enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Emission nebula - Wikipedia

    en.wikipedia.org/wiki/Emission_nebula

    Planetary nebulae, represented here by the Ring Nebula, are examples of emission nebulae. An emission nebula is a nebula formed of ionized gases that emit light of various wavelengths. The most common source of ionization is high-energy ultraviolet photons emitted from a nearby hot star.

  3. Nebula - Wikipedia

    en.wikipedia.org/wiki/Nebula

    Diffuse nebulae can be divided into emission nebulae, reflection nebulae and dark nebulae. Visible light nebulae may be divided into emission nebulae, which emit spectral line radiation from excited or ionized gas (mostly ionized hydrogen ); [ 25 ] they are often called H II regions , H II referring to ionized hydrogen), and reflection nebulae ...

  4. Planetary nebula - Wikipedia

    en.wikipedia.org/wiki/Planetary_nebula

    NGC 6326, a planetary nebula with glowing wisps of outpouring gas that are lit up by a binary [3] central star. A planetary nebula is a type of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from red giant stars late in their lives. [4] The term "planetary nebula" is a misnomer because they are unrelated to ...

  5. List of diffuse nebulae - Wikipedia

    en.wikipedia.org/wiki/List_of_diffuse_nebulae

    This is a list of diffuse nebulae. Most nebulae are diffuse , meaning that they do not have well-defined boundaries. Types of diffuse nebulae include emission nebulae and reflection nebulae .

  6. Cosmic dust - Wikipedia

    en.wikipedia.org/wiki/Cosmic_dust

    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 ).

  7. Deep-sky object - Wikipedia

    en.wikipedia.org/wiki/Deep-sky_object

    Since the definition is objects that are not Solar System objects or individual stars, examples include: [10] Black holes [11] and active galactic nuclei [12] Nebulae. Bright nebulae. Emission nebulae; Reflection nebulae; H II regions; Diffuse ionized gas; Planetary nebulae; Supernova remnants; Dark nebulae [13] Galaxies [14] Star clusters ...

  8. Eagle Nebula - Wikipedia

    en.wikipedia.org/wiki/Eagle_Nebula

    The Eagle Nebula is part of a diffuse emission nebula, or H II region, which is catalogued as IC 4703. This region of active current star formation is about 5700 light-years distant. A spire of gas that can be seen coming off the nebula in the northeastern part is approximately 9.5 light-years or about 90 trillion kilometers long. [6]

  9. Reflection nebula - Wikipedia

    en.wikipedia.org/wiki/Reflection_nebula

    Reflection nebula are usually blue because the scattering is more efficient for blue light than red (this is the same scattering process that gives us blue skies and red sunsets). Reflection nebulae and emission nebulae are often seen together and are sometimes both referred to as diffuse nebulae. Some 500 reflection nebulae are known.