This immense ball [ http://www.seds.org…] of half a million stars [ http://imagine.gsfc…] older than the sun lies 30,000 light-years above the plane [ http://antwrp.gsfc.…] of our Galaxy. Cataloged as [ http://physun.physic s.mcmaster.ca/GC//mw gc.dat ] M [ http://antwrp.gsfc.…]3 (and NGC [ http://antwrp.gsfc.…] 5272), it is one of about 250 globular star clusters [ http://www.seds.org…] which roam our galactic halo [ http://www.limber.o…]. Individual stars are difficult to distinguished in the densely packed core [ http://antwrp.gsfc.…] but colors are apparent [ http://aibn47.astro…] for the bright stars on the cluster's outskirts. M3's many cool "red" giant stars take on a yellowish cast in this lovely composite image while hotter giants and pulsating variable stars look light blue.
Explanation
This immense ball [ http://www.seds.org…] of half a million stars [ http://imagine.gsfc…] older than the sun lies 30,000 light-years above the plane [ http://antwrp.gsfc.…] of our Galaxy. Cataloged as [ http://physun.physic s.mcmaster.ca/GC//mw gc.dat ] M [ http://antwrp.gsfc.…]3 (and NGC [ http://antwrp.gsfc.…] 5272), it is one of about 250 globular star clusters [ http://www.seds.org…] which roam our galactic halo [ http://www.limber.o…]. Individual stars are difficult to distinguished in the densely packed core [ http://antwrp.gsfc.…] but colors are apparent [ http://aibn47.astro…] for the bright stars on the cluster's outskirts. M3's many cool "red" giant stars take on a yellowish cast in this lovely composite image while hotter giants and pulsating variable stars look light blue.
