27
votes
Could the Methuselah star be evidence that there was a universe before this one?
First, if the Big Bang did originate with the collapse of a cyclic universe, the collapse reached densities and temperatures sufficient to not only ionize matter from the previous cycle, but to ...
7
votes
Why do we not call black holes black stars or dark stars?
The hypothetical object where gravity is so strong that even light cannot escape was indeed first called "dark star". It was first named as such by John Michell in the 1700s. See Wiki. Note ...
5
votes
Accepted
Reasonable stellar body stats
There is about 1 brown dwarf for every 5 stars. White dwarfs in the field would typically have a mass of $0.6 \pm 0.2 M_\odot$ and a luminosity of $10^{-5}-10^{-3}L_\odot$. Their frequency is about ...
3
votes
What is the distance between Stephenson 2-18 and Earth?
Stephenson 2-18 is in the Milky Way.
It is located about 19000 light years away, but this value is very uncertain. There is a cluster of stars which is somewhere between 25000 light-years and 16500 ...
2
votes
Accepted
Where can I get historical data of tropical longitude of Delta Cancri
Any Planetarium software that simulates precession will tell you this. If you know what to ask it.
Delta cancri has a Right ascension of 8hr 45min (or about 131 degrees). It has an ecliptic longitude ...
2
votes
How can 'HD 140283' be older than the universe?
The most recent age estimates for this stars using improved interferometric estimations of angular diameter (to better estimate the effective temperature) and more sophisticated stellar models are:
$...
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