Beneath East Antarctica’s thick ice lies the Wilkes Land anomaly — a possible meteorite impact crater over 500 km wide. This mysterious formation may be the largest crater on Earth, with a mascon at its center and a history tied to ancient tectonic shifts. Explore the science behind this giant crater under Antarctica and what it could reveal about Earth’s violent past. Animation is created by Bright Side. ---------------------------------------------------------------------------------------- Music from TheSoul Sound: https://thesoul-sound.com/
Check our Bright Side podcast on Spotify and leave a positive review! https://open.spotify.com/show/0hUkPxD34jRLrMrJux4VxV Subscribe to Bright Side: https://goo.gl/rQTJZz ---------------------------------------------------------------------------------------- Our Social Media: Facebook: https://www.facebook.com/brightplanet/ Instagram: https://www.instagram.com/brightside.official TikTok: https://www.tiktok.com/@brightside.official?lang=en
Stock materials (photos, footages and other): https://www.depositphotos.com https://www.shutterstock.com https://www.eastnews.ru ---------------------------------------------------------------------------------------- For more videos and articles visit: http://www.brightside.me ---------------------------------------------------------------------------------------- This video is made for entertainment purposes. We do not make any warranties about the completeness, safety and reliability. Any action you take upon the information in this video is strictly at your own risk, and we will not be liable for any damages or losses. It is the viewer's responsibility to use judgement, care and precaution if you plan to replicate.
00:00A long, long time ago, a huge meteorite smashed into the Earth with a horrible destructive
00:06power.
00:07It was several times bigger than the one that wiped out the dinosaurs 65 million years ago.
00:13Luckily, there were no lives it could have taken, or else it would have been a real catastrophe.
00:19Now, scientists think it did leave behind a huge footprint, the massive Antarctica impact
00:25crater that is bigger than the entire state of New York.
00:29The location also has a gravitational Wilkes Land anomaly going on.
00:34At first, scientists noticed something weird here when they measured Earth's gravity in
00:39that region.
00:40A strange gravity hole, or a negative gravity anomaly.
00:45Later, with better technology, they found something even weirder.
00:49There was a positive gravity anomaly inside that gravity hole, a spot with stronger gravity.
00:57This kind of structure, called a mascon, short for mass concentration, often shows up in
01:02places where giant space rocks or meteorites have slammed into the planet.
01:07When a meteor hits hard enough, it punches through the Earth's crust and shakes the mantle below.
01:12It can spring back up and leave behind a super dense plug of material, which causes
01:18stronger gravity right in the center of the crater.
01:21It's something like a frosty donut, with ice filling the gap and a dense center rising up from underneath.
01:28In 2018, scientists used advanced scanning techniques to study and map the Wilkes Land meteorite impact in more detail than ever before.
01:38They saw that it wasn't a perfect circle, but more of a U-shape, and the northern part looked like something had broken it apart.
01:46It possibly happened when Australia split away from Antarctica about 35 million years ago.
01:53Some scientists even think you can still see parts of the crater in southern Australia today.
01:58This clue also supports the idea that the giant crater under Antarctica formed before the continents broke apart.
02:07There have been different ideas about what created this strange formation.
02:12Some said it might be a volcano, or an eroded valley, or even a sedimentary basin.
02:18That is a place where sediments build up over millions of years.
02:22But many scientists now believe the most likely explanation is a massive meteor impact.
02:29It was possibly one of the biggest to ever hit Earth.
02:32A 2015 study even estimated the age of the crater as its size matches the kind of space rocks that smashed into Earth between 4.1 and 3.8 billion years ago.
02:45The Wilkes Land meteorite impact was so powerful because the meteor that caused it could have been up to 30 miles wide.
02:52That's four to five times wider than the Chicxulub meteor that wiped out the dinosaurs 66 million years ago.
02:59Even that meteor was enough to cause massive destruction with wildfires, acid rain, tsunamis, and a climate crash that wiped out about 75% of all existing life.
03:12So it was lucky in a way that the meteorite that gave us the giant crater under Antarctica visited at a time when there were only microbes and no plants or animals on Earth.
03:23It didn't cause mass extinction or leave behind charcoal from ancient fires, but it may have changed the entire planet.
03:32Still, scientists haven't put the Wilkes Land Anomaly mystery in the solved files because the crater is buried deep under Antarctica's thick ice sheet.
03:41It's hard to study up close.
