Though President Woodrow Wilson wanted to keep daylight saving time after WWI ended , the country was mostly rural at the time and farmers objected , partly because it would mean they lost an hour of morning light .
( It 's a myth that DST was instituted to help farmers . )
And so daylight saving time was abolished until the next war brought it back into vogue .
At the start @ @ @ @ @ @ @ 1942 , President Franklin Roosevelt re-established daylight saving time year-round , calling it `` War Time . ''
Related : 5 crazy chapters in the history of daylight saving time After the war , a free-for-all system in which U.S. states and towns were given the choice of whether or not to observe DST led to chaos .
And in 1966 , to tame such `` Wild West '' mayhem , Congress enacted the Uniform Time Act .
That federal law meant that any state observing DST — and they did n't have @ @ @ @ @ @ @ had to follow a uniform protocol throughout the state in which daylight saving time would begin on the first Sunday of April and end on the last Sunday of October .
Then , in 2007 , the Energy Policy Act of 2005 went into effect , expanding the length of daylight saving time to the present timing .
Why do we still have daylight saving time ?
Fewer than 40 % of the world 's countries observe daylight saving time , according to timeanddate.com .
However , those who do observe DST take @ @ @ @ @ @ @ summer evenings .
That 's because the days start to get longer as Earth moves from the winter season to spring and summer , with the longest day of the year on the summer solstice .
During the summer season in each hemisphere , Earth , which revolves around its axis at an angle , is tilted directly toward the sun .
Related : Read more about the science of summer .
Regions farthest away from the equator and closer to the poles get the most benefit from the DST clock change , @ @ @ @ @ @ @ in sunlight throughout the seasons .
Research has also suggested that with more daylight in the evenings , there are fewer traffic accidents , as there are fewer cars on the road when it 's dark outside .
More daylight also could mean more outdoor exercise ( or exercise at all ) for full-time workers .
The nominal reason for daylight saving time has long been to save energy .
The time change was first instituted in the United States during World War I , and then reinstituted again during World War II @ @ @ @ @ @ @ effort .
During the Arab oil embargo , when Arab members of the Organization of Petroleum Exporting Countries ( OPEC ) stopped selling petroleum to the United States , Congress even enacted a trial period of year-round daylight saving time in an attempt to save energy .
But the evidence for energy savings is slim .
Brighter evenings may save on electric lighting , said Stanton Hadley , a senior researcher at Oak Ridge National Laboratory who helped prepare a report to Congress on extended daylight saving time in 2007 .
But lights @ @ @ @ @ @ @ , so lighting is responsible for a smaller chunk of total energy consumption than it was a few decades ago .
Heating and cooling probably matter more , and some places may need air-conditioning for the longer , hotter evenings of summer daylight saving time .
Hadley and his colleagues found that the four weeks of extra daylight saving time that went into effect in the United States in 2007 did save some energy , about half of a percent of what would have otherwise been used on each of those days .
@ @ @ @ @ @ @ of the entire months-long stretch of daylight saving could very well have the opposite effect .
A 1998 study in Indiana before and after implementation of daylight saving time in some counties found a small increase in residential energy usage .
Temporary changes in Australia 's daylight saving timing for the summer Olympics of 2000 also failed to save any energy , a 2007 study found .
Part of the trouble with estimating the effect of daylight saving time on energy consumption is that there are so few changes to the policy , @ @ @ @ @ @ @ Live Science .
The 2007 extension of daylight saving time allowed for a before-and-after comparison of only a few weeks ' time .
The changes in Indiana and Australia were geographically limited .
Ultimately , Hadley said , the energy question probably is n't the real reason the United States sticks with daylight saving time , anyway .
`` In the vast scheme of things , the energy saving is not the big driver , '' he said .
`` It 's people wanting to take advantage of that light time in the @ @ @ @ @ @ @ time ?
( And who does n't ? )
Most of the United States and Canada observe DST on the same dates with a few exceptions .
Hawaii and Arizona are the two U.S. states that do n't observe daylight saving time , though Navajo Nation , in northeastern Arizona , does follow DST , according to NASA .
And , every year there are bills put forth to get rid of DST in various states , as not everyone is keen on turning their clocks forward an hour .
In 2018 , @ @ @ @ @ @ @ called the Sunshine Protection Act ( a PDF of the legislation ) that would ask the U.S. Congress to exempt the state from the federal 1966 Uniform Time Act .
If approved , Florida would remain in DST year-round .
In order to allow Florida 's year-round DST , however , the U.S. Congress would have to amend the Uniform Time Act ( 15 U.S.C .
s. 260a ) to authorize states this allowance , according to The New York Times .
Congress has yet to approve the legislation , the South Florida @ @ @ @ @ @ @ of 2018 , California voted in favor of Proposition 7 that would attempt to repeal the annual clock changes .
Next , the state legislature needs to vote on the proposition , followed by the Congress , according to an article on Vox .
However , none of that happened , because the federal government did n't approve the time change , San Diego 's CBS8 reported .
Other states have also proposed exemptions from the federal time act .
For instance , Sen. Ryan Osmundson , R-Buffalo , introduced Senate Bill 206 @ @ @ @ @ @ @ February 2017 , which would exempt Montana from daylight saving time , keeping the state on standard time year-round , according to the bill .
Three bills put forth in 2017 in Texas aimed to abolish DST for good : House Bill 2400 , Senate Bill 238 and House Bill 95 , according to the broadcast company kxan .
Nebraskans may be off the hook for clock changes as well .
In January 2017 , state Sen. Lydia Brasch , a Republican of Bancroft , proposed a bill called LB309 to eliminate daylight @ @ @ @ @ @ @ to the bill .
Some regions of British Columbia and Saskatchewan do n't change their clocks .
These include the following areas in British Columbia : Charlie Lake , Creston ( East Kootenays ) , Dawson Creek , Fort St. John , and Taylor ; in Saskatchewan , only Creighton and Denare Beach observe DST , according to NASA .
Most of Europe currently observes daylight saving time , called `` summer time , '' which begins at 1 a.m. GMT on the last Sunday in March and ends ( winter time ) @ @ @ @ @ @ @ Sunday in October .
However , even the European Union may propose an end to clock changes , as a recent poll found that 84 % of 4.6 million people surveyed said they wanted to nix them , the Wall Street Journal reported .
If the lawmakers and member states agree , the EU members could decide to keep the EU in summer time or winter time , according to the WSJ .
The United Kingdom moved their clocks forward on March 29 , 2020 , and back again to standard time on @ @ @ @ @ @ @ government .
The DST-observing countries in the Southern Hemisphere — in Australia , New Zealand , South America and southern Africa — set their clocks forward an hour sometime during September through November and move them back to standard time during the March-April timeframe .
Australia , being such a big country ( the sixth-largest in the world ) , does n't follow DST uniformly : New South Wales , Victoria , South Australia , Tasmania and the Australian Capital Territory follow daylight saving , while Queensland , the Northern Territory ( Western @ @ @ @ @ @ @ the Australian government .
Clocks in the observing areas spring forward an hour at 2 a.m. local time on the first Sunday in October and push back an hour at 3 a.m. local daylight time on the first Sunday in April .
Russia instituted year-round daylight saving time in 2011 , or permanent `` summer time , '' which seemed dandy at first .
But in the depths of winter , sunrise occurred at 10 a.m. in Moscow and 11 a.m. in St. Petersburg , said David Prerau , author of `` Seize @ @ @ @ @ @ @ Story of Daylight Saving Time '' ( Basic Books , 2009 ) .
This meant Russians had to start their days in the cold , pitch-dark .
The permanent summer is coming to an end , however , as now Russian president Vladimir Putin abolished DST in 2014 , according to BBC News .
As such , the country will remain in `` winter time '' forever , or until another law is passed .
• Turns out , people tend to have more heart attacks on the Monday following the `` spring @ @ @ @ @ @ @ .
Researchers reporting in 2014 in the journal Open Heart , found that heart attacks increased 24 % on that Monday , compared with the daily average number for the weeks surrounding the start of DST .
• Before the Uniform Time Act was passed in the United States , there was a period in which anyplace could or could not observe DST , leading to chaos .
For instance , if one took a 35-mile bus ride from Moundsville , West Virginia , to Steubenville , Ohio , he or she would @ @ @ @ @ @ @ changes , according to Prerau .
At some point , Minneapolis and St. Paul were on different clocks .
• A study published in 2009 in the Journal of Applied Psychology showed that during the week following the `` spring forward '' into DST , mine workers got 40 minutes less sleep and had 5.7 % more workplace injuries than they did during any other days of the year .
• Pets notice the time change , as well .
Since humans set the routines for their fluffy loved ones , dogs and @ @ @ @ @ @ @ disrupted when , say , you bring their food an hour late or come to milk them later than usual , according to Alison Holdhus-Small , a research assistant at CSIRO Livestock Industries , an Australia-based research and development organization .
• The fact that the time changes at 2 a.m. at least in the U.S. , may have to do with practicality .
For instance , it 's late enough that most people are home from outings and setting the clock back an hour wo n't switch the date to `` yesterday @ @ @ @ @ @ @ early enough not to affect early shift workers and early churchgoers , according to the WebExhibits , an online museum .
This article was updated on Oct. 31 , 2020 .
Follow LiveScience.com on Facebook for interesting news and discoveries .

