Modern amateur astronomical telescopes are both powerful and affordable.
Spectroscopy - in which the light a star is broken down into a
rainbow-coloured spectrum - is becoming more and more popular as
instruments and techniques improve with technology. Spectroscopy can
tell us a great deal about a star - not the least what it is made of,
and how fast it is travelling away from us. Practical Amateur
Spectroscopy contains everything an amateur astronomer needs to know to
begin observing, but goes relatively deeply into the subject for those
who are already involved.