Some "dusty" Clouds in The Universe
Our solar system has its own interplanetary dust cloud; extrasolar systems too.
There are different types of nebulae with different physical causes and processes. One might see these classifications:
- diffuse nebula
- infrared (IR) reflection nebula
- supernova remnant
- molecular cloud
- HII regions
- photodissociation regions
- Dark Nebula
Distinctions between those types of nebula are that different radiation processes are at work. For example, H II regions, like the Orion Nebula, where a lot of star-formation is taking place, are characterized as thermal emission nebulae. Supernova remnants, on the other hand, like the Crab Nebula, are characterized as nonthermal emission (synchrotron radiation).
Some of the better known dusty regions in the universe are the diffuse nebulae in the Messier catalog, for example: M1, M8, M16, M17, M20, M42, M43 Messier Catalog
Some larger 'dusty' catalogs that you can access from the NSSDC, CDS, and perhaps other places are:
- Sharpless (1959) A Catalogue of HII Regions
- Lynds (1965) Catalogue of Bright Nebulae
- Lunds (1962) Catalogue of Dark Nebulae
- van den Bergh (1966) Catalogue of Reflection Nebulae
- Green (1988) Rev. Reference Cat. of Galactic SNRs
at
- The National Space Sciences Data Center (NSSDC)
- CDS Online Catalogs
Read more about this topic: Cosmic Dust
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