Brown Dwarfs, are they failed stars?
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- čas přidán 26. 06. 2024
- What are Brown Dwarfs? Come with me on a journey into the strange world between stars and planets. Along the way we learn that stars can be colours we never thought possible.
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So maybe "Hot Jupiters" around other stars are just Y class brown dwarfs?
Interesting! and I really don't know the answer to that. Thank you for the interesting comment
Are white dwarfs failed neutron stars. Are neutron stars failed black holes? Why do I only hear this when we talk about brown dwarfs?
I think brown dwarfs are more failed stars rather than failed neutron stars. They aren't quite massive enough to form neutron stars. They both share the fact that they don't really give off visible light.
@@LearningCurveScience I don't think you understoord me...Of course Brown Dwarfs are not failed neutron stars. What I meant is: no one calles a white dwarfs "failed neutron stars" because white dwarfs lacked just a little mass in their main sequence to collapse into a neutron star. Etc.
Ah, I think I understand your point now. Yes it is a very good point and I think the answer to this falls under a couple of ideas. Firstly, we as humans are excellent at categorising things. We do this all the time in order to help us understand the universe. We know very well what stars are and what planets are, and we have categorised these objects. Brown dwarfs don't really fall into either of these categories, and so whilst Brown dwarfs are indeed celestial objects in their own right, since they are relatively newly discovered we find it easier to describe them as 'failed stars'. Even though they aren't this kind of language often helps to explain them to people who may not be familiar with them as it provides a framework that they do know to hang a definition of objects that they may not know about. Secondly we do categorise brown dwarfs using the same categorisation system that we use to categorise stars. We can even add them to a Hertzsprung-Russell diagram. Their categorisation as stars means that it is in some way natural to compare them to stars, and since they do not emit light (for most of their lives) it is a natural to ask the question, are they failed stars? In reality, no they are not but it is an enticing question to put on a thumbnail to hopefully get people to watch the video, which is after all what I'm trying to do.
Good video!
perfect comtent
Pretty detailed classification of brown dwarf.
On another note I've create a subreddit for small CZcamsrs science channel.
I've added you to the list. Hope you're cool with that and having the link posted here.
www.reddit.com/r/SmallCZcamsrScience/
It's hard to find small science youtuber. You always get the same major guys when you search for CZcams science on Reddit.
Excellent, thank you. I'll definitely pop by and join your subreddit. Yes it is difficult being a small science CZcamsr. Thanks for the appreciation.
thanks. What's the future for brown dwarfs? are they stable or will they evolve into something else?
sorry if that's a daft question
Thanks for the comment, as brown dwarfs age, they use up their limited fuel that allowed them to shine, so over time brown dwarfs get dimmer and dimmer until they no longer emit visible light at all.
5% of all brown dwarf are thought to merge with another brown dwarf over the next billions of years. Than they will become Red warfs if their combined mass is about 80 Jupiter masses. So we'll get Red Warf stars with 80-160 Masses of Jupiter when this happens and these will shine somewhere between 5- 12 trillion years. These will be the very last stars that will ever shine in our universe. Red Dwarfs that have formed due to a collapsing gascloud will long be gone than. If you might wonder how these will evolve; they will be hydrogen burning tiny stars that will at one point use up their hydrogen. Then they will become brighter and hotter, up to 8000K or so (so much hotter than our sun) and remain that way for another 5 billion years. They will slowly dim into tiny white dwarfs.
Back to brown dwarfs that will never merge....the lighter ones will shine like stars for longer than their bigger brother because Deuterium fusion will be much slower in tiny Brown Dwarfs. After 100-200 million years all their Deuterium has been fused. Since they are much smaller, they will cool down. much faster. The heaviest of all brown dwarfs have unsteady Hydrogen fusion so these are really somewhere between a star and a "not- star". They can be doing this for 10 billion years and all that time they very very very slowly cool down. The largest out there, a 90 Masses of Jupiter Brown dwarf is 10 billion years old but still at 2400K putting it on the edge of an L/M type star. Hotter than the smallest stars ever still! So there is a huge variety.
6:35 what if it had a 2:3 spin ratio
6:40 Where do you get that??
Tidal Lock planets has more chance to have life than those who dont, because there would be always a place between the light side and the dark side where the conditions would be right for life.
Not only that, imagine a big ocean planet, or a thick atmosphere, those could distribute massive amount of heat between sides without issue, Venus does it!! It only rotates 1 time every 240 days or something like that, but the temperature in both sides at 50 km height (where the pressure is 1 atm) is exactly the same (night or day).
Being tidal lock it also means that one side of the planet block most of the radiation that the dwarf star can emit.
A planet with enough gravity would not lost its atmosphere so easy either.
Plus, they could “technically” hold a magnetic field. Since the rotation and orbit is the same and in a very short time, they could hold one.
FLOPS