Daylight saving time begins on Sunday, March 12, 2023, when the clocks skip ahead an hour at 2 a.m. local time. The clocks will fall back again on Sunday, Nov. 5, 2023 at 2 a.m. local time, when daylight saving time (sometimes erroneously called daylight savings time) ends for the year. These fall and spring time changes continue a tradition started during World War I.
In 2022, the U.S. Senate overwhelmingly voted to make daylight savings time permanent, but the legislation stalled in the U.S. House. On March 2, 2023, U.S. Sen. Marco Rubio (R-FL) reintroduced the Sunshine Protection Act of 2023 to the 118th Congress.
Here's a look at when daylight saving time starts and ends during the year, so you know when to change your clock and not miss an important meeting. You'll also learn about the history of daylight saving time, why we have it now and some myths and interesting facts about the time change.
When does the time change?
Historically, daylight saving time (DST) has begun in the summer months and ended right before winter, though the dates have changed over time as the U.S. government has passed new statutes, according to the U.S. Naval Observatory (USNO).
So when does the time change? Starting in 2007, DST begins in the U.S. on the second Sunday in March, when people move their clocks forward an hour at 2 a.m. local standard time (so at 2 a.m. on that day, the clocks will then read 3 a.m. local daylight time). Daylight saving time then ends on the first Sunday in November, when clocks are moved back an hour at 2 a.m. local daylight time (so they will then read 1 a.m. local standard time).
Why did daylight saving time start?
Benjamin Franklin takes the honor (or the blame, depending on your view of the time changes) for coming up with the idea to reset clocks in the summer months as a way to conserve energy, according to David Prerau, author of "Seize the Daylight: The Curious and Contentious Story of Daylight Saving Time" (Thunder's Mouth Press, 2005). By moving clocks forward, people could take advantage of the extra evening daylight rather than wasting energy on lighting. At the time, Franklin was ambassador to Paris, and he wrote a witty letter to the Journal of Paris in 1784, rejoicing over his "discovery" that the sun provides light as soon as it rises.
Even so, DST didn't officially begin until more than a century later. Germany established DST in May 1916, as a way to conserve fuel during World War I. The rest of Europe came onboard shortly thereafter. And in 1918, the United States adopted daylight saving time.
President Woodrow Wilson, shown here, signed the Standard Time Act in 1918, establishing U.S. time zones and daylight saving time, which would begin on March 31. (Image credit: Topical Press Agency/Getty Images)
Though President Woodrow Wilson wanted to keep daylight saving time after WWI ended, the country was mostly rural at the time and farmers objected, partly because it would mean they lost an hour of morning light. (It's a myth that DST was instituted to help farmers.) And so daylight saving time was abolished until the next war brought it back into vogue. At the start of WWII, on Feb. 9, 1942, President Franklin Roosevelt re-established daylight saving time year-round, calling it "War Time."
After the war, a free-for-all system in which U.S. states and towns were given the choice of whether or not to observe DST led to chaos. And in 1966, to tame such "Wild West" mayhem, Congress enacted the Uniform Time Act. That federal law meant that any state observing DST — and they didn't have to jump on the DST bandwagon — had to follow a uniform protocol throughout the state in which daylight saving time would begin on the first Sunday of April and end on the last Sunday of October.
Then, in 2007, the Energy Policy Act of 2005 went into effect, expanding the length of daylight saving time to the present timing.
Why do we have daylight saving time?
Fewer than 40% of the world's countries observe daylight saving time, according to timeanddate.com. However, those who do observe DST take advantage of the natural daylight in the summer evenings. That's because the days start to get longer as Earth moves from the winter season to spring and summer, with the longest day of the year on the summer solstice. During the summer season in each hemisphere, Earth, which revolves around its axis at an angle, is tilted directly toward the sun.
Related: Read more about the science of summer.
As Earth orbits the sun, it also spins around its own imaginary axis. Because it revolves around this axis at an angle, different parts of our planet experience the sun's direct rays at different times of the year, leading to the seasons. (Image credit: BlueRingMedia / Shutterstock.com)
Regions farthest away from the equator and closer to the poles get the most benefit from the DST clock change, because there is a more dramatic change in sunlight throughout the seasons.
Research has also suggested that with more daylight in the evenings, there are fewer traffic accidents, as there are fewer cars on the road when it's dark outside. More daylight also could mean more outdoor exercise (or exercise at all) for full-time workers.
The nominal reason for daylight saving time has long been to save energy. The time change was first instituted in the U.S. during World War I, and then reinstituted again during WW II, as a part of the war effort. During the Arab oil embargo, when Arab members of the Organization of Petroleum Exporting Countries (OPEC) stopped selling petroleum to the United States, Congress even enacted a trial period of year-round daylight saving time in an attempt to save energy.
But the evidence for any significant energy savings is slim. Brighter evenings may save on electric lighting, said Stanton Hadley, a now-retired senior researcher at Oak Ridge National Laboratory who helped prepare a report to Congress on extended daylight saving time. But lights have become increasingly efficient, Hadley said, so lighting is responsible for a smaller chunk of total energy consumption than it was a few decades ago. Heating and cooling probably matter more, and some places may need air-conditioning for the longer, hotter evenings of summer daylight saving time.
Hadley and his colleagues found that the four weeks of extra daylight saving time that went into effect in the United States in 2007 did save some energy, about half of a percent of what would have otherwise been used on each of those days, they said in a report to Congress published on Sept. 30, 2020. However, Hadley said, the effect of the entire months-long stretch of daylight saving could very well have the opposite effect.
A 1998 study in Indiana before and after implementation of daylight saving time in some counties found a small increase in residential energy usage. Temporary changes in Australia's daylight saving timing for the summer Olympics of 2000 also failed to save any energy, a 2007 study found.
Part of the trouble with estimating the effect of daylight saving time on energy consumption is that there are so few changes to the policy, making before-and-after comparisons tricky, Hadley told Live Science. The 2007 extension of daylight saving time allowed for a before-and-after comparison of only a few weeks' time. The changes in Indiana and Australia were geographically limited.
Ultimately, Hadley said, the energy question probably isn't the real reason the United States sticks with daylight saving time, anyway.
"In the vast scheme of things, the energy saving is not the big driver," he said. "It's people wanting to take advantage of that light time in the evening."
What places observe daylight saving time?
U.S. daylight saving time
Most of the United States and Canada observe DST on the same dates with a few exceptions. Hawaii and Arizona are the two U.S. states that don't observe daylight saving time, though Navajo Nation, in northeastern Arizona, does follow DST, according to NASA.
Over the years, state legislatures have considered at least 450 bills to establish year-round daylight savings time, according to the National Conference of State Legislatures. And as of 2022, at least 19 states had introduced legislation to make standard time permanent, doing away with DST all together. However, the U.S. Congress would have to amend the Uniform Time Act (15 U.S.C. s. 260a) to authorize states this allowance, according to The New York Times.
Canada daylight saving time
Nine of Canada's 10 provinces observe daylight saving time. The provinces and territories in Canada that stay on standard time all year include: Some regions of the province of British Columbia, parts of Saskatchewan, northwest Ontario and east Quebec, according to timeanddate.com. Meanwhile, Yukon made DST permanent in 2020. The locations in British Columbia that don't use DST include: Chetwynd, Creston, Dawson Creek, Fort Nelson and Fort St. John; in Saskatchewan, only Creighton and Denare Beach observe DST, according to timeanddate.com.
Europe daylight saving time
Most of Europe currently observes daylight saving time, which began at 1 a.m. GMT on the last Sunday in March — that's March 26, 2023, when Europeans move their clocks ahead one hour at 1 a.m. GMT. Daylight saving time ends (winter time) at 1 a.m. GMT on the last Sunday in October, or Oct. 29, 2023, when clocks were moved back an hour. DST will begin again on Sunday, March 31, 2024, according to timeanddate.com.
Most European countries observe DST, with the exception of Russia, Iceland and Belarus, according to timeanddate.com. In the United Kingdom, DST is called British Summer Time (BST).
DST is called Central European Summer Time (CEST) in: Austria, France, Germany, Italy, Hungary, Norway, Poland, Spain and Switzerland. Daylight saving starts at 2 a.m. local time for these countries, when clocks are moved ahead an hour to 3 a.m. The same 2 a.m. clock change is followed for Bulgaria, Estonia, Finland, Greece, Latvia, Lithuania and Romania, which call DST Eastern European Summer Time (EEST).
During summers in Ireland, DST is called Irish Standard Time (IST) and it begins at 1 a.m. local time, when clocks are moved ahead an hour to 2 a.m. The same clock change occurs in the Canary Islands, the Faroe Islands and Portugal, which call DST Western European Summer Time (WEST). However, even the European Union may propose an end to clock changes, as a recent poll found that 84% of 4.6 million people surveyed said they wanted to nix them, the Wall Street Journal reported. If the lawmakers and member states agree, the EU members could decide to keep the EU in summer time or winter time, according to the WSJ.
Southern Hemisphere DST
Australia's states and territories (Image credit: Shutterstock)
The DST-observing countries in the Southern Hemisphere — in Australia, New Zealand, South America and southern Africa — set their clocks forward an hour sometime during September through November and move them back to standard time during the March-April timeframe.
Australia, being such a big country (the sixth-largest in the world), doesn't follow DST uniformly: New South Wales, Victoria, South Australia, Tasmania and the Australian Capital Territory follow daylight saving, while Queensland, the Northern Territory (Western Australia) do not, according to the Australian government. In the observing areas, DST begins on the first Sunday in October — Oct. 1, 2023 — and it ends on the first Sunday in April — or April 2, 2023.
Daylight saving time myths
Turns out, people tend to have more heart attacks on the Monday following the "spring forward" switch to daylight saving time. Researchers reporting in 2014 in the journal Open Heart, found that heart attacks increased 24% on that Monday, compared with the daily average number for the weeks surrounding the start of DST.
Before the Uniform Time Act was passed in the United States, there was a period in which any place could or could not observe DST, leading to chaos. For instance, if one took a 35-mile bus ride from Moundsville, West Virginia, to Steubenville, Ohio, he or she would pass through no fewer than seven time changes, according to Prerau. At some point, Minneapolis and St. Paul were on different clocks.
A study published in 2009 in the Journal of Applied Psychology showed that during the week following the "spring forward" into DST, mine workers got 40 minutes less sleep and had 5.7% more workplace injuries than they did during any other days of the year.
Pets may notice the time change, as well. Since humans set the routines for their fluffy loved ones, dogs and cats living indoors and even cows are disrupted when, say, you bring their food an hour late or come to milk them later than usual, according to Alison Holdhus-Small, a research assistant at CSIRO Livestock Industries, an Australia-based research and development organization.
The fact that the time changes at 2 a.m. at least in the U.S., may have to do with practicality. For instance, it's late enough that most people are home from outings and setting the clock back an hour won't switch the date to "yesterday." In addition, it's early enough not to affect early shift workers and early churchgoers, according to the WebExhibits, an online museum.
Additional resources
Teacher Planet has lots of worksheets and lesson ideas to help kids learn about daylight saving time. The History Channel has a 1-hour video on the history of daylight saving time. In this Smithsonian Magazine feature, you'll learn about a time when the U.S. had year-round DST.


