Thursday, February 20, 2025

MASSIVE BLACK HOLE

Sagittarius A* is the supermassive black hole at the center of our home Milky Way galaxy.

It has a mass equal to billions of suns and has an accretion disk made up of gas and dust surrounding it.

Accretion disks are also the main light source from a black hole.

At only 26,000 light years away from Earth, Sagittarius A* is one of the few black holes that scientists can observe to watch the flow of gas and dust in its accretion disk.

Astrophysicists surprised by light show around the Milky Way’s supermassive black hole

Sagittarius A* has everything. Faint flickers, bright eruptions, and more.

By Laura Baisas

Posted Yesterday

a large orange circle surrounded by a blue square

Using NASA's James Webb Space Telescope, Northwestern astrophysicists gained the longest, most detailed glimpse yet of the supermassive black hole at the center of the Milky Way. They found the black hole's accretion disk emits a constant stream of flares with no periods of rest.

This video shows the 2.1 micron data taken on April 7, 2024. Farhad Yusef-Zadeh/Northwestern University

In the new study, the team used JWST’s near infrared camera (NIRCam). This instrument can simultaneously observe two infrared colors for long periods of time. They observed Sagittarius A* with their NIRCam for a total of 48 hours, using 8-to-10-hour increments across one Earth year. This allowed them to track how the black hole changed over time, similar to a time-lapse video.

Using NASA’s James Webb Space Telescope, Northwestern astrophysicists gained the longest, most detailed glimpse yet of the supermassive black hole at the center of the Milky Way. They found the black hole’s accretion disk emits a constant stream of flares with no periods of rest. This video shows the 2.1 micron data taken on April 7, 2024. CREDIT: Farhad Yusef-Zadeh/Northwestern University.

While flares were expected, Sagittarius A* was more active than would be anticipated. The team saw “ongoing fireworks” of various brightness and durations. About five to six big flares with several smaller sub-flares in between spewed out of the accretion disk.