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.
Questions about the space observatory GAIA.
A sky-survey is a general map or image of a region of the sky which lacks a specific observational target, but this tag also applies to surveys of a given class of objects, (e.g. TESS)
Questions about planets that do not orbit around a star. These planets travel through space.
Questions about reflecting telescopes using a concave primary mirror and a flat diagonal secondary mirror.
Questions related to processes and principles related to the interior and the solid surface of a planetary body.
Questions regarding lists of star designations.
Questions about the chemical reactions that occur on celestial bodies, in the interstellar medium, and in other astronomical environments.
Questions regarding the second ordinate of the equatorial celestial system.
Questions about the simplest and most abundant element in the Universe.
Questions about the dynamical processes leading to the assembling of a celestial object.
Questions regarding the National Aeronautics and Space Administration, the American civilian space agency.
Questions regarding the large-scale change of orbits over time, as in the Nice Model.
Questions about red giants, large luminous low-mass stars in a late phase of stellar evolution.
Questions regarding the inner portion of a galaxy; in the Milky Way, this is the area around Sagittarius A*.
Questions targeting the exact (possibly mathematical) description of a phenomena or term.
Questions about the temporal duration of a celestrial object.
Questions regarding undesired brightening of the night sky inhibiting observation of astronomical objects.
Questions regarding celestial bodies that are in hydrostatic equilibrium (spheroidal) and orbit the Sun directly, but do not fulfill the IAU's criterion of "clearing" their neighbourhood of planetesim…
Questions regarding casually watching the stars.
Questions related to Astropy, a community Python package for Astronomy
Questions about the "adulthood" of stars. The main sequence is a distinctive band of stars that appears in a color-magnitude plot (known as Hertzsprung-Russell diagram). Stars appear in the main seque…
Questions about the origins of life on Earth, and the existence and detection of extraterrestrial life.
Questions regarding a type of elementary particle with 0 mass and is a quantum of the electromagnetic field. Photons always travel at constant speed in a vacuum.
Questions regarding a sudden brightness increase due to the release of magnetic energy from the sun.
For questions about objects or phenomena outside Earth, generally on other planets.
Questions about the circumstellar disk orbiting in the outer Solar System, beyond the orbit of Neptune.
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.
Questions which are asking about the mathematical formulations whose theoretical and numerical analysis provides insight, answers, and guidance useful for the originating application.
Questions about primary, unprocessed measurements and about where to find them.
Questions about the time-dependence of the light intensity of a celestial object or region.
Questions about the branch of astronomy that studies the regularities in the motions of stars in gravitational fields of stellar systems, as well as the evolution of stellar systems.
Questions regarding grouping objects together based on one or more shared property.
Questions regarding the material at or near the center of an astronomical object.
Questions regarding Uranus, the 7th planet from Earth's sun.