livescience--2020-10-31--Hubble telescope spots a 'Greater Pumpkin' in space for Halloween

As families tuck into their couches to watch Charlie Brown help his friend Linus await the Great Pumpkin this , they may be surprised to hear that NASA has already discovered a `` greater pumpkin . ''
Images from NASA 's show what looks remarkably like a giant jack-o'-lantern in the sky .
The `` pumpkin '' is actually a picture of the early stages of a collision between two galaxies .
The pumpkin 's face consists of two aging red stars , which form the eyes and gives the region an orange-ish glow , and a crooked , blue @ @ @ @ @ @ @ .
With a scattering of blue stars in the foreground , it looks as though the pumpkin dressed up in glitter for Halloween .
Related : These space pumpkins from NASA JPL 's 2019 carving contest are just EPIC !
This `` greater pumpkin '' is , of course , much larger than Charlie Brown 's pumpkin .
The entire view stretches nearly 109,000 light-years across , which is about the diameter of our galaxy , according to NASA .
Although the region currently looks to our eyes like a Halloween pumpkin , @ @ @ @ @ @ @ pair of colliding galaxies become more intertwined .
NASA predicts this pair , which is 120 million light-years away in the constellation Canis Major , might become a giant spiral galaxy .
The `` smile '' may be the beginning of the process to rebuild that spiral , researchers said in a .
The arm of the smile embraces both galaxies and was most likely formed when interstellar gas was compressed as the galaxies started to merge .
Most of the time , when two , they lose their typical flattened disk shape @ @ @ @ @ @ @ scrambled into a new football-shaped space , NASA said .
Eventually , they form an elliptical galaxy .
If the `` greater pumpkin '' becomes a giant spiral galaxy , it will be a rare feat .
There are only a handful of other examples in the universe , including , astronomers said in NASA 's statement .
The mystery and intrigue surrounding what type of galaxy these two colliding galaxies will turn out to be fits its reputation as `` the greater pumpkin . ''
In `` It 's The Great Pumpkin @ @ @ @ @ @ @ never did catch a glimpse of the mysterious great pumpkin he was so excited to see .
Follow Kasandra Brabaw on Twitter @ KassieBrabaw .
Follow us on Twitter @ Spacedotcom and on Facebook .

As families tuck into their couches to watch Charlie Brown help his friend Linus await the Great Pumpkin this Halloween , they may be surprised to hear that NASA has already discovered a "greater pumpkin."
Images from NASA's Hubble Space Telescope show what looks remarkably like a giant jack-o'-lantern in the sky. The "pumpkin" is actually a picture of the early stages of a collision between two galaxies.
The pumpkin's face consists of two aging red stars, which form the eyes and gives the region an orange-ish glow, and a crooked, blue smile made up of newborn star clusters. With a scattering of blue stars in the foreground, it looks as though the pumpkin dressed up in glitter for Halloween.
Related: These space pumpkins from NASA JPL's 2019 carving contest are just EPIC!
Hubble's snapshot of an early-stage collision between two galaxies looks remarkably like a giant jack-o-lantern in the sky. (Image credit: NASA, ESA, and W. Keel (University of Alabama))
This "greater pumpkin" is, of course, much larger than Charlie Brown's pumpkin. The entire view stretches nearly 109,000 light-years across, which is about the diameter of our Milky Way galaxy, according to NASA.
Although the region currently looks to our eyes like a Halloween pumpkin, the shape will soon dissipate as the pair of colliding galaxies become more intertwined. NASA predicts this pair, which is 120 million light-years away in the constellation Canis Major, might become a giant spiral galaxy. The "smile" may be the beginning of the process to rebuild that spiral, researchers said in a NASA image description . The arm of the smile embraces both galaxies and was most likely formed when interstellar gas was compressed as the galaxies started to merge.
Most of the time, when two galaxies collide , they lose their typical flattened disk shape and the stars within each galaxy get scrambled into a new football-shaped space, NASA said. Eventually, they form an elliptical galaxy.
If the "greater pumpkin" becomes a giant spiral galaxy, it will be a rare feat. There are only a handful of other examples in the universe, including Rubin's Galaxy , astronomers said in NASA's statement.
The mystery and intrigue surrounding what type of galaxy these two colliding galaxies will turn out to be fits its reputation as "the greater pumpkin." In "It's The Great Pumpkin, Charlie Brown," poor Linus never did catch a glimpse of the mysterious great pumpkin he was so excited to see.
Follow Kasandra Brabaw on Twitter @KassieBrabaw. Follow us on Twitter @Spacedotcom and on Facebook.


