S2 and the S-stars

stars orbiting the black hole · proof it exists

26,670 light-years from Earth

Tracking these stars for 30 years proved Sgr A* is a black hole (Nobel Prize 2020). S2 swings within 120 AU of it every 16 years, reaching 2.5% of light speed.

• S2: 16-year orbit shown in 20 seconds
• at closest approach 7,650 km/s; its light is visibly reddened by gravity

kind

star

with

Sagittarius A*