Why White Dwarf Stars Unexpectedly Stop Cooling Down

White dwarf stars should be cooling down practically till the end of the Universe. But yet, they don't. They stop cooling at some point. Why does this happen? Figuring out the answers with Dr Simon Blouin from the University of Victoria.
👉 Dr Simon Blouin
www.sblouin.com/
📜 Buoyant crystals halt the cooling of white dwarf stars
www.nature.com/articles/s4158...
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00:00 Intro
01:16 What are White Dwarfs
08:59 Why white dwarfs stop cooling
23:03 Pollution of white dwarfs
29:29 Perfect white dwarf telescope
35:59 Current obsessions
38:25 Final thoughts and more interviews
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[@sjzara]

You are the best questioner. You get such fascinating answers, politely pressing until you get there. White dwarfs turning into solid plasmas is amazing.

[@zippythinginvention]

Amazing. Fantastic. Debatable...

[@KOZMOuvBORG]

Wouldn't solid plasma be similar to metal - ions in a sea of electrons?

[@Overfloable]

I loved the topic, thank you. This is in the category: "didn't realise I always wanted to know more about this". Awesome! You can definitely tell how full of enthusiasm Simon is with how he's looking for the right answer and filtering tangents. Great video as always

[@marzchart591]

Une chance que j'ai jamais rencontré ce gars là dans un bar on serait encore en train de jaser de solid plasma.

[@dougieh9676]

Jajaja, eres gracioso. 😂

[@sspoonless]

Now t h a t was a great interview. I learned more from him than any I can remember. Dead star forensics, dead planet forensics, nova alchemy, ...

[@frasercain]

Fantastic

[@longboardfella5306]

Hi @frasercain - so this seems to me like the energy of the crystallization is being used to maintain a constant temperature - much like the freezing of eutectic crystals used to maintain a constant temperature in some passively cooled / heated houses. And this remains the case until the liquid phase is all turned to crystal. But in this case, the convection of the crystals keeps this process efficient for a very long time due to the efficient mixing. Am I on the right track in my understanding? It was a fascinating interview - keep going with the deep dives of the interviews. They are great.

[@mikefeierberg7712]

What an excellent interview! I felt the excitement that a young astronomer feels when they find something that no one else knows.

[@noelstarchild]

Totally fascinating upload Mr Cain. Thanks a bunch.

[@jamesdubben3687]

Spectroscopy seems to be the lifeblood of astronomy. Could you interview someone that knows history, current techniques and future tech in the field?

[@ReinReads]

From my time in a chemistry graduate research lab over a decade ago one of the most challenging things is interpreting the curves. I’ve began to wonder if AI/neural net computing might be the ideal tool for this. I find most discussions around AI to be mind numbing, but how it could be applied to spectroscopy would be interesting.

[@TanyaLairdCivil]

Shine on, you crazy diamond!

[@ilkoderez601]

This channel is great. I've always been a fan, you write good articles. I hope you keep this channel going, I'll be here to like your videos. Great guest!

[@sonkefh]

Very Awesome conversation!!! Thank you both!

[@guystarbuck2686]

Fascinating!!! Always learn something new every time i watch this channel. Keep up the good work.

[@lucashouse9117]

This is so fascinating. Great interview as always!

[@adolfodef]

08:48 If a "Black Dwarf" was detected, the most _logical_ conclusion would NOT be that "the universe is way older", but rather: a) "Tunnels" connecting to other (older) universes existed at some point (at least the "exit" points going into our universe), big enough for a star to go through it without suffering "spaguetification". b) Time-Travel is possible (this Black Dwarf was "sent" from the future), meaning it likely contains a lot of DATA inside. c) There is a "process" that can extract (almost) all the energy of a star. This is just a "cold campfire" left behind by an "errant" entity from a Kardashev III+ Civilization.

[@AnkitGusai]

This was such an interesting interview. Thanks.

[@TommySaucierPlourde0]

«I want to push back on that diamond thing.» Wut a surprise !!!

[@fep_ptcp883]

I'll say that to my wife tomorrow

[@TheBiggreenpig]

@@fep_ptcp883 Are you an aspirant astronomer? Because you'll likely see stars.

[@Grumhead]

Very good explanation.

[@nathanielbyrne1132]

love these deep dives

[@pjbth]

8:05 wait.....you can have solid plasma? My mind was just blown

[@Milan_Openfeint]

I was wondering about that. By Simon's definition, ordinary copper is a plasma too since it has free electrons.