livescience--2020-10-31--Amazing images: The best science photos of the week

Each week at Live Science we find the most interesting and informative articles we can .
Along the way , we uncover some amazing and cool images .
Here you 'll discover the most incredible photos we found this week , and the remarkable stories behind them .
Scientists have captured rare footage of a teeny , tiny squid swimming near the Great Barrier Reef ; the squid is the only living member of its genus and has never before been observed alive and in its natural habitat .
`` Researchers were all surprised to see this squid as it @ @ @ @ @ @ @ seen before , '' Valerie Cornet , a masters student at James Cook University in Australia who is currently conducting research with the Schmidt Ocean Institute , told Live Science in an email .
The ram 's horn squid ( Spirula spirula ) swims with its body in an unusual vertical position with its arms and tentacles pointed up ; at the bottom end of the squid , two ear-shaped fins ripple in the water to keep the animal afloat .
In the footage , the squid can also be seen zooming downward @ @ @ @ @ @ @ vertical .
Schmidt Ocean Institute researchers spotted the squid using a remotely operated vehicle ( ROV ) while mapping the northern off the coast of Cape York in Australia .
While the ROV was cruising at a depth of about 2,760 feet ( 842 meters ) , the team saw a small , cylindrical creature pop up on their video feed .
[ Read more : Elusive squid seen alive in natural habitat for first time ( VIDEO ) ] Ogre-faced spiders hang from their webs , and like gymnasts , they flip @ @ @ @ @ @ @ air .
To hear their prey coming , the spiders `` listen '' for the flap of tiny wings using a special organ in their spindly legs , a new study has found .
The organ looks like a patch of parallel slits cut into the spider 's exoskeleton ; located near the tip of each leg , each slit measures between ( 10-200 nanometers ) in length .
These tiny slits contain nerve cells that detect minute changes in pressure caused by sound waves rippling through the air ; the organ then @ @ @ @ @ @ @ Thus equipped , ogre-faced ( Deinopis spinosa ) can hear sounds up to 6.5 feet ( 2 meters ) away and pick up frequencies between 100 and 10,000 hertz , according to a new study , published Oct. 29 in the journal – all without ears .
( Humans can hear sounds between about 20 and 20,000 hertz , for context . )
[ Read more : Look Ma , no ears !
Teensy spiders hear with organ on their legs ] Scientists suspect that billions `` rogue '' planets – free-floating planets @ @ @ @ @ @ @ exist in the Milky Way , but so far only a handful of candidates have turned up among the 4,000-or-so worlds discovered beyond our .
Most of these potential rogue planets appear to be enormous , measuring thousands of times the size of Earth .
But now , astronomers believe they 've detected a rogue world like no other : a tiny , free-floating planet , roughly the mass of Earth , gallivanting through the gut of the Milky Way .
This discovery , reported today ( Oct. 29 ) in the , @ @ @ @ @ @ @ detected , and it could help prove a long-standing cosmic theory .
According to the study authors , this little world could be the first real evidence that free-floating , Earth-sized planets may be some of the most common objects in the galaxy .
`` The odds of detecting such a low-mass object are extremely low , '' lead study author Przemek Mroz , a postdoctoral scholar at the California Institute of Technology , told Live Science in an email .
`` Either we were very lucky , or such objects are very @ @ @ @ @ @ @ may be as common as stars . ''
[ Read more : An Earth-size planet is careening untethered through the galaxy , scientists find ] Not long after the dinosaurs went extinct , a new breed of giants rose : Monster birds with wingspans that stretched up to 21 feet ( 6.4 meters ) long , about the length of a U-Haul truck .
These enormous birds darkened the skies above as early as 50 million years ago , a new examination of fossils from the continent finds .
The new research reveals @ @ @ @ @ @ @ , called pelagornithids , arose less than 15 million years after an asteroid wiped out the non-avian dinosaurs .
The new study was published Oct. 27 in the journal .
It focused on a bone from a bird 's foot , collected on Seymour Island near the Antarctic Peninsula in the 1980s .
In 2015 , Peter Kloess , a University of California , Berkeley , paleontology graduate student found the bone in the collections of the University of California Museum of Paleontology .
As he looked over the notes accompanying the bone @ @ @ @ @ @ @ from older rock than had originally been recognized .
Instead of being 40 million years old , as it said on the label , the bone was 50 million years old , and far larger than other pelagornithid bones found of that age .
Rapid melt is reshaping coastal , potentially altering the human and animal ecosystems along the country 's coast .
New research published in the on Oct. 27 finds that the ice retreat in Greenland has changed the way glaciers flow and where they dump into the sea .
These @ @ @ @ @ @ @ in the future , the researchers wrote .
Recent studies have shown that Greenland is each year , more than can be replenished by new snowfall .
The new study , led by National Snow and Ice Data Center researchers , breaks down the changes in more detail .
The team combined two types of data from satellite imagery : how fast the ice sheet is moving and where glaciers terminate on their path downhill .
When a glacier retreats , its terminus does n't reach as far downvalley as it once did @ @ @ @ @ @ @ were speeding up , flowing more rapidly toward the sea , the researchers found ; others were flowing more slowly .
And over several years to a decade , a single glacier could do both , depending on the topography around it .
[ Read more : Greenland ice melt is changing the shape of its coastline ] Sue , the mighty whose skeleton is one of the most complete ever found , likely suffered from a big toothache due to three tiny , weird-looking teeth .
`` Two of these teeth are @ @ @ @ @ @ @ lead researcher Kirstin Brink , an assistant professor in the Department of Geological Sciences at the University of Manitoba in Winnipeg , Canada .
`` One of the teeth has some extra serrations on the side of the tooth , not in the normal place on the front or back edges of the tooth . ''
Her research , which is not yet published in a peer-reviewed journal , was presented online Oct. 13 at the Society of Vertebrate Paleontology annual conference , held online this year due to the coronavirus .
Her @ @ @ @ @ @ @ teeth are weirdly misshapen , `` squished and bent with a strange , almost wave-like texture running down the sides , almost as if they were like icing being squeezed through a piping bag , '' Brink said .
This may have been caused by an infection from an oral parasite .
[ Read more : Sue the T. rex had a terribly painful infection when she died ] Eleven months after in the United States , entomologists have tracked down and destroyed the first nest of this invasive , venomous species .
@ @ @ @ @ @ @ ) nest was found on private property in Blaine , Washington , on Friday ( Oct. 23 ) .
On Saturday , state Agriculture Department crews donned protective suits and vacuumed the stinging insects out of the hive , according to the Associated Press .
Next , the tree where the hive was found will be cut down so that crews can search for any baby hornets and determine if any queens may have departed to start new hives in the area .
Asian giant hornets are nicknamed `` murder hornets '' for @ @ @ @ @ @ @ described as feeling like a hot nail driven into flesh .
The hornets can also spray venom from their stingers , which can cause serious eye injuries .
But the real threat from the invasive species is to honeybees ; the giant hornets feed on honeybees , which are already declining in population .
[ Read more : 1st 'murder hornet ' nest in US found and destroyed ] A strange grave found in Scotland holding the medieval remains of what was thought to be a single man surrounded by five skulls — @ @ @ @ @ @ @ is starting to divulge its secrets .
A new analysis now suggests the bones and skulls belong to members of the same extended family .
After the burial was discovered in 1997 near the altar of a former parish church at Portmahomack , a fishing village in the Easter Ross region , archaeologists soon realized two people had been buried in the same grave and surrounded by four disembodied skulls .
The latest research reveals the two men were buried between the late 13th and early 15th centuries , and were cousins or @ @ @ @ @ @ @ of the four skulls came from the same family — the grandfather , father and mother of the second man .
Another relative , probably the son of the second man , was buried nearby .
[ Read more : Who lies in the tomb of the 'Six-Headed Chief ' ?
DNA reveals clues ] What has two brains , no legs and the best profile pic on Facebook ?
That would be this rare , two-headed racer recently discovered by a house cat in Palm Harbor , Florida .
The cat 's @ @ @ @ @ @ @ serpent about a month ago when their cat , Olive , dropped the critter on their living room floor , .
The family was bewildered to see that a small , speckled snake with two heads attached to the same body , each one able to move its eyes , neck and tongue independently .
The family named the snake `` Dos '' — Spanish for `` two . ''
This condition — known as bicephaly — is an uncommon abnormality that occurs during embryonic development , when identical twins fail to fully @ @ @ @ @ @ @ all sorts of animals , and ; humans seem to encounter living bicephalic snakes about once a year .
In 2019 , a bicephalic baby rattlesnake named `` `` turned up in New Jersey , while a slithered onto a family 's property in Virginia in 2018 .
Dos just helped 2020 meet its quota .
An underwater research vessel has stumbled upon a gargantuan , standing like a monolithic tower off the coast of northern Australia .
According to scientists at the Schmidt Ocean Institute , who are conducting a yearlong expedition @ @ @ @ @ @ @ newly discovered reef stands more than 1,640 feet ( 500 meters ) high from base to tip , making it taller than the Empire State Building .
The newly discovered reef is part of the — the single longest coral reef in the world , spanning more than 1,400 miles ( 2,300 km ) along the northeastern coast of Australia .
This new branch of the massive underwater structure stands freely from the rest of the reef , making it the first detached coral reef discovered in the area in 120 years , @ @ @ @ @ @ @ : Coral 'tower ' taller than the Empire State Building discovered off Australian coast ] • Earth from Above : 101 Stunning Images from Orbit • From Big Bang to Present : Snapshots of Our Universe Through Time

