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| Nebulae |
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| Star Makers |
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| Planetary Nebulae |
Reflection Nebulae |
This is one example of a reflection nebula. This is named the Merope (mer-o-pe) Nebula in the constellation Taurus. It is found among the beautiful star cluster named 'The Pleiades' (plea-ah-dees). This star cluster is also known as M45 (Messier Object 45), and as 'The Seven Sisters'.
The dust and gas of this nebula does not emit its own light. It only REFLECTS the light from the nearby star or stars; in this case, from the star Merope. Under very dark skies, with an optically corrected moderate sized amateur style telescope, you can detect this reflection nebula, as well as additional reflection nebulae regions within the Pleiades cluster. To detect even a faint bluish hue though is quite the gig, requiring larger telescopes, and fine optics. Other nebulae will, if at all, show different hues. Reflection nebulae abound in the night sky, and many are found in unisom with Emission Nebulae |
Emmision Nebulae |
| Emission Nebulae - Here is an example of an emission nebula. This is the Rosette Nebula in the constellation Monoceros (mo-nos-er-os). The nebula surrounds a young star cluster. This nebula is emitting its own light, due to the presence of ultraviolet radiation from the very hot young stars that make up the cluster. Ultraviolet radiation excites the atoms in the interstellar dust and gas so that they leap to different energy levels and emit their own form of radiation which can be seen in the nebula's light spectrum. It is not simply reflecting the light from the cluster,it is also emitting its own light. Emission nebulae can be found in many areas of the night sky, the most famous being the Orion Nebula. |
Dark Nebulae |
| Dark Nebulae - Dark nebulae are usually only visible because they hide the light of something in the background that is bright. Dark nebulae are some of the most difficult, but spectacular objects to be seen in the night sky. Among the best examples of this are the Horsehead nebula, the image above, and is located in the constellation of Orion. Dark Nebulae are often an extremely difficult object to view thru a telesope because the background is just barely lighter than the foreground object. Dark nebulae are clouds of gas and dust that absorbs some light from behind them. The light that is absorbed heats up the dust particles, and then these particles re-radiate, or emit, some of the absorbed energy as infrared light (Infrared light is on the opposite side of the light spectrum from ultraviolet). Some of the background light is also scattered into the surrounding interstellar medium and therefore reduces the contrast between background and foreground, making viewing them even more difficult. |
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