Sunday, April 17, 2011

The Owl and the Cigar

Click on the Images for Larger View
At the upper left of this image is the spiral galaxy M108 and at the lower right is the planetary nebula, M97, also known as the "Owl Nebula".  Both of these object are in the constellation Ursa Major, now seen high in the sky during this Spring season.

Looking like a big, fat cigar, M108 is a spiral galaxy viewed edge on.  Unlike most spirals, there is no bright central bulge seen here, apparently because the there is so much dusty matter hiding it from our view.  These dusty knots are easily seen in the enlarged image.

The two dark spots make this nebula look like a spooky owl.  Classified as a planetary nebula, it is no planet, but a star toward the end of its life.  The star in the center of the nebula is literally blowing its outer layers into space creating an ever enlarging bubble.

Even though it may seem like these two objects are relatively close to each other, it is far from it.  The Owl Nebula is 3,000 light years from us and well within our Milky Way galaxy, but M 108 is about 45 million light years away, 15 thousand time further away than the Owl.  If you look real close at the enlarged image and your monitor is not adjusted too dark, you'll see a very small galaxy to the lower right of the Owl (right next to a star).  Just to the left of the Owl are a few even fainter galaxies all at enormous distances from us.

In this graphic of Ursa Major, there is a small rectangle just below the bowl of the Dipper.  This is the area taken up by the top picture.

The almost two hour exposure of the image is a combination of 11 ten minute shots taken with my 190mm Mak/Newt f/5.3 telescope.

3 comments:

  1. Tom, I am interested in the M108 and M97 photograph. Would you be kind enough to share with me the technical details of that photograph. What telescope, what lens, seeing conditions and location if possible.

    I went out to the Powell Observatory site - in Louisburg Kansas last night and the weather was clear, but I wasn't able to see any detail on the M97 - I own an 8inch Dobsonian telescope - and I have heard people able to get detailed views with it.

    However, if it was the location that causing "seeing" problems, I'd like to have your take on the best star gazing location in the Kansas Missouri area.

    Much Thanks,

    - Sanket

    sanket.korgaonkar@gmail.com

    ReplyDelete
  2. Hi Sanket: The image was taken from my home in Cleveland, Missouri, only about 10 miles from Powell Observatory. My CCD camera (Q453 by CCD-Labs) was attached to my Maksutov/Newtonian made by Orion Telescopes. It has a 7.5" f/5.3 mirror with a Maksutov corrective plate in the front to correct for coma. The scope is mounted on a german equatorial mount made by Parallax Instruments. I took 12 images, of which 11 were good. The exposure for each image was 10 minutes. The system was guided with a homemade guidescope made from a 50mm finder and an autoguider camera also from CCD-Labs. This autoguider is the exact same autoguider that Orion Telescopes sells, called the Starshoot. As far a seeing details of of the Owl Nebula. You should be able to see at minimum, the two dark "eye" of the Owl. Other detail would be much harder since it is composed of wispy nebula. Kind of like trying to see detail on a cloud. It is easier to get details with photographs, since they can be adjusted to bring out the subtle details. You might try a light pollution filter. These filters darken the sky giving the nebula more contrast making detail easier to see. The best place for observing the night sky is anywhere away from city lights. Astronomical Society of Kansas City members (who build Powell Obs.) has 40 acres near Butler, Missouri with excellent dark skies. It is gated so we don't get interrupted by the public. If you are not already a member of the ASKC, you might want to consider joining just for this site.

    ReplyDelete
  3. VaporFi is the most recommended electronic cigarettes supplier out there.

    ReplyDelete