Each week at Live Science we find the most interesting and informative articles we can. Along the way, we uncover some amazing and cool images. Here you'll discover the most incredible photos we found this week, and the remarkable stories behind them.
Gargantuan "growlers"
(Image credit: RAF)
In July 2017, a gargantuan iceberg spanning five times the area of New York's five boroughs snapped off the coast of Antarctica and began to drift northward.
Though its edges have crumbled considerably since then, the iceberg — named A-68a — is still the largest on Earth , and it's currently barreling toward an island wildlife refuge in the South Atlantic Ocean. New aerial footage taken by the United Kingdom's Royal Air Force (RAF) reveals just what that island might be up against.
For starters, the RAF footage really drives home how massive this ice giant is. (As of early April, A-68a measured about 2,000 square miles, or 5,100 square kilometers, in area, Live Science previously reported ). The berg's steep walls tower 100 feet (30 meters) above the sea, according to RAF News , and are gouged with tunnels, fissures and caves. Huge chunks of ice, or "growlers," are rapidly cracking off on all sides, leaving behind a trail of debris that could impede boat traffic in the future.
[Read more: World's largest iceberg still barreling toward penguin habitat, new footage confirms ]
Clear head, nine arms, can't lose
(Image credit: Kyodo News via Getty Images)
A nine-armed octopus caught off Japan's coast nearly ended up being dinner, until the family preparing it noticed its extra limb and sent it to a museum instead, according to news sources. While unusual, this extra appendage — which wasn't fully formed, but a small offshoot on a regular arm — isn't unheard of in octopuses, said Michael Vecchione, an invertebrate zoologist at the Smithsonian's National Museum of Natural History in Washington, D.C., who was not involved with this octopus's discovery.
Octopuses are capable of regenerating their arms, but "sometimes regeneration doesn't work quite right," Vecchione told Live Science. "If an arm gets damaged, it might regenerate wrong; it could wind up with extra tissue growing out, and that extra tissue could turn into an arm."
The nine-armed oddity was caught in a trap with three other octopuses on Nov. 13 in Shizugawa Bay, in the northeastern town of Minamisanriku, Japan, according to The Mainichi , a Japanese newspaper.
[Read more: Rare 9-armed octopus found off Japan coast ]
The sound of a supernova
(Image credit: NASA)
In space, nobody can hear you scream — or explode, or collapse, or slowly collide with a neighboring galaxy. But now, thanks to a new " data sonification " program at NASA, you can at least get a sense of what some of the most extreme phenomena in the universe might sound like when converted to sound played by Earthly instruments.
To hear what that sounds like, we turn to NASA's Chandra X-ray center — which has been imaging distant galaxies with its Chandra X-ray observatory for 20 years now. In their new initiative, Chandra researchers have taken three iconic images from their archives and translated different frequencies of light into different pitches of sound.
The first video shows the crab nebula (a supernova remnant powered by a windy neutron star , shown above). In NASA's data sonification of the nebula, X-ray light (blue and white) is represented by brass instruments; optical light (purple) is played by string instruments; and infrared light (pink) is represented by woodwinds. The sounds converge near the center of the nebula, where a rapidly swirling pulsar is blasting gas and radiation in all directions. Listen to this cosmic symphony (and two others) at the link below.
[Read more: This is what a supernova sounds like, according to NASA ]
Pterosaur's missing cousin
(Image credit: Rodolfo Nogueira)
Nearly nothing is known about the family tree of pterosaurs — iconic reptiles that flew alongside the dinosaurs . These now-extinct beasts appear in the fossil record with already developed wings and senses adapted for flying, with researchers having nary a clue about their immediate evolutionary history.
But now, the pterosaur's family tree has a new branch; an enigmatic group of small reptiles, known as lagerpetids, might be the closest-known pterosaur relatives on record, the researchers of a new study say.
Unlike pterosaurs, however, lagerpetids did not fly. "Now, we have an idea of what a flightless pterosaur relative would look like," study co-researcher Sterling Nesbitt, an associate professor of geosciences at Virginia Tech, told Live Science.
[Read more: Missing link in pterosaur origins discovered ]
The changing face of ice
(Image credit: NOAA/Photo courtesy of Caitlin Bailey, GFOE, The Hidden Ocean 2016: Chukchi Borderlands)
From vanishing sea ice to blistering air temperatures to zombie fires , climate change is reshaping the Arctic. And that transformation may be permanent, researchers said on Tuesday (Dec. 8) at the annual meeting of the American Geophysical Union (AGU).
The Arctic has warmed and melted at an alarmingly accelerating pace over the last 15 years, and the impacts are accumulating so rapidly that "there's no reason to think that in 30 years anything will be as it is today," Rick Thoman, an Alaska climate specialist with the International Arctic Research Center (IARC) at the University of Alaska Fairbanks (UAF), said at the conference, held virtually due to the COVID-19 pandemic, on Tuesday.
This year's news was not good: June snow cover across the Eurasian Arctic was at its lowest in 54 years; coastal permafrost erosion is increasing; and glaciers and ice sheets in Greenland continued a trend "of significant ice loss," according to the report.
[Read more: Dramatic transformation of the Arctic landscape may be permanent ]
Starship down
(Image credit: SpaceX)
SpaceX's Starship spaceflight system just took a big step on its path to Mars. The latest Starship prototype, a shiny silver vehicle known as SN8, launched on an epic high-altitude test flight on Dec. 9, taking off at 5:45 p.m. EST from SpaceX's facility near the South Texas village of Boca Chica.
The goal was to soar about 7.8 miles (12.5 kilometers) into the sky, perform some complex aerial maneuvers — including a "belly flop" like the one the final Starship will perform when coming back to Earth on operational flights — and then land safely near the launch stand. The 165-foot-tall (50 meters) SN8 appeared to notch all of these big milestones, except for the final one: The vehicle hit its landing mark but came in too fast, exploding in a dramatic fireball 6 minutes and 42 seconds after liftoff.
SN8's rapid unplanned disassembly did nothing to dampen the spirits of SpaceX founder and CEO Elon Musk, who was thrilled by the results of today's flight.
[Read more: SpaceX's Starship SN8 prototype soars on epic test launch, with explosive landing ]
Amazonian universe
Billions of lasers shot from a helicopter flying over the Brazilian Amazon Rainforest have detected a vast network of long-abandoned circular and rectangular-shaped villages dating from 1300 to 1700, a new study finds.
The round villages all had remarkably similar layouts, with elongated mounds circling a central plaza, like marks on a clock. "These latter elongated mounds, when seen from above, look like the rays of the sun, which gives them the common name of 'Sóis,'" the Portuguese word for "suns," the researchers wrote in the study.
The discovery is part of a new archaeological focus on the pre-Columbian Amazon. Within the past 20 years, researchers have learned that the rainforest's southern rim was home to a great diversity of soil-sculpting cultures that engineered the landscape before the Europeans arrived. Within the past decade, scientists have uncovered the remnants of so-called "mound villages," which are shaped as circles or rectangles, and connected by road networks.
[Read more: Archaeologists find vast network of Amazon villages laid out like the cosmos ]
The sky is falling
(Image credit: ESA)
Have you ever seen 40,000 shooting stars blaze across the sky at the same time?
If you'd like to, the European Space Agency (ESA) is offering you two options: Either stare at the night sky for about half a million years as our solar system drifts steadily through the Milky Way (some patience required) — or, watch a new 60-second time-lapse simulation of the same thing, courtesy of the ESA's Gaia space observatory.
In the new simulation, 40,000 stars — all located within 325 light-years of Earth's sun — whiz through space, leaving long trails of light behind them. Each point of light represents one real object in the Milky Way, and each shining trail shows that object's projected movement through the galaxy over the next 400,000 years. Brighter, faster streaks are located closer to our solar system, while dimmer, slower ones live much farther away.
[Read more: Epic time-lapse shows what the Milky Way will look like 400,000 years from now ]
Gold in the garden
(Image credit: © The Trustees of the British Museum)
A family in England was weeding their garden when they unearthed a valuable treasure — a buried hoard of gold coins dating back to the 1400s, depicting English monarchs from Edward IV to Henry VIII.
The hoard — a stash of 63 gold coins and one silver coin — contains money minted over a period of nearly 100 years, from the late 15th to the 16th centuries. Four of the coins feature Henry VIII and, curiously, one of the initials of three of his wives: Catherine of Aragon, Anne Boleyn and Jane Seymour.
Upon finding the cache, the family, in the New Forest district of Hampshire, a county in southeastern England, notified the British Museum, which runs the Portable Antiquities Scheme (PAS). This program partners with local people who find historical artifacts in the United Kingdom, so the findings can be documented and studied, the British Museum said in a statement Thursday (Dec. 10).
[Read more: Gold coin stash from time of Henry VIII found in English garden ]
Enigma of the deep
(Image credit: Florian Huber/WWF)
Divers trying to remove old fishing nets from the Baltic sea have accidentally stumbled on a Nazi code-making machine. The Enigma machine, as it's called, looks a bit like a typewriter. In fact, the diver who found the device on the ocean floor initially thought that's what the artifact was, according to AFP . But the diving team, on assignment for the conservation group World Wide Fund for Nature (WWF), quickly realized that they had something much stranger.
During World War II, Enigma machines were used to encode German military messages, in hopes of preventing Allied powers from learning about troop movements and other plans. The devices consisted of a keyboard and a series of rotors that did the encoding. The rotors substituted different letters for the ones typed in; different Enigma machines used between three and eight rotors, which moved independently after each keystroke so that the same initial letter typed into the machine would appear as multiple different letters in the final code.
The Enigma machine found by the WWF diving crew was at the bottom of the Bay of Gelting in northeast Germany. It had three rotors, making it the type used on warships, not U-boats. That suggests that the machine may have been tossed overboard in the final days of World War II, in an attempt to keep the technology out of enemy hands, historian Jann Witt of the German Naval Association told the DPA news agency.
[Read more: Nazi 'Enigma' machine found at the bottom of the Baltic Sea ]
Originally published on Live Science.


