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*.

In 2026, S301 was reported as the closest and fastest securely observed star orbiting Sgr A*.https://www.eso.org/public/news/eso2612/ It approaches to about 12 AU from the black hole and reaches approximately 8.5% of the speed of light at pericentre. The previous record holder was S4714.

List of stars The inferred orbits of stars around the supermassive black hole Sagittarius A* at the Milky Way's center are according to Gillessen et al. 2017, with the exception of S2 which is from GRAVITY 2019, and S4711 up to S4715, which are also from Peißker et al., Aug 2020. Data for S62, reported in Peißker et al. Jan 2020, was later found to be further than expected from Sagittarius A* and is now thought to be due to a mistaken observation of S29. Data for S301 are from Abd El Dayem et al. (2026); because its radial velocity has not yet been measured, two possible orbital orientations remain, and the first solution reported in the study is used here.

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, and Δ indicates the standard deviation of the associated quantities.

Binary Star system D9 was recently found in the S Cluster.

id1 id2 Other nameSpectral classMass (Solar masses)Temperature (K) a Δa e Δe i (°) Δi Ω (°) ΔΩ ω (°) Δω Tp (yr) ΔTp P (yr) ΔP Kmag q (AU) Δq v (%c) ΔvRadius (Solar radii) S1 S0-1B0-2 V 0.5950 0.0240 0.5560 0.0180 119.14 0.21 342.04 0.32 122.30 1.40 2001.800 0.150 166.0 5.8 14.70 2160.7 6.7 0.55 0.034.49 S2 S0-2B0-2 V14 0.1251 0.0001 0.8843 0.0001 133.91 0.05 228.07 0.04 66.25 0.04 2018.379 0.001 16.0518 0.0 13.95 118.4 0.2 2.56 0.006.36 S4S0-3B0-2 V 0.3570 0.0037 0.3905 0.0059 80.33 0.08 258.84 0.07 290.80 1.50 1957.400 1.200 77.0 1.0 14.40 1779.7 25.1 0.57 0.01 S6S0-7B0-2 V 0.6574 0.0006 0.8400 0.0003 87.24 0.06 85.07 0.12 116.23 0.07 2108.610 0.030 192.0 0.2 15.40 860.3 4.4 0.94 0.004.53 S8 S0-4B0-2 V 0.4047 0.0014 0.8031 0.0075 74.37 0.30 315.43 0.19 346.70 0.41 1983.640 0.240 92.9 0.4 14.50 651.7 22.5 1.07 0.014.47 S9S0-5B0-2 V 0.2724 0.0041 0.6440 0.0200 82.41 0.24 156.60 0.10 150.60 1.00 1976.710 0.920 51.3 0.7 15.10 793.2 36.9 0.93 0.02S10S0-6[CRG2004] 12K5 III14.26 S12 S0-19B4-9 V 0.2987 0.0018 0.8883 0.0017 33.56 0.49 230.10 1.80 317.90 1.50 1995.590 0.040 58.9 0.2 15.50 272.9 2.0 1.69 0.01 S13 S0-20B4-9 V 0.2641 0.0016 0.4250 0.0023 24.70 0.48 74.50 1.70 245.20 2.40 2004.860 0.040 49.0 0.1 15.80 1242.0 2.4 0.69 0.01 S14 S0-16B4-9 V 0.2863 0.0036 