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 circumstellar disk orbiting in the outer Solar System, beyond the orbit of Neptune.
Questions about the simplest and most abundant element in the Universe.
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 undesired brightening of the night sky inhibiting observation of astronomical objects.
Questions regarding the space or objects outside of galaxies.
Questions regarding matter in its gaseous state, and how it behaves in astronomy (e.g. forming stars in giant molecular clouds).
flashes of gamma rays, produced by extremely powerful explosions in distant galaxies. They are among the most powerful events in the universe
Questions about orbits with high eccentricities, which deviate greatly from perfect circles.
Questions about the apparent displacement of a celestial body with respect to its background when observed along two different lines of sight.
Questions about spacecraft journeying to other stellar systems.
Questions to do with how new atomic nuclei are created inside the universe.
Inclination defines the angle between the plane of the orbit of a planet or comet and another plane, usually that of the ecliptic.
Questions regarding atmospheric conditions on either Earth or on other planets.
Questions regarding thermal energy and its effect on astronomical objects.
Questions regarding the future and ultimate fate of the Universe, including the heat death, Big Freeze, Big Rip, or Big Crunch.
a planet that has a compact rocky surface like the Earth's; the four innermost planets in the solar system.
Questions related to earth processes or related processes and principles.
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 large, dense, massive collections of stars orbiting galaxies, thought to have formed in the early universe.