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Atmospheres of planets, moons, and other solar system bodies excluding stars. For those, use "stellar-atmosphere" instead. For influences of Earth's atmosphere on astronomical observations use "atmosp…
Questions related to the evolution of stars.
Questions about the increase with time of distance between two distant points in the Universe.
The near-vacuum extending between the planets and stars, containing small amounts of gas and dust. Also called outer space to refer to the physical universe beyond the Earth's atmosphere.
Questions regarding the currently prevalent cosmological model for the origin of the universe.
Questions related to the phenomenon whereby electromagnetic radiation (such as visible light) generated by an object moving away from an observer will have increase in wavelength (i.e. shifted toward …
Questions regarding the most massive examples of black holes that typically reside at the centers of galaxies.
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.
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…
Questions on time, the indefinite progress of events in the Universe.
Questions regarding a degenerate star that is mainly composed of neutrons.
Questions regarding a pair of stars that are gravitationally bound and orbit around their barycenter.
Questions regarding the property of astronomical objects that determines their inertial resistance and gravitational interaction with other bodies.
Questions involving reference frames, time scales, and how they are determined. Not for general Astronomy 101 questions.
Questions about the complete or partial blocking of the sun by the moon.
Questions about the observed frequency range of the electromagnetic radiation of a celestial object.
Temperature is 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…
Questions about the parameters needed to specify the characteristics of an orbit.
Questions related to the physical processes involved in or to the observations of the process of forming a star.
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.
Behaviour and properties of light, and its interaction with matter, particularly in detection of light.
Questions about the processes, theories and evidence for the formation of planetary bodies.
Questions regarding specific terms, names, or naming conventions.
Questions about using the Python programming language to solve astronomical problems. General questions about Python are off-topic but might be asked on Stack Overflow.
For astronomy questions with a heavy mathematical component, more than simple formulas. For regular mathematics question, visit our sister site Mathematics Stack Exchange.
Questions regarding magnetic fields.
Questions regarding the region of space containing all the objects that we can detect using any method of observation.
Questions about inducing chemistry, physics, and many more branches of science into astronomy.
Questions regarding the planet Venus, the second planet from the Sun.
Questions regarding the motions of celestial objects.
Questions regarding the measurement of the amount of light coming from astronomical objects.
Questions about the apparent force stretching a body towards and away from the center of mass of another body due to the variance in acceleration due to gravity
Questions regarding massive planets composed of layers of gases, such as hydrogen and helium, surrounding a solid/liquid core.
Questions regarding telescopes in orbit around Earth, such as the Hubble Space Telescope.
Questions regarding the Hubble Space Telescope, a visible light telescope orbiting Earth.
Questions regarding the amount of energy produced by an object per unit of time.