0.9761 0.0037 100.59 0.87 226.38 0.64 334.59 0.87 2000.120 0.060 55.3 0.5 15.70 56.0 3.8 3.83 0.063.1789 S17K0 III5,000 0.3559 0.0096 0.3970 0.0110 96.83 0.11 191.62 0.21 326.00 1.90 1991.190 0.410 76.6 1.0 15.30 1755.3 16.4 0.57 0.029 S18S0-18 0.2379 0.0015 0.4710 0.0120 110.67 0.18 49.11 0.18 349.46 0.66 1993.860 0.160 41.9 0.2 16.70 1029.3 3.8 0.77 0.01 S19S0-28K-M 0.5200 0.0940 0.7500 0.0430 71.96 0.35 344.60 0.62 155.20 2.30 2005.390 0.160 135.0 14.0 16.00 1063.3 4.5 0.83 0.20 S21 0.2190 0.0017 0.7640 0.0140 58.80 1.00 259.64 0.62 166.40 1.10 2027.400 0.170 37.0 0.3 16.90 422.7 3.6 1.32 0.02 S22 1.3100 0.2800 0.4490 0.0880 105.76 0.95 291.70 1.40 95.00 20.00 1996.900 10.200 540.0 63.0 16.60 5903.7 9.7 0.32 0.10 S23 0.2530 0.0120 0.5600 0.1400 48.00 7.10 249.00 13.00 39.00 6.70 2024.700 3.700 45.8 1.6 17.80 910.5 1.6 0.85 0.06 S24S0-26 0.9440 0.0480 0.8970 0.0049 103.67 0.42 7.93 0.37 290.00 15.00 2024.500 0.030 331.0 16.0 15.60 795.3 30.8 0.99 0.07S27S0-27K3 III15.74 S29 0.4280 0.0190 0.7280 0.0520 105.80 1.70 161.96 0.80 346.50 5.90 2025.960 0.940 101.0 2.0 16.70 952.2 67.4 0.87 0.05 S31S0-8B4-9 V 0.4490 0.0100 0.5497 0.0025 109.03 0.27 137.16 0.30 308.00 3.00 2018.070 0.140 108.0 1.2 15.70 1653.7 14.6 0.63 0.02 S33S0-33 0.6570 0.0260 0.6080 0.0640 60.50 2.50 100.10 5.50 303.70 1.60 1928.000 12.000 192.0 5.2 16.00 2106.5 179.7 0.56 0.03 S38S0-38M III5.97133,330 0.1416 0.0002 0.8201 0.0007 171.10 2.10 101.06 0.24 17.99 0.25 2003.190 0.010 19.2 0.0 17.00 208.4 1.5 1.91 0.01185.84 S39 0.3700 0.0150 0.9236 0.0021 89.36 0.73 159.03 0.10 23.30 3.80 2000.060 0.060 81.1 1.5 16.80 231.2 3.3 1.86 0.09 S42 0.9500 0.1800 0.5670 0.0830 67.16 0.66 196.14 0.75 35.80 3.20 2008.240 0.750 335.0 58.0 17.50 3364.4 24.8 0.44 0.13 S54 1.2000 0.8700 0.8930 0.0780 62.20 1.40 288.35 0.70 140.80 2.30 2004.460 0.070 477.0 199.0 17.50 1050.2 1.9 0.86 0.78 S55 S0-102B0-2 V 0.1078 0.0010 0.7209 0.0077 150.10 2.20 325.50 4.00 331.50 3.90 2009.340 0.040 12.8 0.1 17.50 246.1 4.1 1.70 0.02 S60 0.3877 0.0070 0.7179 0.0051 126.87 0.30 170.54 0.85 29.37 0.29 2023.890 0.090 87.1 1.4 16.30 894.5 1.7 0.89 0.02 S66S1-2[RGH2007] GEN-0.06-1.01O-B 1.5020 0.0950 0.1280 0.0430 128.50 1.60 92.30 3.20 134.00 17.00 1771.000 38.000 664.0 37.0 14.80 10712.4 620.5 0.21 0.02 S67S1-3O-B 1.1260 0.0260 0.2930 0.0570 136.00 1.10 96.50 6.40 213.50 1.60 1705.000 22.000 431.0 10.0 12.10 6511.2 360.6 0.29 0.01 S71S0-71 0.9730 0.0400 0.8990 0.0130 74.00 1.30 35.16 0.86 337.80 4.90 1695.000 