Discover published sets by community

A standard unit of mass in astronomy equal to the mass of the Sun, approximately 1.989 x 10^30 kilograms. It is used to express the mass of other stars and galaxies.

A unit of length approximately equal to the mean Earth-Sun distance (about 150 million kilometers or 93 million miles). It is commonly used to measure distances within our solar system.

A measure of the intrinsic brightness of an astronomical object without the limitation of the spectral range; it integrates the energy emitted over all wavelengths.

A measure of the change in the wavelength of light or other electromagnetic radiation emitted by an object due to the Doppler effect caused by the object moving away from the observer.

A unit of distance used in astronomy to measure large distances to astronomical objects outside the solar system, equal to about 3.26 light-years or 31 trillion kilometers (19 trillion miles). It is derived from the parallax of one arcsecond.

A value used to describe the rate of expansion of the universe. Currently estimated at about 70 kilometers per second per megaparsec (km/s/Mpc), though the exact value is still debated.

The distance light travels in one year, commonly used to measure distances between stars and galaxies. It is approximately 9.46 trillion kilometers (5.88 trillion miles).

A unit of measurement used to describe the size of stars in comparison to the Sun. One Solar Radius is equal to the current radius of the Sun, which is about 696,340 kilometers (432,685 miles).

A non-SI unit of spectral flux density used in radio astronomy, equal to $10^{-26}$ watts per square meter per hertz. Named after the radio astronomer Karl Jansky.