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 regarding one of the two main angles(coordinates) of an object perceived by an observer on Earth.
Questions about the water molecule (composed of two atoms of hydrodgen and one atom of oxygen) and its detection in celestial objects.
Questions about quasi-stellar radio sources, active galactic nuclei that are far away and quite old.
Questions about the "Goldilocks Zone" around a parent star where conditions are just right for the potential of life developing.
Questions regarding objects whose orbits bring them in close proximity to Earth, posing potential hazard.
Questions regarding two objects colliding into each other with considerable force.
Questions regarding the process of assigning an identifying set of characters to an astronomical object.
Questions about reflecting telescopes using a concave primary mirror and a flat diagonal secondary mirror.
Questions about observations performed without the aid of any optical instrument.
Questions regarding the inner portion of a galaxy; in the Milky Way, this is the area around Sagittarius A*.
Questions regarding disks of gas, dust, and plasma around a central object, such as a black hole, which takes in the matter.
like stars but never achieve nuclear fusion because they are too low-mass.
Questions about planets that do not orbit around a star. These planets travel through space.
Questions about streams of plasma released from the Sun or other stars (stellar winds).
Questions regarding structures designed to aid in the observation of astronomical objects.
Questions regarding the large "cloud" of small bodies that forms a sphere around the solar system.
Questions regarding Neptune, the 8th and furthest major planet orbiting Earth's sun.
Questions regarding the theory of gravity as proposed by Newton, in which the force of gravity depends only on the mass of bodies, a constant, and the distance between them, and depends on one equatio…
Questions regarding the large-scale change of orbits over time, as in the Nice Model.
For questions about objects or phenomena outside Earth, generally on other planets.
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 bodies smaller than planets but larger than other bodies, that do not meet at least one of the IAU's criteria for being a planet.
Questions about the outermost layer of a body.