[@AliHSyed]

Awesome topic

[@JamesCairney]

This was really interesting

[@Enkaptaton]

I had to laugh out loud when I heard Fraser's first question. This guy knows exactly how to ask a scientist

[@bmobert]

Fascinating! Thinking about aliquid and solid or even crystalline plasma just makes me want to ask more questions. Vey cool! Thank you

[@nielsandersen6164]

By his definition of plasma, amorphous metals (metallic glass) are also plasma. I was always told that plasma is a an ionized gas. Have I been lied to?

[@annsidbrant7616]

I take a huge interest in blue objects of the universe, primarily blue stars like the Orion Belt stars, but also blue galaxies like M101 and blue planets like HD 189733b. Naturally I also take an interest in white dwarfs, because they are often quite bluish. I am of course aware that white dwarfs cool over time and become less blue and more yellow and red. But I had never before heard that most white dwarfs have cooled so much that they are cooler than the Sun, and I'm not sure I believe in it. I googled the typical surface temperature of white dwarfs, and I was told that their typical temperature is 10,000 K. That is the same temperature as Vega. Of course, at 10,000 K the white dwarf has already cooled down mightily, because they will have started out at a 100,000 K or hotter (perhaps even 1,000,000 K or more). Still, at 10,000 K Vega looks decidedly blue-white when observed through a telescope, and it certainly doesn't look yellowish. So a white dwarf of 10,000 K would look blue-white too, and it would be 4,000 K hotter than the Sun. I also googled "white dwarfs in globular clusters", and I found a Hubble image of white dwarfs in globular cluster M4. In the Hubble image, the white dwarfs all look bluish. So please explain how most white dwarfs in the universe can be cooler and more yellow than the Sun, because this is the first time I have ever heard that claim!

[@petevenuti7355]

Apparently it's because they're too dim to see without a massive or IR telescope. In other words, we can't see most of them?

[@douglaswilkinson5700]

All images taken by both Hubble and JWST are "black and white" with shades of gray in between. Color is added to make the images more appealing. Researchers use only the black & white images (Fraser interviewed an image specialist awhile back.)

[@annsidbrant7616]

I guess my question is this: Has there been enough time for a majority of the white dwarfs that have ever formed in the Universe to cool down enough to become cooler than the Sun?

[@shinobi3673]

Technical answers in a second language are difficult, but he was trying!

[@jim.franklin]

Interesting topic, I do wonder if there is more than one process going on - nature seems to hate a vacuum, or a single pathway to a solution, so I would hazard that there may be several pathways that allow the WD to stay "hot" for longer than we originally thought. Another good interview @frasercain, very informative.

[@user-yq3tf8mx1x]

What if planet is formed after star converts into the white dwarf? And it will be in habitable zone. Would life be possible there?

[@abstractedaway]

Last I perused this topic, it seemed the odds are slim, but not impossible. The habitable zone is very close to the white dwarf, meaning tidal locking is assured. In fact, the tidal forces and radiation are intense.

[@ronniabati]

If the temperature of Neon-rich white dwarfs remains relatively constant for billions of years, could newly formed planets (post red giant) potentially evolve into habitable worlds orbiting the white dwarf?

[@hamjudo]

It probably depends on what stuff is spewed out by the white dwarf. If the white dwarf emits atmosphere destroying stellar flares every few million years, then surface life would be difficult.

[@ioresult]

I would have thought that just the crystallisation process would be enough to stop the cooling (like when water freezes, it says at 0° until all water is solid). What's the proportion of energy output just from crystallisation versus enrgy output from gravitational potential? I would think that there would be several stops in the cooling process. For example, cooling would resume once neon concentration reaches a certain point, then stops when it starts crystalizing again and when another element starts concentrating in the bottom of the gravitational well. Etc.

[@josephboisvert8213]

Wow this man is well informed and clearly very knowledgeable… No I wasn’t thinking of you Fraser.. y

[@adolfodef]

This is good news for our descendants living at the END OF TIME® This "insulation" keeps some of the thermal energy White Dwarfs trapped for much longer times (allowing for a more efficient collection overtime), specially considering that the longer they get to retain it, the cooler the cosmic background radiation becomes & that tiny difference means quadrillions of years of computation.

