The supermassive black hole at the center of the Milky Way is the undisputed heavyweight champion of the Milky Way, but a newly discovered object has taken the crown as the most massive known stellar black hole in the Milky Way, with an impressive mass of 33 times the mass of the Milky Way. Our sun.
A team led by Pasquale Panuzzo, an astronomer at the Paris Observatory, has discovered the most massive stellar black hole ever discovered in the Milky Way. Gaia BH3 dwarfs the previous record holder, Cygnus X-1, which weighed only 21 solar masses.The research result is detailed In a paper published today in the journal Astronomy & Astrophysics.
Gaia BH3 is located in the constellation Aquila, about 2,000 light-years from Earth. The team discovered this while reviewing data from the European Space Agency’s Gaia mission. The Gaia mission is a space-based observatory operating since 2013. Gaia’s ongoing mission is to build the most detailed three-dimensional map of our galaxy. Astronomers already knew about this star orbiting BH3, but its status as a black hole companion was completely surprising, and the resulting heft was even more surprising.
“When I first saw the results, I was convinced there was something wrong with the data. I couldn’t believe it,” Panuzzo told Gizmodo. “Now, I feel like I really did it this The discovery of my life! “
The discovery was supported by a range of ground-based observatories and precision instruments, including the Ultraviolet and Visible Echelle Spectrograph (UVES) at the European Southern Observatory’s Very Large Telescope in Chile, the HERMES spectrograph at the Mercator Telescope in Spain, and the SOPHIE French high-precision spectrograph .
Astronomers use Gaia’s precise measurements to determine the size of the orbit and the time it takes for the star to orbit the black hole. They then applied Kepler’s laws, the principles that describe the motion of planets and stars, to calculate the black hole’s mass from the size and period of its orbit. They used two methods: astrometry, which tracks the slight wobbling motion of a companion star as it shifts position across the sky, and spectroscopy, which uses the Doppler effect to measure how quickly a star is moving closer or farther away. us.
Stellar black holes are the remnants of massive stars that collapsed under their own gravity, usually forming black holes with a mass of about 10 times the mass of the sun. According to the new study, Gaia BH3’s massive mass suggests it originated as a metal-poor star that retained more mass during its lifetime and therefore likely formed a larger black hole upon death.
In comparison, the supermassive black hole Sagittarius A* at the core of the Milky Way is much larger, with a mass of about 4 million times that of the Sun. Rather than forming from the collapse of individual stars, these behemoths may have formed from the merger of smaller black holes and the accumulation of gas and stellar material over millions of years.
Stellar black holes “are formed by the gravitational collapse of a massive star (one that may be 40 to 50 times the mass of the Sun) at the end of its life,” Panuzzo explained. “These types of stars have short lifespans of just a few million years compared to the Sun’s 10 billion years, and they end their lives as supernovae, leaving behind black holes. That’s why we call them ‘stellar’ black holes, so as not to associate them with Confusion with supermassive black holes at the center of galaxies.”
Panuzzo says it’s “very likely” there are larger stellar black holes in our galaxy. Previously, LIGO-Virgo-KAGRA Gravitational Telescope Detection of black hole mergers exceeding 80 solar masses in distant galaxies. In fact, supermassive stellar black holes have been detected before, but in other galaxies and using alternative detection methods.These distant black holes are caused by Gravitational wave astronomy, which observed the ripples in space-time caused by stellar-black hole mergers. I asked Panuzzo why we can find massive stellar black holes in distant galaxies, but only recently discovered one in our own galaxy.
“There are two reasons,” he said. “First, the LIGO-Virgo-KAGRA gravitational telescope is able to detect black hole mergers at great distances, detecting billions of galaxies. The second is that these black holes are produced by massive stars with low metallicity, that is, Stars are composed almost entirely of hydrogen and helium, with only trace amounts of other elements, Panuzzo said: “These stars only emerged in our galaxy’s infancy, so we never see new massive black holes forming in the galaxy. ”
The data used in the study were originally intended for the next Gaia data release, expected in late 2025. However, due to the significance of the discovery, the team chose to release the findings early. “This discovery has many implications for models of stellar evolution and gravitational wave fields,” Panuzzo explained. “It was felt that this particular discovery could not be hidden from the community for two years, waiting for the next release.” What’s more, he added, what’s more, now that it’s public, the scientific community can make follow-up observations much earlier.
To this end, future observations using the gravity instrument on the European Southern Observatory’s Very Large Telescope Interferometer will aim to determine whether this black hole is attracting material from its surroundings, providing a deeper understanding of its nature and behavior.
more: Ripples in space-time reveal mysterious object colliding with stellar corpse.