From Traveller Wiki - Science-Fiction Adventure in the Far future
Jump to: navigation, search
Comp-Prog-Dav-R-Deitrick-Starter-Trav-Page-16 16-July-2018a.jpg

A Nebula is an interstellar cloud of dust, hydrogen, helium and other ionized gases.

Description (Specifications)[edit]

Interstellar clouds are regions of gas, dust, and plasma that have a higher average density than the general interstellar medium. They are typically composed of about 70% hydrogen, the bulk of the remainder being helium with traces of other elements.

Basic Nebula Types[edit]

Interstellar clouds can be classified into 3 general types based on the primary form of hydrogen found within:

  1. Neutral Clouds (H I regions - formed of atomic hydrogen)
  2. Ionized Clouds (H II regions - formed of positively-ionized hydrogen [i.e. "Plasma"])
  3. Molecular Clouds (Molecular Hydrogen - formed of H2)

Hydrostatic Equilibrium[edit]

Under normal circumstances interstellar clouds exist in a state of hydrostatic equilibrium, in which the natural self-gravitation that would otherwise cause the cloud to collapse is balanced by the outward pressure within the cloud due to motion of the atoms and molecules that compose it. Star formation is normally caused within molecular clouds by a triggering event which locally disturbs this equilibrium, causing runaway local collapsing regions within the cloud. Such causes can be the collision of one cloud with another, or the shock-wave within the interstellar medium caused by a nearby supernova explosion.

Selected Nebulae[edit]

  1. Anellet Cloud
  2. Anundarluu, The
  3. Anterior Cloud
  4. Basilisk Nebula
  5. Block Nebula
  6. Bourne Cloud
  7. The Cauldron
  8. Coalsack Nebula
  9. Curtain Nebula
  10. Curtain Nebula, Lesser
  11. Dark Cloud
  12. Dark Nebula, The
  13. Deimos Cloud
  14. Demon's Eye Nebula
  15. Helix Nebula
  16. Holowon Cloud
  17. Hook Nebula
  18. Horsehead Nebula
  19. Magister Cloud
  20. Inferno Nebula
  21. Orion Nebula
  22. North American Nebula
  23. Pelican Nebula
  24. Phobos Cloud
  25. Rim Reach Nebula
  26. Shell Nebula, Greater
  27. Shell Nebula, Lesser
  28. Separe Cloud
  29. Shadow Cloud
  30. Spark Nebula
  31. Ulund Cloud, Great
  32. Ulund Cloud, Little
  33. Veil of The Rim
  34. Verant's Head Nebula
  35. Wisp Cloud

History & Background (Dossier)[edit]

No information yet available. Article section under development.

  • Known to early Terran astronomers
  • Known to Vilani science

Nebula Effects on Ships[edit]

Nebulae often interfere with sensors, especially commercial ship sensor suites. They can affect other ship equipment as well.

Nebula Size & Relative Location[edit]

Nebulae are typically measured in the following units:

Nebula Size & Relative Location
Size Typical Metrics Remarks
Astrographic Hex Parsec or AU These smaller nebulae are typically represented on a single astrographic hex.
Subsector Light-year or Deshi They are smaller nebulae by astronomic standards, but less than a subsector in size.
Sector Light-year or Deshi These are typical nebulae, often several subsectors in size. Some might be proto-galaxies, failed galaxies, or accreted star clusters... possibly the remants of a nova starburst.
Multi-Sector Light-year or Deshi These are truly massive nebulae, often several sectors in size.

References & Contributors (Sources)[edit]

62px-Information icon.svg.png This article is missing content for one or more detailed sections. Additional details are required to complete the article. You can help the Traveller Wiki by expanding it.

This article was copied or excerpted from the following copyrighted sources and used under license from Far Future Enterprises or by permission of the author.