Scientists see 'boom' at Milky Way's center with world's most powerful space telescope

The world's most powerful space telescope, the James Webb Space Telescope, has turned its sensitive instruments on the center of the Milky Way galaxy and the supermassive black hole located there called Sagittarius A*.

Most celestial objects are gravitationally bound in one way or another to Sagittarius A*, the supermassive black hole located at the center of our Milky Way galaxy. To put in perspective the sheer size of Sagittarius A*, researchers estimate you could fit 4.1 million Suns in the supermassive black hole in terms of total mass, and if you lined Suns side by side, about 17 Suns could fit across the event horizon. It's fair to say it's big. Sagittarius A* is about 26,000 light-years away from Earth, and researchers decided to point Webb at it to observe its chaotic impact on the surrounding space.

In a new paper published in The Astrophysical Journal Letters, researchers write Webb's observations revealed incredible flares of light ejecting out from the supermassive black hole. These observations from Webb mark the most detailed look researchers have been able to make around the Milky Way's central black hole, and according to the study, these flares of light are coming from the inner edge of the accretion disk, which is a disklike flow of gas, plasma, dust, or particles around any astronomical object, and in this case Sagittarius A*.

"In our data, we saw constantly changing, bubbling brightness. And then boom! A big burst of brightness suddenly popped up. Then, it calmed down again. We couldn't find a pattern in this activity. It appears to be random. The activity profile of this black hole was new and exciting every time that we looked at it," said lead study author Farhad Yusef-Zadeh, a professor of physics and astronomy at Northwestern University's Weinberg College of Arts and Sciences

What causes these flares? As material gets caught in the intense gravitational pull of the supermassive black hole, it begins to swirl around the black hole, forming an accretion disk. As the material is being rotated around the black hole, it's gaining speed and being heated up, and in the case of these flares, researchers believe the randomness of the flares can be attributed to new material colliding with the already superheated accretion disk. The collision results in a hot, energetic gas called plasma being expelled, resulting in a flash of radiation that Webb is observing.

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As for the longer, bigger flares, researchers propose the origins of these are due to magnetic reconnection events, which is a phenomenon that occurs when two different magnetic fields collide near the black hole and release energy particles near the speed of light. Webb's instruments were able to observe the black hole in two different wavelengths of light, a short and long wavelength. According to the researchers, these observations may lead to a deeper understanding of the mysterious physics occurring in the environment around the supermassive black hole.