Questions tagged [brown-dwarf]

Questions about sub-stellar objects that are like stars but never achieve nuclear fusion because they are too low-mass.

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Why have brown dwarf classes been dubbed L, T and Y?

The classes used to categorize stars (O, B, A, F, G, K, M) are in a bizarre order for historical reasons. Stars were labeled based on the spectral lines that were visible, then the categories were put ...
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How are Y-dwarf spectral subtypes defined?

It is often stated that the spectral subtype indicates the relative position between spectral types, e.g. G5 being halfway from the start of spectral type G to the beginning of spectral type F. Given ...
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Would it be possible for life found on moon of rogue planet

I have heard that there are at least three Basic requirement for life exist in the universe, they are: Source of Energy Complex chemistry (including solvent/medium for chemical reaction) Protection ...
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Brown Dwarf Cloud Models

There has been research that suggests that the changing brightness of Brown Dwarves are due to bands of Iron/Silicate clouds. Several models have been made that supports that hypothesis. My question ...
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Are we looking for brown dwarfs where the dark matter has to be?

We have been repeatedly assured that their ain't enough brown dwarfs to account for all the dark matter in our galaxy. My question is have we been looking in the right places? Or in more detail. ...
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Existence of planets larger than their host star?

The mass region of objects between ~ 0.5 Jupiter masses and 80 Jupiter masses (gas giants through to brown dwarfs and red dwarfs) is typified by an almost flat relationship with object diameter. There ...
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Are brown dwarfs which dont sustain any fusion considered stars?

I was reading about the coolest stars , and surprised to find about stars with a surface temperature lower than a candle, like 2MASS 0939-2448 A/B, of about 100 celsius like CFBDSIR 1458+10B and even ...
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Brown dwarf magnetic activity

I have not been able to find an answer to my question through google, and therefore ask it on this medium. Do brown dwarfs have spots and faculae similar to other heavier stars?
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Are brown dwarf masses notoriously difficult to measure?

The Next Big Future article Rogue Exoplanet 12.7 times bigger than Jupiter is 20 light years away SIMP J01365663+0933473 has a magnetic field more than 200 times stronger than Jupiter’s. The object ...
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Very near GAIA DR2 sources - has Proxima Centauri been dethroned?

I made an extract of GAIA DR2 data for parallaxes greater than 500mas. Surprisingly I see a very significant number of sources with parallax greater that 1000, making them much closer than Proxima. ...
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Jupiter vs brown dwarf star

What would happen to Jupiter if a brown dwarf star collided with it, and vice versa what would happen to the brown dwarf star?
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How close to a brown dwarf would a planet need to be to receive as much light as Earth?

How close to a brown dwarf would an orbiting planet need to be in order to receive as much sunlight as Earth receives from the Sun?
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Is there such a thing as a black dwarf

Does such a heavenly body exist called a black dwarf? It would be a Brown dwarf that has cooled to the point it no longer gives off heat or light.
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If two binary brown dwarfs began to exchange gas with each other, would they both ignite into stars?

If two brown dwarfs got close enough to exchange gas with each other, could it trigger nuclear fusion within their cores? Is it possible for two brown dwarfs to orbit so closely and become a ...
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“Turn on point” for fusion?

I've read that when a body reaches about 13 times the mass of Jupiter that deuterium fusion starts and the body becomes a brown dwarf instead of a planet. I have a multiple question. Are there any ...
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What is the closest heavenly body to our solar system

What is currently the closest known heavenly body, brown dwarf, rogue planet or other to our solar system? At one time it was Alpha Centauri.
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How do we calculate heat flow or cooling rate for no fusion brown dwarf star?

I was reading this article and it said something that didn't sit right with me. "SIMP0136 still gives off light mostly in the infrared wavelengths, as its temperature is now approximately 830° C (1,...
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508 views

Concerning the “Lithium test” for Brown Dwarfs

Both low-mass PMS (pre-main-sequence) stars and young brown dwarfs can fuse lithium in their cores and the lithium can be depleted throughout the star/brown dwarf very quickly. Wiki. Then the Li I ...
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How large can a ball of water be without fusion starting?

How large can a ball of water be without fusion starting? Peculiar question: some explanation might be necessary. My young son is into ‘space’ and astronomy. One of his posters says that Saturn could ...
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How do I understand a brown dwarf with a M-type spectrum?

There are a large fraction of M dwarfs which are claimed to be brown dwarfs. Why do we still use M-type and not create a new stellar type like L, T and Y? The main signature of M is TiO absorption ...
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V471 Tauri's circumbinary brown dwarf non-observation; Applegate, or over-restrictive assumptions?

tl;dr Has the brown dwarf observation been disproven? I have just started reading about the interesting object V471 Tauri. The first two sentences of the introduction to The V471 Tauri System: A ...
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Can a Y dwarf star undergo a supernova?

Y dwarf stars have sub-zero temperatures, so I became curious how a star like these dies out and if is could go supernova.
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Life forms in brown dwarf atmosphere

Some of brown dwarfs generate the enought amount of heat to warm their atmosphere up to 300 K. This is a condition to liquid water and, possibly, organic life forms. Is where are a some studies about ...
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Why can't our Sun be a binary with Jupiter as a T or Y dwarf?

I just learned about Brown Dwarfs, they are "failed" stars, they narrowly missed the stellar mass mark. I learned that Y Dwarfs have temperature as low as 80 Fahrenheit (The first one found by WISE ...
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Is it possible to have a star orbiting around a brown dwarf?

I know a single star is almost surely more massive than a single brown dwarf, but consider a case: a very small star is orbiting a very massive brown dwarf which has a very massive moon, such that the ...
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Could there be a brown dwarf in our solar system? [duplicate]

Is it possible that a brown dwarf object could be orbiting our star and undetected so far by wise surveys?
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We are sure that there are no brown dwarfs closer than ______

I don't quite know how to word this question. How close could a brown dwarf be to us and have gone undetected until now? Or maybe, with what probability are we sure that there is no brown dwarf ...
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Plausible? Brown Dwarfs are rogue celestial bodies because they absorb all light due to their thick layer of matte black soot [closed]

My theory of why Brown Dwarfs are the rogue celestial bodies that travel through galaxies without a set course. My first theory would be their matte black in color due to a layer of soot.Light does ...
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Is the mechanism of solar flares on red dwarfs and brown dwarfs the same as that on the Sun?

The Sun has solar flares that are caused when there is a magnetic reconnection in the Sun's atmosphere, causing a loop of magnetic field to be ejected at high energy, along with a large number of ...
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What is the largest possible size for a brown dwarf?

What is the largest possible size for a brown dwarf before it has enough mass, capable of sustained fusion, thus becoming a star?
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Why aren't brown dwarfs the dark matter?

There seems to be not enough matter to account for the fact that the speed of some stars located far from the Galaxy center is almost the same speed as those stars found nearer to the center of the ...
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Brown dwarfs and planets

As far as I know, a brown dwarf is a 'star' whose core never underwent a fusion reaction, so it never became a star. So I was wondering if, apart from orbiting a star, is there any difference ...
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Could we actually freeze a star?

I read an article recently that said NASA has discovered a brown dwarf that has frozen. If we had the technology, resources, and supplies, could we actually freeze a star and stop it from burning its ...
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Mechanism for Brown Dwarf Fusion

I've read (at here, among other places) that during the Degenerate Era, star formation will end and the last stars will go out. But it was noted that there is still the possibility of star birth, ...