The supermassive black hole at the center of the Milky Way galaxy, a key target for studying extreme gravity, stellar dynamics, and black hole spin.
Astronomers reporting in Nature have found S301, the Milky Way's fastest known star, on a tight, eccentric orbit around the black hole Sgr A*. Its passes come close enough for the black hole's rotation to bend its path, so the team sees the star as a route to measuring that spin.
Reality
Marina Cermeño's team estimates that neutrons decaying near Sgr A* could produce petaelectronvolt protons using energy from the black hole's spin. The gamma-ray and neutrino signals it predicts are too faint for today's detectors and will need upgraded HAWC and IceCube instruments.
Reality
Mayura Balakrishnan and colleagues separated three overlapping X-ray sources in Chandra data to make the first uncontaminated maps of Sgr A East. The cleaner signal gives a baseline for testing whether the remnant has heated the gas around the Milky Way's central black hole.
Reality
Rodrigo Silva's team at Coimbra counted 43% of the S-cluster stars as binaries, then ran 100,000 simulated pairs through the black hole's tides for a million years and finished at 38%, close enough to argue the stars were born where they orbit.
Reality
Stefan Gillessen's group pulled S301 out of Very Large Telescope monitoring begun in 2023, and its perihelion of twelve astronomical units sits close enough that frame dragging should register in the orbit after roughly another decade of tracking.
Reality
S301 skims Sagittarius A* at about 8 percent of light speed. That proximity gives the GRAVITY+ team a direct spin measurement inside ten years, instead of decades of indirect modelling.
Perspective Coverage
5 publishersReality
JWST spectra of the star IRS 3 show silicate dust and water surviving near Sagittarius A*, and reclassify the star as oxygen-rich rather than carbon-rich.
Reality