A tag is a keyword or label that categorizes your question with other, similar questions. Using the right tags makes it easier for others to find and answer your question.

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a star with an enormous mass and luminosity, showing signs of a very high rate of mass loss.
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is used for questions regarding the subject of taking photographs of the night sky using digital or film imaging systems as well as the development and processing of the images. Que…
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Questions regarding two objects colliding into each other with considerable force.
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Questions about the chances of collisions between two objects or groups of objects, based on factors such as velocity, mass and number density.
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Inclination defines the angle between the plane of the orbit of a planet or comet and another plane, usually that of the ecliptic.
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Questions about a mathematical distribution explaining how common different masses of stars are.
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Questions regarding the space or objects outside of galaxies.
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Questions about the gas that lays between stars in galaxies.
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Questions about spacecraft journeying to other stellar systems.
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Questions about the German astronomer famous for his three laws of planetary motion. Do not use this tag for questions about the Kepler spacecraft.
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Questions regarding Jupiter, the 5th and largest planet in Earth's solar system.
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Questions related to Kuiper Belt Objects that exist in an annulus from 30AU to approximately 50AU from the Earth's Sun.
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Questions about the NASA space observatory famous for finding potentially habitable exoplanets. Do not use this tag for questions about Johannes Kepler.
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a disk-shaped belt of icy debris orbiting in the outer solar system, lying beyond the orbit of Neptune and extending to a distance of about 50 astronomical units, containing thousan…
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Questions on any of the 5 locations where a small object can maintain a stable orbital configuration with respect to two co-orbiting larger bodies.
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Late Heavy Bombardment; occurring between 3.7-4 billion years ago when the inner solar system underwent heavy asteroidal impacts. Also know as the Lunar Cataclysm.
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Questions regarding life in the universe, especially the possibility of life outside our planet, or the influence of astronomical forces on life on Earth.
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Questions regarding electromagnetic radiation in the visible spectrum.
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Questions regarding undesired brightening of the night sky inhibiting observation of astronomical objects.
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the group of galaxies that includes the Milky Way among others.
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Questions regarding the brightness of an object.
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Questions regarding an event where the Earth goes between the Sun and the Moon and casts a shadow on the Moon.
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the Andromeda Galaxy. A spiral galaxy and the largest member of the local group of galaxies. M31 is currently about 2.2 million light years from the Milky Way, but is approaching and is expecte…
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Questions regarding magnetic fields.