Stars · Star orbiting Sagittarius A*
S2
26,700 light-years · Light crosses it in 28 seconds
- Across
- 8.5 million km
- Vs Earth
- 6.1× Sun
- Mass
- 14 Suns
About
S2 is a hot young star orbiting Sagittarius A*, the black hole at the centre of the Milky Way. Following it around its 16-year orbit for three decades proved that something four million times the Sun's mass hides there, and won the 2020 Nobel Prize in Physics.
Races around the Milky Way's central black hole every 16 years.
At a glance
| Distance | 26,700 light-years |
|---|---|
| Orbit | 16 years |
| Closest approach | 120 times Earth–Sun |
| Top speed | 7,650 km/s |
Did you know
- In 2018 its light was stretched by the black hole's gravity exactly as Einstein predicted.
- Its whole orbit slowly turns with each lap, another effect of relativity, first measured in 2020.
- It is about 14 times the Sun's mass, yet it is whipped around like a pebble on a string.