00:00Hey, look at this blazing monster. It's a white dwarf
00:03These stars are known for gobbling up passing objects and one day these objects might be the planets of our own solar system
00:11According to a new study parts of the solar system will be pulled into a white dwarf star
00:16Crushed up and eventually ground into a fine dust like coffee beans and a blade grinder. Hey, you like that analogy?
00:24Now white dwarfs are a final stage of a star's life
00:27It's a small but very dense star
00:29that's typically the size of a planet the result of a low-mass star exhausting all the nuclear fuel in its center and
00:37Losing its outer layers as a planetary nebula
00:41When our Sun turns into a white dwarf and it is bound to happen sometime
00:46It'll destroy the asteroids and moons around Mars and Jupiter. They will be pulverized by its gravity
00:52Earth though will be swallowed up even before the Sun turns into a white dwarf, but it won't happen for another six billion years
01:01Researchers working on this topic have come to such conclusions by observing what happened to space bodies
01:07Asteroids moons and planets that were passing close to three white dwarfs for 17 years
01:12They observed and analyzed transits
01:15That's when the brightness of a white dwarf dips because of an object in a stable orbit passing in front of it
01:21in the case of white dwarfs
01:23We can predict such transits and use them to study the stars themselves and celestial objects passing by them
01:31So when something gets too close to a white dwarf star the star's immense gravity
01:36Rips it into smaller and smaller pieces of debris
01:40The team also found out that transits of such debris are chaotic
01:44Plus this debris is oddly shaped which means that it is being devoured further
01:50The first white dwarf used for studying the transit process this here guy
01:55Seems steady and well-behaved over the last few years
01:58Well until scientists found some evidence of a massive catastrophic event that occurred in 2010 or so
02:04The next star dims irregularly every couple of months before brightening again
02:09And the third dwarf star used to behave close to theoretical predictions
02:14It had transits that varied in number shapes and depths
02:17But the latest study has shown that the transits are now completely gone and this indicates the
02:24Unpredicted nature of transits one minute you see them the next poof
02:28the reason might be the chaotic environment they have to exist in as
02:32For our own solar system and our planet in general its fate looks pretty sad
02:38Earth will be swallowed by the expanding Sun even before our star turns into a white dwarf
02:44As for the rest of the solar system
02:46Located further from the Sun some of the asteroids between Mars and Jupiter as well as some of Jupiter's moons will be destroyed later
02:53Oh, well, they're likely to get dislodged and travel too close to the white dwarf
03:01Now at the same time astronomers aren't 100% sure that it's exactly what will happen with our solar system
03:08So I guess we'll just have to wait and see for like six billion years
03:13Speaking of white dwarfs
03:15Scientists have recently found one that has a bizarre metallic scar on its surface
03:19This blemish could have formed after the star ripped up and ate a tiny planet orbiting it
03:25White dwarfs with traces of metal in their atmospheres aren't rare. These traces are left by planets falling into stars affected by their gravity
03:34Experts have long thought that such metal should be distributed evenly across the surface of such polluted white dwarfs
03:41But a new study had discovered a white dwarf with a weird concentrated patch of metal
03:46The star was monitored over a period of two months with the help of the Very Large Telescope in Chile
03:52The researchers found an opaque patch of metal
03:55It was located over one of the stars magnetic poles and blocked some of the stars light as it rotated
04:01based on this position
04:03Astronomers concluded that the material could have been funneled into the star by its powerful magnetic field
04:09This process is similar to one causing auroras on earth where charged particles follow the magnetic field to the surface
04:18Now the planet destroyed by the white dwarf was most likely very small around the same size as
04:24asteroid Vesta in our solar system, which is a mere
04:28326 miles across its debris is now prominently displayed on the host star surface
04:34It makes it easier for researchers to examine what the planet's geochemistry was before it was devoured
04:40Such a study might even turn out to be one of the best ways to observe small worlds beyond the solar system
04:46Even if such a world has already met its demise
04:49There might be many more scarred stars like this one. The one in question was the first but probably not the last
04:57Even better astronomers have already discovered two white dwarfs that seem to have similar scars
05:03Making repeat observations of such stars might help us unearth pardon the pun
05:08No, I meant to do that unearth even more secrets and make more discoveries
05:13Another bizarre white dwarf discovered not long ago seems to have stopped cooling due to the formation of internal crystals
05:20It challenges existing theories on star aging and also questions the method of stellar age estimation
05:27But scientists might have understood why it may be happening
05:33White dwarfs are believed to be dead stars to keep cooling down over time and normally this process can't be reversed or paused
05:41But in 2019 the European Space Agency's Gaia
05:45Satellite discovered a number of white dwarf stars that had stopped cooling for more than 8 billion years
05:51It might mean that some white dwarfs can generate a lot of extra energy
05:55Which is at odds with the classical dead star theory at first astronomers couldn't figure out how it might happen
06:02But in the end more than 97% of stars in the Milky Way galaxy turn into white dwarfs
06:09Astronomers have long thought that such stars are at the end of their lives after depleting their nuclear energy source
06:15They stop producing heat and cool down
06:18Eventually the dense plasma in their insides freezes into a solid state and the star solidifies from inside out
06:25The whole process can take billions of years
06:29But the new research claims that in some white dwarfs this dense plasma doesn't simply freeze
06:36Instead it's solid crystals forming upon freezing become less dense than the liquid and start floating around
06:43They displace the heavier liquid downward the movement of heavier material toward the center of a white dwarf
06:50Releases gravitational energy and this energy is enough to interrupt the stars cooling process and halt it for billions of years
06:57Now this explanation actually matches all of the properties of the unusual white dwarf population
07:03But this is the first time such a transport mechanism has been seen in any type of star and that's incredibly exciting
07:11a totally new
07:13Astrophysical phenomenon, but why does it happen in some stars?
07:16But not in others it most likely depends on the composition of the star
07:21You see some white dwarf stars are formed by the merger of two different stars
07:25When they collide and form a white dwarf it changes the composition of the star which allows the formation of floating crystals
07:35So this discovery might mean that astronomers will have to review the ways they use to determine the age of stars at the moment
07:42White dwarfs are often used as age indicators. The cooler a white dwarf is the older it's believed to be
07:49But now we already know about possible delays in the cooling process of some dwarfs
07:55It makes the popular age determination method more unreliable
07:59Some stars of a given temperature may be billions of years older than we previously thought
08:05The recently uncovered transport mechanism within white dwarfs means that some of these stars can be shining as bright as normal
08:12for billions of years
08:14This complicates age dating and the use of white dwarfs to reconstruct the formation of our galaxy. Hey stay tuned
08:24That's it for today
08:25So hey
08:26If you pacified your curiosity then give the video a like and share it with your friends
08:31Or if you want more just click on these videos and stay on the bright side
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