Fastest Star in the Milky Way Discovered
LAKEPORT, Calif. – Astronomers have unveiled the fastest known star in our galaxy, orbiting the supermassive black hole at its center, Sagittarius A*.
Discovery of S301
- The star, designated S301, was detected with the European Southern Observatory’s Very Large Telescope Interferometer (VLTI) and reaches speeds of 25,000 km/s in its orbit around the black hole, which has four million times the mass of our Sun.
- S301 comes remarkably close to Sagittarius A*, at about 12 times the Earth-Sun distance, making it unique among known stars.
Orbital Dynamics and Significance
- S301 completes its orbit in just 8.7 years, traveling faster than 8% of the speed of light.
- During its close approach, S301 could be used for the first time to directly measure the rotation of a black hole, potentially confirming predictions made by Einstein’s general theory of relativity regarding spinning black holes.
Insights from Researchers
Nobel laureate Reinhard Genzel noted, “Decades of carefully tracking stars orbiting our galaxy’s central black hole have led to this breakthrough discovery.” Felix Mang, a PhD student involved in the research, emphasized the unprecedented close orbit of S301 and its implications for studying spacetime properties.
Observation Techniques
- Finding S301 was challenging, as it appears over two billion times fainter than Betelgeuse in the night sky.
- The VLTI’s capability to combine the light from four telescopes allowed astronomers to achieve high-resolution observations essential for tracking S301’s path.
Future Observations
Follow-up observations with both the upgraded GRAVITY+ instrument and the future Extremely Large Telescope (ELT) will be crucial for fully understanding S301’s orbit and potentially measuring Sagittarius A*’s spin within the next decade.
Conclusion
The discovery of S301 opens new avenues for exploring the dynamics of supermassive black holes and understanding fundamental aspects of physics in extreme environments.