livescience--2020-10-31--Why did Rome fall?

Why did Rome fall?

When the Roman Empire was at its height , the emperor 's reach stretched from the rain-sodden hills of northern England to the parched deserts of Saudi Arabia .
But when did it start to go wrong ?
Why did Rome fall ?
The answer , it turns out , is not straightforward .
Some argue the sacking of Rome in A.D. 410 by the is as good a marker as any for the end , while others say it was n't until the Middle Ages that the empire 's tenure was finally concluded .
Largely speaking , it depends @ @ @ @ @ @ @ .
In A.D. 395 the Roman Empire was split in two , ever after separately administered as the Western Roman Empire with Rome as its capital and the , Eastern Roman Empire with Constantinople ( modern-day Istanbul ) as its capital , , an online-only history channel .
`` We tend to think of the Byzantines as this separate people and state from the Romans , but they called themselves `` Romanoi '' and saw themselves as citizens of a Roman government , '' said Kristina Sessa , associate professor of history at @ @ @ @ @ @ @ of these two jurisdictions inevitably diverged .
The Western Roman Empire fragmented as various provinces suffered economic and political disrepair within decades of the split .
The Eastern Roman Empire was meanwhile comparatively prosperous for several centuries .
`` You need to distinguish these different regional trajectories , '' Sessa told Live Science .
Related : Deformed 'alien ' skulls offer clues about life during the Roman Empire 's collapse The West crumbled because of a creeping and steady loss of centralized control , sometimes due to incursions by non-Roman tribes and occasionally @ @ @ @ @ @ @ establishment .
It 's hard to mark the precise moment when Rome lost control over a given territory , because unlike the decolonization of imperial empires in the 20th century , it was rare to make or sign documents and declarations of independence .
There were however , landmark battles — between A.D. 460 and A.D. 480m the Visigoths had managed to take substantial parts of what is now France .
But still , the decline of Western Rome was a fairly gradual , nebulous process wherein colonies , one by one , @ @ @ @ @ @ @ of an emperor in Rome .
Instead , autonomous local leaders were increasingly in charge .
`` In some cases , these were Roman usurpers , '' who used coups to take power , said Sessa .
In other cases , these autonomous regions were headed by so-called barbarian regimes .
But the — such as the Franks , Saxons and Vandals — were n't simply raiders from foreign lands chipping away at a weaker Rome .
That 's selling those groups short .
`` That map with all the arrows of invaders @ @ @ @ @ @ @ taking it over , which commonly appears in textbooks , is flat out wrong , '' said Sessa .
Many of the barbarians were coalitions of soldiers that had been working with and for the Roman Empires for several generations .
`` They had been living and working inside the Roman Empire , on behalf of the Roman Empire , for decades if not centuries , '' said Sessa .
That gave the barbarians the opportunity to learn Roman tactics and expertise , which they then applied against the empire , — resulting @ @ @ @ @ @ @ for the Romans .
`` The Roman frontier was n't a border in the modern sense of the nation state .
It was simply a region of diminishing Roman influence where people moved freely around , '' she said .
In that context , it 's easy to see how the frontier could shrink over time .
`` Without a central state , taxes were no longer regularly collected in most areas of the West , which obviously impacted the military , '' explained Sessa .
Dwindling tax revenue made it increasingly tough @ @ @ @ @ @ @ reclaim lands the barbarians had taken .
While the Roman Empire in Western Europe was going to hell in a handbasket , the Eastern Romans carried on .
`` The East , by comparison , remained consolidated and focused around the city of Constantinople , '' said Sessa .
Its demise , however , was very much at the hands of an outside invading force .
`` It was over the course of the seventh and eighth centuries that the Eastern Empire began to undergo a similar political fragmentation , though in this @ @ @ @ @ @ @ and regimes ; the Persians , the Slavs and the Arabs , '' she added .
It was n't until 1453 , when the Ottomans sacked Constantinople , that we can truly say the Roman Empire ended .