[@savetheplantet5799]

I wonder if neon gas is concentrated in a trap between other gasses to make a thermal infinity lamp??? And will plateau to cooling process for a good while? If there are molecules still dancing in the trap then the neon stays lit? Or a model like this happening using other forces at play?

[@savetheplantet5799]

That is sick! I was at least on the right track. Maybe add the mechanics of a lava lamp and there's the motion indicating evidence of the neon theory! And if this is even close to the truth of this phenomenon? Then we would know how to search for expiring lamps to indicate maybe a huge change in the theory of the age of the universe. Finding just one black dwarf would be revolutionary.

[@HobieH3]

I get the feeling he wasn't crazy about the 1a supernova discussion. Too mainstream. He's definitely a White Dwarf Hipster. lol. Very cool.

[@IanBourneMusic]

As well as the "not cooling" mechanism mentioned here, wouldn't crystallisation itself release heat, so slowing the cooling even more?

[@DavidsDreamFactory]

Can we make a space interferometer with an array of telescopes to use the Sun as a gravitational lens? In my head you could adjust the distance between the telescopes to focus and avoid having to go out to the ludicrous distance of 550au

[@jamysmith7891]

Crystalline plasma, interesting indeed

[@MCNarret]

Be me, an alien civilization, cooling white dwarves to scare other aliens into thinking the universe is older.

[@garman1966]

Fraser Cain. I have a question unrelated to this post. I have an an explanation for the galaxy rotation curves that doesn't require dark matter. Imagine yourself as a person standing on Earth and feeling a normal amount of gravitational pull. Then imagine that you could fall through the planet without any friction or resistance to your fall. You would fall toward the center until you passed the center and then you would slow down as you came up to the surface on the other side. What if you were able to orbit the center of Earth with an orbital radius of say a kilometer? The gravitational attraction would be very small, as if you were orbiting an asteroid with a kilometer radius, and you would have to orbit quite slowly to not fly away. I think the same goes with a galaxy. Instead of normal planetary gravitational interactions between a star and it's planets where the inner planets orbit much faster than the outer ones because all the attraction is toward the star, in a galaxy the mass is distributed more throughout. Instead of it all being in the center, it's more like a spinning cloud of mass consisting of the whole thing where mass isn't concentrated at the center, like being inside the Earth as said before. Wouldn't this understanding result in the relatively similar orbital speeds of the outer and inner stars that we assumed we needed some kind of dark matter to explain? I didn't mention the SMBH's because from what I understand, their mass is very small compared to that of the rest of the galaxy and wouldn't affect rotation curves a great amount.

[@justinhannan1713]

This isn't a simulation. The linked clip shows [after zooming in] a few stars orbiting close to the SMBH at the center of our galaxy. m.kzbin.info/www/bejne/jnKadHSMophksJI

[@garman1966]

@@justinhannan1713 I understand that the stars close to the SMBH would orbit faster and faster the closer they got. The SMBH mass is a tiny fraction of the overall mass of the galaxy though, and I don't think it affects the bulk of the rest of the stars in it. Stars orbiting close to the SMBH act more like planets orbiting a star.

[@nirorbach8046]

The planet wreckage reminds me a field of archeology, when more destructive scenario leads to better understanding of the culture/planet that was destroyed 🤣 Anyway thanks for another interesting interview

[@barthennin6088]

Great video! At about the 8 min mark, he says a plasma can be both a plasma and a solid... I thought a "plasma" was a 4th state of matter (solid, liquid, gas, plasma)... So is a 'solid plasma' a 5th state of matter? And are there liquid plasmas and gaseous plasmas?...He also says a "plasma" is just where the electrons are removed from the atoms... So doesn't that mean we could consider any electrically conductive metal a plasma? (as the electrons flow free of or removed from their atoms?).

[@BrandyBalloon]

My brain might go supernova trying to think about solid plasma 🤯

[@douglaswilkinson5700]

Neon? I thought it is produced by carbon/oxygen fusion at about 600M K in stars 8 to 10 times more massive than our Sun. So the neon must have been one of the metals in the nebula in which our Sun formed.

[@ioresult]

Hey you're just a couple hours drive from Victoria, you could have met in person?

[@frasercain]

Very true. Maybe I'll drop in next time I'm in Victoria.

[@sulljoh1]

Plasma can be solid?

[@deandeann1541]

"White dwarfs...are way too hot to be at such cool temperatures." (this was said somewhere between the 8 and 9 minute mark) - I just would not know what to say in reply to that statement.

