How to measure distances to stars by means of spectroscopic parallaxes on practice? What is the accuracy of measuring distances using this method compared with distances based on HIPPARCOS ...
Is there any handy module to detect emission lines in a spectrum like one we get from the Sloan Digital Sky Survey (SDSS)? You can see there are many emission lines like Ha,OI in the spectrum below. ...
The Lyman-alpha forest is an interesting feature found in the spectra of sufficiently distant objects. This series of absorption lines extends over a range of frequencies, and are a result of the ...