The Sagittarius A* cluster is the cluster of stars in close orbit around Sagittarius A*, the supermassive black hole at the center of the Milky Way (in the Galactic Center). The individual stars are often listed as "S-stars", but their names and IDs are not formalized, and stars can have different numbers in different catalogues.

One of the most studied stars is S2, a relatively bright star that also passes close by Sgr A*.

As of 2020^[update], S4714 is the current record holder of closest approach to Sagittarius A*, at about 12.6 astronomical units (1.88×10⁹ km), almost as close as Saturn gets to the Sun, traveling at about 8% of the speed of light. These figures given are approximate, the formal uncertainties being 12.6±9.3 au and 23928±8840 km/s. Its orbital period is 12 years, but an extreme eccentricity of 0.985 gives it the close approach and high velocity.^[2]

The inferred orbits of stars around supermassive black hole candidate Sagittarius A* at the Milky Way's center are according to Gillessen et al. 2017,^[3] with the exception of S2 which is from GRAVITY 2019,^[4] S62 which is from Peißker et al. Jan 2020,^[5] and S4711 up to S4715, which are also from Peißker et al., Aug 2020.^[2]

Here id1 is the star's name in the Gillessen catalog and id2 in the catalog of the University of California, Los Angeles. a, e, i, Ω and ω are standard orbital elements, with a measured in arcseconds. Tp is the epoch of pericenter passage, P is the orbital period in years and Kmag is the K-band apparent magnitude of the star. q and v are the pericenter distance in AU and pericenter speed in percent of the speed of light,^[6] and Δ indicates the standard deviation of the associated quantities.