21.000 346.0 11.0 16.10 803.8 1.4 0.99 0.06 S83S0-15[GEO97] W5O9-9.5 V33,000 1.4900 0.1900 0.3650 0.0750 127.20 1.40 87.70 1.20 203.60 6.00 2046.800 6.300 656.0 69.0 13.60 7738.6 22.5 0.27 0.057.5 S85M0 III9.1783,800 4.6000 3.3000 0.7800 0.1500 84.78 0.29 107.36 0.43 156.30 6.80 1930.200 9.800 3580.0 2550.0 15.60 8277.1 29.6 0.30 0.3351.008 S87S1-12 2.7400 0.1600 0.2240 0.0270 119.54 0.87 106.32 0.99 336.10 7.70 611.000 154.000 1640.0 105.0 13.60 17390.5 2572.9 0.17 0.02 S89 1.0810 0.0550 0.6390 0.0380 87.61 0.16 238.99 0.18 126.40 4.00 1783.000 26.000 406.0 27.0 15.30 3191.8 407.2 0.46 0.04 S91 1.9170 0.0890 0.3030 0.0340 114.49 0.32 105.35 0.74 356.40 1.60 1108.000 69.000 958.0 50.0 12.20 10928.4 74.5 0.22 0.02 S96S0-96GCIRS 16COfpe/WN9 1.4990 0.0570 0.1740 0.0220 126.36 0.96 115.66 0.59 233.60 2.40 1646.000 16.000 662.0 29.0 10.00 10127.0 530.0 0.22 0.02 S97 AS1-16GCIRS 16SWOfpe/WN95024,400 2.3200 0.4600 0.3500 0.1100 113.00 1.30 113.20 1.40 28.00 14.00 2132.000 29.000 1270.0 309.0 10.30 12333.9 305.9 0.21 0.0854.5 × 58.2 × 62.7S97 B5023,50054.5 × 58.2 × 62.7 S145M III5.12163,330 1.1200 0.1800 0.5000 0.2500 83.70 1.60 263.92 0.94 185.00 16.00 1808.000 58.000 426.0 71.0 17.50 4580.2 1471.2 0.37 0.10179.46 S175 0.4140 0.0390 0.9867 0.0018 88.53 0.60 326.83 0.78 68.52 0.40 2009.510 0.010 96.2 5.0 17.50 45.0 0.8 4.27 0.47 S3011.1–1.5 0.0830 0.0007 0.9832 0.0010 124.09 1.10 73.8 3.5 293.4 2.2 2023.126 0.010 8.68 0.11 19.3 11.5 8.51.4–1.6 S4711B8-9 V2.211,587.84 0.0751 0.0015 0.768 0.030 114.71 2.92 20.10 3.72 131.59 3.09 2010.85 0.06 7.6 0.3 18.4 143.7 7.4 2.2 0.22.59 S4712B9-A0 V2.210,0000.451 0.0025 0.365 0.032 117.28 1.31 166.38 3.20 238.08 3.43 2007.12 0.08 112.0 2.9 18.4 2366 120 0.48 0.02 S47132.1 0.2 0.095 0.351 0.059 111.07 1.66 95.06 5.15 301.97 8.02 2000.03 0.22 33.2 2.5 18.5 1073 110 0.71 0.05 S47142 0.102 0.0003 0.985 0.011 127.7 0.28 129.28 0.63 357.25 0.08 2017.29 0.02 12.0 0.3 17.7 12.6 9.3 8.0 3 S4715B9 V2.8 0.1439 0.011 0.247 0.040 129.8 3.72 282.15 2.92 359.99 5.38 2008.05 0.3 20.2 2.4 17.8 894 83 0.75 0.042.37S4716B7-8 V12,417.071.93000.756161.24151.540.0734.02.45 R34 1.8100 0.1500 0.6410 0.0980 136.00 8.30 330.00 19.00 57.00 8.00 1522.000 52.000 877.0 83.0 14.00 5314.6 856.3 0.36 0.05 R44 3.9000 1.4000 0.2700 0.2700 131.00 5.20 80.50 7.10 217.00 24.00 1963.000 85.000 2730.0 1350.0 14.00 23285.6 901.5 0.15 0.11 id1 id2 a Δa e Δe i (°) Δi Ω (°) ΔΩ ω (°) Δω Tp (yr) ΔTp P (yr) ΔP Kmag q (AU) Δq v (%c) Δv

References