New Class of Stars Are Entirely Metal
A new theory of star formation suggests that 1 in 10,000 stars must be entirely metal. Now the search is on to find the first
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CrazyNeutrino said:
New Class of Stars Are Entirely MetalA new theory of star formation suggests that 1 in 10,000 stars must be entirely metal. Now the search is on to find the first
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I’d imagine these would be relatively short-lived stars.
Bubblecar said:
CrazyNeutrino said:
New Class of Stars Are Entirely MetalA new theory of star formation suggests that 1 in 10,000 stars must be entirely metal. Now the search is on to find the first
more…
I’d imagine these would be relatively short-lived stars.
Interesting. A couple of issues here. One is that using “metal” in the same astronomical sense of “Carbon and heavier”, we already know that all white dwarfs are entirely metal (except sometimes but not always with a thin atmosphere of hydrogen or helium). 6-7% of stars are white dwarfs, which swamps the fraction 0.01% predicted by the new theory. White dwarfs are long-lived.
But the new theory says that some stars should be formed almost entirely of “metal”. Some of these might be called “|planets” because there is a continuum from the largest planets through the brown dwarfs to the white dwarfs.
The new theory is “obvious in retrospect”, I should have seen it coming, but didn’t. It helps greatly in my understanding of the coolest white dwarfs. The coolest white dwarfs ought to have taken longer to form from stars than the age of the universe – but if the original stars from which they formed had an extremely high metal content then the time to make these coolest white dwarfs is reduced to something quite manageable.
The cool white dwarfs include one that orbits pulsar PSR J2222-0137 and has a temperature of 3,000 K. Link
Another ultra-cool one has a temperature of 3,500 K Link
