Posted by JuanPro on .
Q3.2 COLLAPSE TIMESCALE (5 points possible)
Imagine that you live in a distant galaxy far far away. This galaxy is in a different universe, and so may have different cosmology.
It seems that in this distant universe, all galaxies have the same luminosity, which you have worked out is 7.0×1030W.
You are studying a particular galaxy which you have just discovered. You take a spectrum and find that it has a strong hydrogen line at a wavelength of 659.2 nm. In the laboratory, this line occurs at a wavelength of 656.3 nm.
What is the redshift of this galaxy?
You measure the flux from this galaxy and get a value of 3.6×10−18W m−2.
How far away (in Mega-parsecs) is this galaxy?
If you assume that this universe is expanding at a constant rate, how old is this universe? Type your answer in billions of years.