June and October 2001

The following images were obtained with an SBIG ST-7E CCD and a Meade 10-inch LX200 Schmidt-Cassegrain telescope. Deep sky LRGB images were obtained on October 14, 2001 UT and employed an f/6.3 focal reducer yielding an effective focal length of 64 inches and north is at top, east is to the left in all pictures. All celestial coordinates are for epoch J2000.0.

M27 (NGC 6853) The "Dumbbell" Nebula. RA = 19h 59m 37s; Dec = +22d 43' 20". One of the most famous planetary nebulae in the sky. The object lies in the constellation of Vulpecula (the vulture) and is estimated to be 280 pc (900 ly) from the earth. It has angular diameter of about 400" (about 2.5 ly if the distance estimate is accurate). The nebula is expanding at a rate of about 28 km/s. Ultraviolet radiation from the central star of the nebula, which has a surface temperature of 85,000 K, excites hydrogen and oxygen atoms producing the nebula. This material was part of the star at one time, but was ejected into space during the dramatic changes that take place after the central star evolved off of the main sequence. The Sun will likely lose material in this manner after it depletes its hydrogen fuel supply in its core in about 4 billion years.

M1 (NGC 1043) The "Crab" Nebula. RA = 05h 34m 31s; Dec = +22d 00' 51". This object is estimated to be 1900 pc (6300 ly) from earth. The nebula is about 6 ly across and is excited into emission by the the stellar remnant of a supernova that was observed and recorded by Chinese astronomers in 1054 AD. Portions of the nebula are expanding at a rate of nearly 1000 km/s. The stellar remnant is a neutron star near the nebula's center and is only about 10 km in diameter with a mass greater than the Sun. The star, known as a "pulsar", spins on its axis 30 times a second and each time a pulse of light can be detected by telescopes. The object lies in the constellation of Taurus (the bull).

NGC 891. RA = 02h 22m 33s; Dec = +42d 20' 48". This edge-on spiral galaxy in the constellation of Andromeda is similar to our own Milky Way galaxy. Our Galaxy would look like this if viewed along its disk. The Sun would be located somewhere in the outskirts of the dusty disk 2/3 of the way from the central bulge of the galaxy. The prominent dark lane in NGC 891, as in our Galaxy, is caused by dust in the disk blocking the light stars in galaxy. This galaxy is believed to be about 9 Mpc (30 Mly) and contains over 200 billion stars. of the way

NGC 7479. RA = 23h 04m 57s; Dec = +12d 19' 18". A face-on barred spiral galaxy in the constellation of Pisces (the fish). Compare this image with the image of NGC 7479 taken with the Steward Observatory 90-inch Bok telescope located atop Kitt Peak, Arizona.