When the Roman Empire was at its height, the emperor's reach stretched from the rain-sodden hills of northern England to the parched deserts of Saudi Arabia. But when did it start to go wrong? Why did Rome fall?
The answer, it turns out, is not straightforward. Some argue the sacking of Rome in A.D. 410 by the Visigoths is as good a marker as any for the end, while others say it wasn't until the Middle Ages that the empire's tenure was finally concluded. Largely speaking, it depends on which ancient Rome we're talking about. In A.D. 395 the Roman Empire was split in two, ever after separately administered as the Western Roman Empire with Rome as its capital and the Byzantine , Eastern Roman Empire with Constantinople (modern-day Istanbul) as its capital, according to HistoryHit , an online-only history channel.
"We tend to think of the Byzantines as this separate people and state from the Romans, but they called themselves "Romanoi" and saw themselves as citizens of a Roman government," said Kristina Sessa, associate professor of history at The Ohio State University.
The fates of these two jurisdictions inevitably diverged. The Western Roman Empire fragmented as various provinces suffered economic and political disrepair within decades of the split. The Eastern Roman Empire was meanwhile comparatively prosperous for several centuries. "You need to distinguish these different regional trajectories," Sessa told Live Science.
Related: Deformed 'alien' skulls offer clues about life during the Roman Empire's collapse
The West crumbled because of a creeping and steady loss of centralized control, sometimes due to incursions by non-Roman tribes and occasionally instigated by traitors from within the Roman establishment. It's hard to mark the precise moment when Rome lost control over a given territory, because unlike the decolonization of imperial empires in the 20th century, it was rare to make or sign documents and declarations of independence. There were however, landmark battles — between A.D. 460 and A.D. 480, the Visigoths had managed to take substantial parts of what is now France . But still, the decline of Western Rome was a fairly gradual, nebulous process wherein colonies, one by one, were no longer realistically under the sway of an emperor in Rome. Instead, autonomous local leaders were increasingly in charge.
At its peak, the Roman empire stretched across continents, but it eventually fragmented and gave way to rival powers. (Image credit: Shutterstock)
"In some cases, these were Roman usurpers," who used coups to take power, said Sessa. In other cases, these autonomous regions were headed by so-called barbarian regimes. But the barbarians — such as the Franks, Saxons and Vandals — weren't simply raiders from foreign lands chipping away at a weaker Rome. That's selling those groups short. "That map with all the arrows of invaders coming into the empire from beyond and taking it over, which commonly appears in textbooks, is flat out wrong," said Sessa. Many of the barbarians were coalitions of soldiers that had been working with and for the Roman Empires for several generations.
"They had been living and working inside the Roman Empire, on behalf of the Roman Empire, for decades if not centuries," said Sessa. That gave the barbarians the opportunity to learn Roman tactics and expertise, which they then applied against the empire, resulting in a series of withering military defeats for the Romans. "The Roman frontier wasn't a border in the modern sense of the nation state. It was simply a region of diminishing Roman influence where people moved freely around," she said.
In that context, it's easy to see how the frontier could shrink over time. "Without a central state, taxes were no longer regularly collected in most areas of the West, which obviously impacted the military," explained Sessa. Dwindling tax revenue made it increasingly tough for Rome to muster enough legions to reclaim lands the barbarians had taken.
While the Roman Empire in Western Europe was going to hell in a handbasket, the Eastern Romans carried on. "The East, by comparison, remained consolidated and focused around the city of Constantinople," said Sessa.
Its demise, however, was very much at the hands of an outside invading force.
"It was over the course of the seventh and eighth centuries that the Eastern Empire began to undergo a similar political fragmentation, though in this case we are talking about external armies and regimes; the Persians, the Slavs and the Arabs," she added. It wasn't until 1453, when the Ottomans sacked Constantinople, that we can truly say the Roman Empire ended.
Originally published on Live Science.


livescience--2020-10-31--How to watch rare Halloween 'blue moon' tonight

If anyone is trying to wake some dark spirits , tonight 's the night .
is here ( Oct. 31 ) , along with a full `` blue moon '' — meaning the second full moon in a single month .
All Hallow 's Eve full moons are rare enough , occurring about once every 19 years .
But this is the first time since 1944 that trick-or-treating has lined up with a blue moon , according to the .
The spooky lightshow in the sky should begin soon enough for even the earliest candy-hunters .
Moonrise should happen between @ @ @ @ @ @ @ most of the United States , with some variance between different latitudes and positions within time zones .
Right after moonrise , the moon should be visible at the horizon .
As the night wears on , it will rise higher and shine brighter — illuminating any tricksters out egging houses ( no , do n't do that ! )
.
Much of the U.S. should have clear enough night skies to spot the blue moon while out trick-or-treating , though clouds are in the forecast for New Jersey , New York and @ @ @ @ @ @ @ as the Pacific Northwest and central Minnesota , according to the .
The first full moon this October , which rose on the first of the month , also had a special name : the `` Harvest Moon , '' referring to the first full after the September equinox .
( The second full moon of autumn , this blue moon , sometimes takes the name `` Beaver Moon , '' according to . )
The blue moon ( or Beaver Moon ) occurs thanks to a routine coincidence of the Gregorian calendar @ @ @ @ @ @ @ It 's a term that seems to have originated in the 1940s , according to Sky and Telescope .
There are some special things going on with the moon right now though .
For one thing , it 's at the farthest point in its orbit from Earth , about 31,000 miles ( 50,000 kilometers ) more distant than its 239,000 mile ( 385,000 km ) average .
That makes this full blue moon also a `` Micro Moon , '' though it should look just barely smaller than a `` Super Moon @ @ @ @ @ @ @ closest to Earth in its orbit ) .
More spectacularly , NASA researchers confirmed this month the presence of expansive deposits of frozen water on the moon .
Some of it is sandwiched between grains of moon dust .
But more of it may exist as vast frozen lakes , hidden in the darkest parts of deep craters , .
And just a few months ago , researchers showed that tunnels likely exist under the lunar surface , big enough to house whole cities .
One final thing to look for in the @ @ @ @ @ @ @ The Red Planet is at its closest to right now , even as humans reach out ever more intently with and plans for human missions toward its surface .
Right now , no human being has ever been up there .
But some Halloween sooner or later , there might be visitors playing dress-up on ( or under ) the Martian crust .

More of the rust was found on the near-side of the moon. The near-side of the moon is captured here by NASA's robotic Lunar Reconnaissance Orbiter spacecraft.
If anyone is trying to wake some dark spirits, tonight's the night.
Halloween is here (Oct. 31), along with a full "blue moon" — meaning the second full moon in a single month. All Hallow's Eve full moons are rare enough, occurring about once every 19 years. But this is the first time since 1944 that trick-or-treating has lined up with a blue moon, according to the Farmer's Almanac .
The spooky lightshow in the sky should begin soon enough for even the earliest candy-hunters. Moonrise should happen between 5:50 and 6:40 p.m. local time across most of the United States, with some variance between different latitudes and positions within time zones. Right after moonrise, the moon should be visible at the horizon. As the night wears on, it will rise higher and shine brighter — illuminating any tricksters out egging houses (no, don't do that!).
Related: Gallery: The fantastic full moon
Much of the U.S. should have clear enough night skies to spot the blue moon while out trick-or-treating, though clouds are in the forecast for New Jersey, New York and part of New England, as well as the Pacific Northwest and central Minnesota, according to the National Weather Service .
The first full moon this October, which rose on the first of the month, also had a special name: the "Harvest Moon," referring to the first full moon after the September equinox. (The second full moon of autumn, this blue moon, sometimes takes the name "Beaver Moon," according to NASA .)
The blue moon (or Beaver Moon) occurs thanks to a routine coincidence of the Gregorian calendar months and the regular moon phases. It's a term that seems to have originated in the 1940s, according to Sky and Telescope .
The full moon on Oct. 31 is the second full moon during October 2020. (Image credit: NASA/JPL-Caltech)
There are some special things going on with the moon right now though.
For one thing, it's at the farthest point in its orbit from Earth, about 31,000 miles (50,000 kilometers) more distant than its 239,000 mile (385,000 km) average. That makes this full blue moon also a "Micro Moon," though it should look just barely smaller than a "Super Moon" (that's Luna at its closest to Earth in its orbit).
More spectacularly, NASA researchers confirmed this month the presence of expansive deposits of frozen water on the moon. Some of it is sandwiched between grains of moon dust. But more of it may exist as vast frozen lakes, hidden in the darkest parts of deep craters, as Chelsea Gohd reported for Live Science sister site Space.com . And just a few months ago, researchers showed that tunnels likely exist under the lunar surface , big enough to house whole cities.
One final thing to look for in the sky Halloween night sky: Mars. The Red Planet is at its closest to Earth right now, even as humans reach out ever more intently with probes and plans for human missions toward its surface. Right now, no human being has ever been up there. But some Halloween sooner or later, there might be visitors playing dress-up on (or under) the Martian crust.
Originally published on Live Science.


livescience--2020-11-01--Are you genetically more similar to your mom or your dad?

