Life might get dull at the core of M15 [
http://antwrp.gsfc.
] but the sky would always be bright with [
http://starchild.gs
StarChild.html ] stars! In fact, only 40,000 light-years away in the constellation Pegasus, M15 is one of the most densely packed globular star clusters [
http://antwrp.gsfc.
] in our Milky Way Galaxy. This stunning [
http://heritage.sts
displayngc7078.html ] Hubble Space Telescope image of M15 [
http://heritage.sts
ngc7078table.html#fa cts ] shows thousands of individual stars across the central 10 or so light-years of the cluster, also cataloged as NGC 7078. Yet even the Hubble's sharp vision [
http://hubble.stsci
] can't clearly separate the stars at this cluster's core [
http://xxx.lanl.gov
]. Globular star clusters harbor from a hundred thousand up to a million stars and roam the Milky Way [
http://www.rog.nmm.
] halo. Like most globulars, M15 is [
http://heritage.sts
ngc7078.html ] filled with ancient stars, about 12 billion years old compared to the Sun's estimated 4.5 billion years. Its cool red giant stars appear yellowish in this color composite image. Unlike most globulars, M15 displays a planetary nebula [
http://www.astro.wa
], the briefly visible gaseous shroud of a dying star. Can you pick [
http://antwrp.gsfc.
] it out? Cataloged as Kuestner 648, M15's planetary nebula [
http://heritage.sts
ngc7078table.html#ca ption ] is the round pinkish cloud at the upper left.
Explanation
Life might get dull at the core of M15 [
http://antwrp.gsfc.
] but the sky would always be bright with [
http://starchild.gs
StarChild.html ] stars! In fact, only 40,000 light-years away in the constellation Pegasus, M15 is one of the most densely packed globular star clusters [
http://antwrp.gsfc.
] in our Milky Way Galaxy. This stunning [
http://heritage.sts
displayngc7078.html ] Hubble Space Telescope image of M15 [
http://heritage.sts
ngc7078table.html#fa cts ] shows thousands of individual stars across the central 10 or so light-years of the cluster, also cataloged as NGC 7078. Yet even the Hubble's sharp vision [
http://hubble.stsci
] can't clearly separate the stars at this cluster's core [
http://xxx.lanl.gov
]. Globular star clusters harbor from a hundred thousand up to a million stars and roam the Milky Way [
http://www.rog.nmm.
] halo. Like most globulars, M15 is [
http://heritage.sts
ngc7078.html ] filled with ancient stars, about 12 billion years old compared to the Sun's estimated 4.5 billion years. Its cool red giant stars appear yellowish in this color composite image. Unlike most globulars, M15 displays a planetary nebula [
http://www.astro.wa
], the briefly visible gaseous shroud of a dying star. Can you pick [
http://antwrp.gsfc.
] it out? Cataloged as Kuestner 648, M15's planetary nebula [
http://heritage.sts
ngc7078table.html#ca ption ] is the round pinkish cloud at the upper left.
Explanation