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.
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.
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