Lightest black hole or heaviest neutron star? This object 40,000 light years away could be either

Scientists have discovered a new cosmic object that is surprisingly lighter than the smallest black hole and more massive than the heaviest neutron star. The mysterious object was spotted in our Milky Way galaxy, which was found at a site 40,000 light years away from Earth.

The discovery has baffled astronomers who are studying the differentiation between a neutron star and a black hole, both of which are born when a massive star dies.

The object was first detected inside a dense globule of stars named NGC 1851, using the MeerKAT Radio Telescope. The findings of the new cosmic object were published on January 18 in the journal Science.

Add WION as a Preferred Source

Also Read |Mars equator hiding giant slabs of ice with enough water to cover the entire planet

Newly found cosmic object falls within a neutron star and a black hole

Researchers suggest that the new object falls within the historical “mass gap” between black holes and neutron stars. This means it can be either of the one.

"Either possibility for the nature of the companion is exciting," lead author Ben Stappers, a professor of astrophysics at The University of Manchester in the UK, said in a statement.

"A pulsar-black hole system will be an important target for testing theories of gravity and a heavy neutron star will provide new insights in nuclear physics at very high densities."

Also Read |Can pig livers help humans with liver failure? THIS experiment raises hopes for animal-to-human transplants

Both black holes and neutron stars are corpses of massive dead stars that die in violent explosions called supernovas.

Though both are born in the same way, these objects are poles apart when it comes to their internal wiring and masses. But the lightest black hole and the heaviest neutron star can look similar from far away, which is why scientists have yet to declare their verdict.

For most of astronomy's history, scientists could only spot neutron stars as heavy as twice the mass of the sun and black holes as light as five solar masses, leaving everything in between a mystery.

The gap between the two, known as the mass gap, was finally crossed in 2019 when the Laser Interferometer Gravitational-Wave Observatory (LIGO) detected space-time ripples indicative of a light black hole or heavy neutron star falling somewhere between the two.

Also Read |Astrobotic loses contact with Peregrine lunar lander

What the object could be a massive neutron star the lightest black hole, or maybe some other exotic star husk, is still unclear. The researchers are still probing what could help uncover this mystery.

"Uncovering the true nature of the companion will be a turning point in our understanding of neutron stars, black holes, and whatever else might be lurking in the black hole mass gap", said co-author Arunima Dutta, a doctoral student at the Max Planck Institute for Radio Astronomy in Bonn, Germany.

(With inputs from agencies)