What you are looking at is a faint planetary nebula. A planetary nebula is a star near the end of its life cycle. It has already burned up all its hydrogen, helium, and carbon that once fueled the star, and is left with only a very white carbon star. Therefore it still emits intense ultraviolet radiation and this radiation will ionize the gas of the star’s old shell that it is gently ejecting outward, making it glow. Eventually, the star will cool down, and the glow will vanish. Contrary to its name, a planetary nebula has nothing to do with planets. It received its name from early discoveries of nebula when they were considered to possibly be more planets.
This particular image is of planetary nebula NGC 1514. It is part of the Taurus constellation and approximately 1000 light years away from earth with a linear size of about half a light year. Here the light emitted from the white dwarf star can be clearly seen near the center of the image. Surrounding it is a blotchy, blue nebula shell that is slowly expanding away from the star. With a larger telescope or a longer exposure time the ring formed by the nebula’s expanding shell would have been seen more clearly. Scattered about the image are many other nearby stars, including one star that is appears to be merging with the white dwarf star. This is more likely a foreground star.
Bennett, Jeffrey, Megan Donahue, Nicholas Schneider, and Mark Voit. The Cosmic Perspective. 6th ed. San Francisco: Addison-Wesley, 2010. 543-44.
TheSky Astronomy Software. Copyright 1984-2000. Software Bisque.
|Right Ascension (J2000)||04:09:14.7|
|Filters used||blue(B), green(V), red(R), and clear(C)|
|Exposure time per filter||60 seconds in CBVR|
October 26, 2010 (CBVR)