Further Reading / Supplemental Links
- http://www.cfa.harvard.edu/press/2006/pr200611.html
- http://hypertextbook.com/facts/2000/MarissaWager.shtml
- http://seds.lpl.arizona.edu/messier/more/mw.html
- http://www.space.com/scienceastronomy/050816_milky_way.html
- http://seds.org/messier/cluster.html;http://hubblesite.org/newscenter/archive/
releases/star-cluster/ - http://stardate.org/resources/btss/galaxies/;http://casswww.ucsd.edu/public/
tutorial/Galaxies.html;http://www.smv.org/hastings/student1.htm - http://en.wikipedia.org
Vocabulary
binary star One of two stars that orbit each other.
elliptical galaxy An oval or egg shaped galaxy with older stars and little gas and dust.
galaxy A very large group of stars held together by gravity; few million to a few billion
stars.
globular cluster Groupsoftenstohundredsofthousandsofstarsheldtogetherbygravity.
irregular galaxy A category of galaxy that is neither a spiral nor an elliptical galaxy.
Milky Way The name of our galaxy; also the whitish band of stars visible in the night
sky.
open cluster Groups of up to a few thousand stars loosely held together by gravity.
spiral arm Regions of gas and dust plus young stars that wind outward from the central
area of a spiral galaxy.
spiral galaxy A rotating type of galaxy with a central bulge and spiral arms with young
stars, gas and dust.
star system Small groups of stars.
star cluster Larger groups of hundreds of thousands of stars.