Astronomers discover the largest black hole in the Milky Way: it is 33 times larger than the Sun

Astronomers have discovered a huge black hole that was formed as a result of a star explosion just 2,000 light-years from Earth.

This was reported by SSPDaily.

BH3 is the most massive stellar black hole found in the Milky Way and was discovered by researchers due to the powerful attraction of a companion star orbiting the object in the constellation Aquila.

The unexpected discovery is so important that the scientists released details about the object earlier than planned to allow other astronomers to make further observations as soon as possible.

"It's a complete surprise," said Dr. Pasquale Panuzzo, an astronomer and member of the Gaia group at the Paris Observatory. "This is the most massive stellar black hole in our galaxy and the second closest one detected so far."

Stellar black holes are formed when massive stars collapse at the end of their lives. Dozens of them have been discovered in the Milky Way, with most of them having a mass about 10 times that of the Sun.

The most stunning black hole in the Milky Way, Sagittarius A, has a total mass of several million suns. It is hidden in the heart of the galaxy and was formed not from the explosion of a star but as a result of the collapse of huge clouds of dust and gas.

The researchers discovered BH3 in the latest data set collected by the European Space Agency's Gaia mission. The space telescope was launched in 2013 to create a 3D map of a billion stars.

While analyzing Gaia's observations, the researchers noticed a clear wobble of one of the stars in the constellation Aquila, which is visible in the summer sky in the northern hemisphere. The movement indicated that the star was being pulled around by a black hole that is 33 times more massive than the Sun.

Subsequent observations with the European Southern Observatory's large telescope in the Chilean Atacama Desert confirmed BH3's mass and the star's orbit, which revolves around the black hole once every 11.6 years. "Only the central black hole of the Milky Way is more massive than this," Panuzzo said.

Although BH3 is more massive than other stellar black holes in the Milky Way, it is similar to some of those detected by gravitational waves, or ripples in space-time, that are generated by the collision of black holes in distant galaxies.

"We've only seen black holes of this mass with gravitational waves in distant galaxies," Panuzzo says. "This establishes a link between the stellar black holes we see in our galaxy and these gravitational wave discoveries."

There may be 100-meter stellar black holes in the Milky Way, but despite their enormous mass and the powerful forces they generate, they can be extremely difficult to detect. "Most of them don't have stars orbiting them, so they're almost invisible to us," Panuzzo said.

The measurements of the companion star BH3 showed no sign that it was contaminated with material that flew out of the stellar explosion that formed the black hole. This suggests that the black hole formed long before it captured the companion star in its powerful gravitational field.

The next tranche of Gaia data is not due to be published until late 2025, but the importance of the discovery has prompted the international team to release details about BH3 earlier so that astronomers can study it immediately.

"As soon as it's known, people will rush to observe it to see if there are any emissions from the black hole," Panuzzo said. "This will tell us about the wind that blows from stars like the one orbiting the black hole, as well as the physics of the black hole and how matter falls into it."

As a reminder, NASA is preparing to make an important announcement about Mars, namely what is happening with the Mars Sample Return program and what next steps will be taken. This is a mission to deliver samples of Martian rock to Earth.