[an error occurred while processing this directive]
Calvin Observatory
Home
Hours
Directions
Weather Forecast
Cool Images
Equipment
Publications
Observing Request
External Links
 
Related Links
Wildrik Botjes Planetarium
Physics & Astronomy Department

Astr112 Photography Projects, Fall 2007

Previous imageUp to Class IndexNext image

Ring Nebula in Lyra (M57), Jacob Nydam

Ring Nebula in Lyra

M57 is classified as a planetary nebula and it is commonly known as the Ring Nebula. These types of nebulae form when relatively low mass red giants transform into white dwarfs by gently expelling their outer layers into space, leaving behind a shell of glowing gasses surrounding the dying white dwarf star. The location of this nebula is in the constellation Lyra, thus the name, Ring Nebula in Lyra. The distance to this nebula is 2300 light years and it is expanding at a rate of about one arcsecond per century. The designation M57 comes from the French astronomer Charles Messier's catalogue of Nebulae and Star Clusters. French astronomer Antoine Darquier de Pellepoix was the first to discover it in 1779, and the white dwarf at the center of the nebula was later discovered by German astronomer Friedrich von Hahn in 1800.

M57 is a very colorful object. The colors we see are from the glowing gasses that make up the nebula, gasses such as nitrogen and oxygen (green areas), hydrogen (red areas), helium, neon, sulfur, and argon that have been ionized by ultraviolet photons. These photons come from the still very hot star in the middle of the nebula. The star is not very luminous though, implying that it is not very big either. We can tell what gasses the nebula is composed of by looking at the spectral lines that it radiates. As of now, M57 has a linear size of approximately 1 light year.

References:

Freedman, Roger A., and William J. Kaufmann III. Stars and Galaxies: Universe. 3rd ed. New York: W.H. Freeman and Company, 2007.

“Messier 57.” Students for the Exploration and Development of Space.
<http://seds.lpl.arizona.edu/messier/m/m057.html>

Right Ascension (J2000) 18:53:36
Declination (J2000) +33:02:00
Filters used blue(B), green(V), red(R), and clear(C)
Exposure time per filter 60 seconds in C, 300 seconds in BVR
Date observed

October 20 , 2007 (C)(B)(V)(R)