NGC 524 — a very striking looking, old lenticular galaxy — is the subject of a beautiful new image taken by the Hubble Space Telescope. The very interesting — and truly ancient — galaxy is located in the constellation of Pisces, and lies about 90 million light-years from the Earth.
The image shows the shape of NGC 524 in great clarity — observations which have revealed that the galaxy still maintains some spiral-like motion despite its ‘old’ age.
NASA provides background on the galaxy:
NGC 524 is a lenticular galaxy. Lenticular galaxies are believed to be an intermediate state in galactic evolution — they are neither elliptical nor spiral. Spirals are middle-aged galaxies with vast, pin wheeling arms that contain millions of stars. Along with these stars are large clouds of gas and dust that, when dense enough, are the nurseries where new stars are born. When all the gas is either depleted or lost into space, the arms gradually fade away and the spiral shape begins to weaken. At the end of this process, what remains is a lenticular galaxy — a bright disc full of old, red stars surrounded by what little gas and dust the galaxy has managed to cling on to.
“In many respects the composition of lenticular galaxies is like that of ellipticals. For example, they both consist of predominately older, hence redder, stars. All of their stars are thought to be older than about a billion years, in agreement with their offset from the Tully-Fisher relation (see below). In addition to these general stellar attributes, globular clusters are found more frequently in lenticular galaxies than in spiral galaxies of similar mass and luminosity. They also have little to no molecular gas (hence the lack of star formation) and no significant Hydrogen α or 21-cm emission. Finally, unlike ellipticals, they may still possess significant dust.”
Beautiful image. 🙂