Scientists say Sagittarius A supermassive black hole at centre of Milky Way poses no threat to Earth

Experts say the supermassive black hole at the centre of our galaxy poses no threat to us.

On Thursday, scientists provided the first look at the "gentle giant" lurking at the centre of the Milky Way.

Known as Sagittarius A* or Sgr A*, it possesses 4 million times the mass of our sun and is located about 26,000 light-years from Earth.

Auckland University's head of physics associate Professor Jan Eldridge spoke with Newshub Late on Friday night and said we have nothing to worry about.

"It's not producing much energy and the models that they've got of the black hole tend to suggest that they can't make one that is this low power so it is interesting that our black hole is quite a safe, gentle black hole."

Prof Eldridge told Newshub Late Sagittarius A is not pointing towards the Earth and is 30 degrees off to the side.

The black hole is the second one ever to be imaged and was obtained using the Event Horizon Telescope (EHT) international collaboration's global network of observatories working collectively to observe radio sources associated with black holes.

It showed a ring of light - super-heated disrupted matter and radiation circling at the tremendous speed at the edge of the event horizon - around a region of darkness representing the actual black hole. This is called the black hole's shadow or silhouette.

Imaging it was complicated by its dynamic environment including swirling gas around it.

Like most scientists, Prof Eldridge is fascinated by the image and said it's something they never thought we'd have.

"To have an image, to see the materials swirling around the black hole and the shadow within which is where the event horizon, in some extent space-time end, because once you go beyond that shadow you can never come back," Prof Eldridge told Newshub Late.

Harvard-Smithsonian Center for Astrophysics astrophysicist Michael Johnson has called Sagittarius A* "ravenous but inefficient," currently eating relatively little matter.

"If Sgr A* were a person, it would consume a single grain of rice every million years," Johnson said. It is putting out only a few hundred times the energy of the sun despite being much more massive.