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 process of inspecting, cleaning, transforming, and modeling data with the goal of discovering useful information, suggesting conclusions, and supporting decision making.
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Questions regarding the most massive examples of black holes that typically reside at the centers of galaxies.
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Icy bodies that usually consist of methane, water, and other materials that originate from beyond the jovian planets, and occasionally fall into the inner solar system giving off a massive tail as mat…
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Questions related to the phenomenon whereby electromagnetic radiation (such as visible light) generated by an object moving away from an observer will have increased in wavelength (i.e. shifted toward…
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Questions regarding the history of astronomy, including discoveries and scientists.
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Questions about the complete or partial blocking of the sun by the moon.
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Waves in spacetime formed by the acceleration of massive bodies. A passing wave causes spacetime to be stretched and squashed by a very small amount. Typically we can only detect the most energic grav…
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Questions about the measurement of light waves whereby the wavelength is classified by its position in the electromagnetic spectrum.
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Questions about the source or effects of the matter that makes up 85% of the matter in the universe but appears to only interact gravitationally.
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The application of ballistics and celestial mechanics to the practical problems concerning the motion of rockets and other spacecraft.
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Questions regarding the property of astronomical objects that determines their inertial resistance and gravitational interaction with other bodies.
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Questions related to the evolution of stars.
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Questions regarding a degenerate star that is mainly composed of neutrons.
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Questions on time, the indefinite progress of events in the Universe.
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Questions related to the physical processes involved in or to the observations of the process of forming a star.
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a measurement of the average kinetic energy of the molecules in an object or system. In simpler words: it's the degree or intensity of heat present in a substance or object that is comm…
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gravitationally linked and orbit around their barycenter.
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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 about the parameters needed to specify the characteristics of an orbit.
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Questions about positions of objects in the sky, either relative to a fixed coordinate system like the equatorial and ecliptic coordinate systems, or relative to an observer's point of view.
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Questions about the observed frequency range of the electromagnetic radiation of a celestrial object.
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Questions regarding magnetic fields.
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Questions regarding massive planets composed of layers of gases, such as hydrogen and helium, surrounding a solid/liquid core.
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Questions about the processes, theories and evidence for the formation of planetary bodies.
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Questions regarding the region of space containing all the objects that we can detect using any method of observation.
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Questions regarding the planet Venus, the second planet from Earth's sun.
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Questions on objects passing through the atmosphere which leave visible wakes of incandescent material.
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Questions regarding the Hubble Space Telescope, a visible light telescope orbiting Earth.
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Questions regarding the phenomenon in the early universe characterized by an extreme expansion of space.
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Questions about Saturn, the sixth planet from the Sun.
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Questions regarding the amount of energy produced by an object per unit of time.
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Behaviour and properties of light, and its interaction with matter, particularly in detection of light.
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Questions regarding the as-yet-unknown energy permeating the universe that is responsible for its expansion.
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Questions regarding an object's movement, or its distance traveled relative to the time taken.
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Questions regarding specific terms, names, or naming conventions.
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Questions regarding two or more stars gravitationally bound to each other