03:44Scientists say we can't rule out the other ideas just yet, but if the meteor theory is right, then the Wilkes Land Crater could be the largest known impact crater on Earth.
03:55So far, this title belongs to another contestant, the Vredefort Crater in South Africa.
04:02Right now, the crater is around 99 miles wide, which is huge, but it's not as wide as the Chicxulub Crater in Mexico, which is about 112 miles wide.
04:15But the Vredefort Crater used to be way bigger, around 155 to 174 miles wide, before time and erosion wore it down.
04:26That means, even though the Chicxulub impact was striking, the Vredefort impact was likely even more powerful, the biggest one we know of that hit Earth.
04:37According to the latest study, that asteroid was 12.4 to 15.5 miles wide and might have hit Earth at a speed of 45,000 to 56,000 miles per hour.
04:49It's important for science because knowing the real size of this impact helps us build better models to understand Earth's geology and how giant impacts shape planets even beyond Earth.
05:04Measuring ancient craters is really tricky.
05:07Over two billion years, erosion wears away the edges, and newer rocks form over the crater.
05:13That's what happened to Vredefort.
05:15Now, only small bits of the original crater rim are visible, and the rest is hidden under newer rock.
05:22To figure out its true size, scientists studied minerals like quartz and zircon found around the crater.
05:29These minerals still have fractures and shock patterns that show us how powerful the blast was.
05:36Wilkes land anomaly isn't the only case on our planet where gravity is acting weirdly.
05:42For over 40 years, scientists were trying to solve a strange mystery in Canada.
05:47Parts of the country, especially around Hudson Bay, seem to have less gravity than the rest of the world.
05:54That means if you stepped on a scale there, you'd weigh just a tiny bit less than usual.
06:00Researchers first discovered this weird difference in the 1960s when they were mapping Earth's gravity.
06:07Gravity is linked to mass.
06:09The more mass there is, the stronger the gravity.
06:12And since Earth isn't shaped perfectly like a ball but is slightly squashed at the poles and bulges at the equator,
06:19it makes sense that its mass isn't spread out evenly.
06:23So, the first out of the two main theories to explain the Hudson Bay mystery has to do with magma.
06:30Yes, that super-hot, gooey rock deep under our planet's surface.
06:35Magma constantly churns, like boiling soup, in a process called convection.
06:41As this magma moves, it can drag parts of Earth's crust down with it.
06:45That makes the area lighter, which lowers the gravity.
06:50The second area has to do with the Laurentide Ice Sheet,
06:54a massive glacier that covered much of Canada during the last ice age.
06:58This ice was up to 2.3 miles thick in some parts of Hudson's Bay.
07:02That's like stacking 10 Empire State Buildings on top of each other.
07:07Because it was so heavy, the ice pressed the land down like a thumb on a sponge.
07:13Even though the ice melted away about 10,000 years ago,
07:17the land underneath is still slowly bouncing back, kind of like a memory foam mattress after you get up.
07:24This slow rise is called glacial rebound and it's happening at less than half an inch per year.
07:31Until the land fully bounces back, which could take 5,000 more years,
07:36it will continue to have less mass, and that means less gravity.
07:42Both of these theories are right.
07:44To figure this out, scientists used super-advanced satellites,
07:48which floated around 300 miles above Earth for several years.
07:52These satellites flew in pairs and detected how far apart they were pulled
07:57as they passed over areas like Hudson Bay, to measure tiny changes in gravity.
08:03When the front satellite passed over a low-gravity area, it drifted just slightly,
08:08and that change was recorded.
08:10Thanks to this research, scientists created detailed maps
08:14showing what Hudson Bay looked like during the last ice age.
08:18They discovered two huge bulges on the west and east sides, where the ice was thickest.
08:23And those spots have the weakest gravity today.
08:26The effects of this are still visible, and while sea levels are rising in most parts of the world,
08:32the land around Hudson Bay is rising so fast that sea levels there are actually dropping.
08:39Solving mysteries like this, or the Antarctica Impact Crater anomaly,
08:43gives scientists amazing insights into the past of our planet.
08:46And by understanding how past changes in temperature and geology affected Earth,
08:53scientists can predict how today's human activity can impact our future.
09:01That's it for today. So, hey, if you pacified your curiosity,
09:04then give the video a like and share it with your friends.
09:07Or, if you want more, just click on these videos and stay on the Bright Side!