[@denijane89]

So I decide to return to my studies on white dwarves and suddenly, they are all over the internet. Until this week, I had no idea that there's no simple way to estimate the WD brightness and you have to do full simulation with a bunch of assumptions. That's quite interesting...

[@arubaga]

Fission based heating seemed to be more likely.

[@Cammymoop]

Could you put a little icon in the thumbnail so we can tell which videos are space bites, interviews, or q&a videos?

[@Cammymoop]

just noticed the little q&a text in the corner actually, maybe just a little higher so it doesn't disappear in the corner!

[@user-fq6rh2xk8n]

Could there be a habitual zone around a white dwarf

[@frasercain]

Yes, absolutely.

[@sirbarringtonwomblembe4098]

'Dwarves'. I know it's such a little thing, but I feel that it needed to be said. Sorry if I sound a bit short.

[@frasercain]

The plural for white dwarf is white dwarfs, which is different from fantasy dwarves. Strange, I know.

[@paulcooper8818]

The explanation starts at 13:37, an interesting idea.

[@tomholroyd7519]

So planets that survive the formation of the white dwarf could potentially last for tens or hundreds of billions of years? And where is the habitable zone around a white dwarf?

[@100-pc-notbot]

post-mortem geochemistry :)

[@t.a.r.s4982]

Is Simon french or Canadian? His accent sounds like mine ^^'

[@frasercain]

French Canadian

[@michalchik]

I agree that the neon 22 fall might contribute some energy to the white dwarf but I'm puzzled as to why the primary consideration isn't the enthalpy of fusion when you trans form from a liquid plasma into a solid plasma. All transitions from liquid to solid are significantly exothermic. I'm wondering if these guys are thinking too much like physicists and not enough like chemists. If I saw a container of hot liquid that suddenly stopped cooling down and kept a stable temperature, the first thing I would think of would be that some of it was solidifying.

[@simonblouin]

The latent heat release is taken into account. It's not enough to explain the cooling delays observed in the anomalous white dwarf population.

[@michalchik]

@@simonblouin thank you for the reply. I'm surprised that the neon 22 fall is significant in magnitude compared to the latent heat of fusion. What are the energy ratios between heat diffusion and the potential energy of the neon 22? How certain are you about the heat of fusion given that this is a transition between two exotic states of matter?

[@simonblouin]

@@michalchik it varies from star to star (depending on the mass and composition), but you get roughly 10x more energy out of neon-22 transport to the center of the star than from latent heat release. Apart from numerical simulations, there is strong observational evidence that the latent heat release is not more important than that. The key is that all white dwarfs crystallize at some point, and yet we only observe this multi-billion-year cooling delay for a fraction of the white dwarf population. The extra energy must come from something that affects only a fraction of white dwarfs, so that rules out latent heat. (Neon-22 transport on the other hand depends on the exact composition of the white dwarf, and not all white dwarfs have the same composition.)

[@michalchik]

@@simonblouin that makes sense. Thank you

[@chrismichelsmusic]

As I watch the moon sink in the sky, am I witnessing the spin of the Earth?

[@frasercain]

Mostly, but the different location each night shows you that it's in orbit

[@knighthunteroi]

Wouldn’t a white dwarf still have insanely powerful gravity that would crush any life that could be on it.

[@Kinann]

How much of the original star mass is left? If the Earth survived our sun's conversion to a neutron star, where would the new orbit be?

[@Kinann]

researched myself, approximately 50% for a sun sized star.

[@2SHARP4UIQ150]

Dr. Simon Blouin says most Dwarf are cooled. Statistically, on how many Dwarf we have data.?

[@lyledal]

Did you mean "Metallic hydrogen" in the core of Jupiter?

[@sadderwhiskeymann]

1

[@douggolde7582]

I’m not dead yet.

[@archmage_of_the_aether]

The "just because it's a crystal and there's carbon doesn't make it a diamond" schpiel was quite endearing.

[@JavSusLar]

I don't know if it can be measured with our current technology, but do white dwarves emit neutrinos?

[@zippythinginvention]

Wait. States of matter: solid, liquid, gas, plasma, etc. And, this guy is saying that a material can be a solid and a plasma simultaneously? That's confusing...

[@robertsunde7973]

Wouldn’t the UV radiation sterilize any planet orbiting the star, at least those not tidally locked?