`` He 's the spitting image of his dad ! ''
Or : `` She 's her mom 's clone — except for the nose .
Clearly from her father 's side of the family . ''
As we watch kids grow up , we tend to look for likenesses between them and their parents .
So which parent contributes more genetically ?
The answer depends on whether you 're asking about the total number of genes a kid inherits from mom and dad , or which parents ' genes are actually doing more .
But either way , scientists @ @ @ @ @ @ @ 50/50 .
For example , most people know that genes are carried on strands of that are packaged into 23 X- or Y-shaped .
Those autosomes are housed inside a cell 's nucleus , and the DNA they contain comes equally from both of our parents .
But the cell actually contains one other chromosome — hiding inside the .
The mitochondria , or the `` powerhouse '' of the cell , produces a cell 's energy and plays an important role in exercise and aging , according to a 2011 review published @ @ @ @ @ @ @ has its own set of DNA — and we inherit it only from our mom .
`` That 's a clear example that you 're more similar to your mum than your dad , '' said Marika Charalambous , a geneticist at King 's College London .
Some studies suggest that our mitochondrial DNA — and therefore our mom — plays a key role in our athletic endurance .
For example , Spanish and Israeli scientists looked at one mitochondrial gene , which is associated with the amount of oxygen cells we can @ @ @ @ @ @ @ which was published in 2005 in the , found that a variant of the gene associated with lower fitness was less frequent in elite cyclists and runners than in the general population , a result confirmed by later studies .
A series of studies brought home the importance of moms in the inheritance of this and other genes .
They found that a mother 's capacity for exercise alone can better predict a child 's capacity , than when fathers are taken into account .
But instead of asking which parent contributes more @ @ @ @ @ @ @ 's genes do more .
Most of the surface-level differences we see between people are not due to the genes themselves , but to a series of chemical `` switches '' that sit on top of our DNA and tell our body which portions to read and translate into protein and which to ignore , Charambalous told Live Science .
`` There 's a whole level of genetic variation between people that 's not just the sequences of the genes , '' Charambalous said .
In a phenomenon called imprinting , these switches @ @ @ @ @ @ @ only when they come from a particular parent .
These patterns persist across generations .
For example , if gene ' A ' is paternally imprinted , it will always work if it comes from your mom , but never if it comes from your dad .
Most studies suggest there are between 100 and 200 imprinted genes in the body , but some research suggests there could be more , according to a 2012 article published in the journal .
These genes are particularly important in the brain and the placenta .
@ @ @ @ @ @ @ imprinting biases gene expression toward one parent or another .
Evidence suggests that there are similar numbers of maternal and paternal imprinted genes , said Andrew Ward , a geneticist at the University of Bath in England .
`` In the traits which imprinting genes are responsible for , in a sense you are likely to be more like one parent than another , '' Ward told Live Science .
In other words , imprinting may have an affect on certain traits — from our body size to sleep and memory .
But @ @ @ @ @ @ @ and those genes are likely balanced between parents , imprinting is n't going to determine whether you have a striking likeness to mom versus dad , Ward said .
But studies in mice do suggest that there might be some imbalance favoring fathers in this regard .
A 2015 study published in the journal found that imprinted genes were 1.5 times more likely to be silent on the mom 's side and active on the dad 's side.An earlier study published in 2008 in the journal found a similar result .
In the @ @ @ @ @ @ @ were active when they came from the father .
The opposite was true in the placenta .
However , there 's no evidence , at least not yet , that such an imbalance happens in humans .
But even if imprinted genes bias gene expression from one parent over the other , it would n't necessarily make you more similar to that parent .
After all , the gene that 's active in you might be silent in them , said Edward Chuong , a genome biologist at the University of Colorado Boulder @ @ @ @ @ @ @ your gene expression ] is thanks to your parents , '' Chuong told Live Science , `` But it 's complicated to say it 's similar to your parents . ''

"He's the spitting image of his dad!" Or: "She's her mom's clone — except for the nose. Clearly from her father's side of the family." As we watch kids grow up, we tend to look for likenesses between them and their parents. So which parent contributes more genetically?
The answer depends on whether you're asking about the total number of genes a kid inherits from mom and dad, or which parents' genes are actually doing more. But either way, scientists think that the answer isn't exactly 50/50.
For example, most people know that genes are carried on strands of DNA that are packaged into 23 X- or Y-shaped chromosomes . Those autosomes are housed inside a cell's nucleus, and the DNA they contain comes equally from both of our parents. But the cell actually contains one other chromosome — hiding inside the mitochondria . The mitochondria, or the "powerhouse" of the cell, produces a cell's energy and plays an important role in exercise and aging, according to a 2011 review published in the journal Physiological Genomes . The mitochondria also has its own set of DNA — and we inherit it only from our mom.
Related: Unraveling the human genome: 6 molecular milestones
"That's a clear example that you're more similar to your mum than your dad," said Marika Charalambous, a geneticist at King's College London.
Some studies suggest that our mitochondrial DNA — and therefore our mom — plays a key role in our athletic endurance. For example, Spanish and Israeli scientists looked at one mitochondrial gene, which is associated with the amount of oxygen cells we can use during exercise. Their study, which was published in 2005 in the Journal of Applied Physiology , found that a variant of the gene associated with lower fitness was less frequent in elite cyclists and runners than in the general population, a result confirmed by later studies. A series of studies brought home the importance of moms in the inheritance of this and other genes. They found that a mother's capacity for exercise alone can better predict a child's capacity, than when fathers are taken into account.
But instead of asking which parent contributes more genes, you might ask which parent's genes do more. Most of the surface-level differences we see between people are not due to the genes themselves, but to a series of chemical "switches" that sit on top of our DNA and tell our body which portions to read and translate into protein and which to ignore, Charambalous told Live Science. "There's a whole level of genetic variation between people that's not just the sequences of the genes," Charambalous said.
In a phenomenon called imprinting, these switches entirely shut off certain genes — but only when they come from a particular parent. These patterns persist across generations. For example, if gene 'A' is paternally imprinted, it will always work if it comes from your mom, but never if it comes from your dad. Most studies suggest there are between 100 and 200 imprinted genes in the body, but some research suggests there could be more, according to a 2012 article published in the journal PLOS Genetics . These genes are particularly important in the brain and the placenta.
There's some disagreement as to whether imprinting biases gene expression toward one parent or another. Evidence suggests that there are similar numbers of maternal and paternal imprinted genes, said Andrew Ward, a geneticist at the University of Bath in England. "In the traits which imprinting genes are responsible for, in a sense you are likely to be more like one parent than another," Ward told Live Science. In other words, imprinting may have an affect on certain traits — from our body size to sleep and memory. But because imprinting happens on relatively few genes and those genes are likely balanced between parents, imprinting isn't going to determine whether you have a striking likeness to mom versus dad, Ward said.
But studies in mice do suggest that there might be some imbalance favoring fathers in this regard. A 2015 study published in the journal Nature Genetics found that imprinted genes were 1.5 times more likely to be silent on the mom's side and active on the dad's side. An earlier study published in 2008 in the journal PLOS ONE found a similar result. In the brain, the majority of imprinted genes were active when they came from the father. The opposite was true in the placenta. However, there's no evidence, at least not yet, that such an imbalance happens in humans.
But even if imprinted genes bias gene expression from one parent over the other, it wouldn't necessarily make you more similar to that parent. After all, the gene that's active in you might be silent in them, said Edward Chuong, a genome biologist at the University of Colorado Boulder.
"You can say it [your gene expression] is thanks to your parents," Chuong told Live Science, "But it's complicated to say it's similar to your parents."
Originally published on Live Science.