| "The sky is the ultimate art gallery just above us." - Ralph Waldo Emerson (1803 - 82) |
Astrophotography by Jason Jennings |
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| Galaxies :: SagDEG | |
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| Resolutions Available: 1084x552 : 2709x1380 : 4515x2300 | |
| Object | SagDEG |
| Comment |
What appears to be a typical star field in the constellation Sagittarius resides one of the closest galaxies to our Milky Way at a mere 50,000 light years away. The Sagittarius Dwarf Elliptical Galaxy (aka SagDEG) is so close in fact that stars associated with this galaxy are located in the outermost regions of our Milky Way's spiral disk. Despite its proximity to the Milky Way, it was not discovered until 1994. The galaxy has a very low surface brightness and is partly obscured by the Milky Way's central region of dense stars and dust. The globular star cluster M54 at center of the image coincides with one of the galaxy's two brightest knots and is likely to be the first extragalactic globular cluster discovered. In 2011, a group of astronomers identified that the spiral arms of the Milky Way galaxy could have been generated after two major collisions with SagDEG over the past billion years. This interaction is likely to have stripped much of SagDEG's stars, eventually merging them into the Milky Way. A third collision between the Milky Way and SagDEG is expected to occur within another ten million years. This image is a LRGB two frame mosaic. |
| Optics | Takahashi FSQ-106ED F/5 (530mm FL) |
| Camera | Apogee Alta U16M - 1x1 bin (image scale: 3.5 arcsec/pix) |
| Mount | Software Bisque Paramount ME |
| Exposure | Total exposure time: 15 hours |
| Date | September 2011 |