[@ZOMBIEHEADSHOTKILLER]

"plasma can also be a solid" What?! thats crazy!.... this is news to me.... whats an example of a solid plasma? is he saying a white dwarf is a solid plasma?

[@RectalRooter]

@frasercain Question With the caveat - Not allowed to use previously used arguments to prove religion. In the court of law. Can science be proven it is not a religion ? Or will believing science always be doomed to a leap of faith ? Does this thought experiment intrigue a science communicator ? For context of my thinking this question up. It started after watching Bill Nye “the Science Guy” tours the Ark Encounter show / movie. How Ken Ham kept saying " Air Quotes "" Mainstream science " It felt like he was using his own life experience and personal beliefs (( like all of us do )). Mainstream science equals the Vatican's role in religion and the priest / monks job is to convince people of the Vatican's beliefs, making the scientists role to convince people science is correct. Because if religion is all muddled up with different kinds of religious beliefs, then science can be muddled in the same way i.e pseudoscience vs. science. Because I automatically think every science communicator has an explosive orgasm everytime they successfully interpret the usually bland science to a person in an easy and understandable way. Does this make it 1 of the scientist communicators holy grail questions ?

[@frasercain]

The scientific method is a very structured way of exploring nature. It's self correcting since it's always requiring evidence to support hypothesis. At the very base level, you've got to have faith in the method, but then, you use that method all the time in your daily life.

[@fep_ptcp883]

​@@frasercainalso the very scientific method can be perfected over time. There must be no dogma in science, as opposed to religion and its fixed anchors of "truths" estabilished by sacred writings or traditional principles

[@RectalRooter]

@@frasercain I agree with you. But did you forget that your not allowed to use previously used arguments to prove religion ? How to say this - not sure I will be able to type out what's in my mind. I think this is an unanswerable question. That makes you think of both sides of a theory.

[@RectalRooter]

The BIBLE is a very structured way of KNOWING and UNDERSTANDING nature / life. All the answers you need is in the bible.

[@RectalRooter]

@@fep_ptcp883 Can your comment be seen as dogma ? Remember the question is. In the court of law. Can science be proven it is not a religion ?

[@truvc]

White dwarves

[@frasercain]

en.wiktionary.org/wiki/white_dwarfs

[@Thomas-yr9ln]

They prefer to be called little stars. Dwarfs is not politically correct 😂

[@lovepeaceandrespect8808]

you tried your best fraser, but the guy is hard to understand, and finishes sentences on a low quiet note,hope the guy learns to speak up and get some confidence in his voice.

[@frasercain]

Many of the people I interview are doing this for the first time, so it's understandable that they're not practiced.

[@JMOUC265]

@@frasercainI agree with you, Fraser. However, as the interviewer can’t you take remedial measures to help offset deficiencies of the speaker and his/her equipment? I look forward every week to your podcast versions of Q&A, Space Bites, and Interviews. It is very disappointing when the audio is practically unintelligible. Your voice and diction come through always. The problem is with the person or the equipment being used by the person being interviewed. In contrast, I listen also to Planetary Radio Podcasts and their audio is almost always 5x5 and perfectly understandable! They and their guests sound very professional. I don’t know if they are, but they sound great. I hesitate to leave this post because you have been doing Universe Today for a very long time and you’re the expert journalist, but I would appreciate an improvement in the audio quality of interviewed guests. Respectfully, an appreciative listener.

[@PaulPassarelli]

The topic is interesting, and novel, but I'm giving the video a thumbs down for not editing the talking head (Blouin) ramblings down to ~5 minutes.

[@MajSolo]

oh dear a video adding a new component to how we see things. His videos are also bloated like a star. Instead of a interview why Frasier just listen through this and present the NEWS in5 minutes?

[@frasercain]

Because I wanted to learn more about white dwarfs. Feel free to skip it.

[@MajSolo]

@@frasercain you are polite.

[@longboardfella5306]

He does that in SPace Bites - and in his newsletter. These are for deep dives with actual researchers

[@JamesCairney]

I think this complaint beats the "it's snooker, not billiards" complaint hands down.

[@frasercain]

We just recorded space bites and included a 5 minute segment on it. We also did an article on Universe Today that covered it if you like your news in text form. It's in my newsletter, and I shared a 100-word synopsis on my Mastodon feed. So I covered the same story in 5 different styles to meet everyone's need.

[@tactileslut]

🎵 Shine bright like a white dwarf🎵