WEBVTT FILE

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Using NASA’s James Webb Space Telescope,

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a team of astrophysicists has gained the longest,  

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most detailed glimpse yet of the void

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that lurks in the middle of our galaxy.

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They found that the swirling disk of gas and dust

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orbiting the central supermassive black hole,

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called Sagittarius A*,

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is emitting a constant 
stream of flares with no periods of rest.

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Using Webb’s NIRCam (Near-Infrared Camera)

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to observe Sagittarius A* for a total of 48 hours  

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in 8- to 10-hour increments across one 
year,

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astronomers saw constantly changing,

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bubbling brightness, and then suddenly

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a big burst of brightness popped up.

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Then, it calmed down again.

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They couldn’t find a 
pattern, it appeared to be random.

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The activity profile of the black hole

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was new and exciting 
every time that the astronomers looked at it. 

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While the team expected to see flares, Sagittarius A*

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was more active than they anticipated.

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The observations revealed ongoing fireworks

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of various brightnesses and durations.

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The accretion disk surrounding the black hole  

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generated five to six big flares per day

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and several small sub-flares or bursts in between. 

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Although astrophysicists do not yet 
fully understand the processes at play,  

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they suspect two separate causes are responsible

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for the short bursts and longer flares.

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They believe that minor disturbances within

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the accretion disk likely generate the faint flickers.

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Specifically, turbulent 
fluctuations within the disk can compress  

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plasma to cause a temporary burst of radiation.

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For the big, bright flares astronomers think the

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cause is magnetic reconnection events,

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a process where two magnetic fields collide, releasing  

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releasing energy in the form of accelerated particles.

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Traveling at velocities near the speed of light,

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these particles emit bright bursts of radiation.

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These new findings could help physicists better

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understand the fundamental nature 
of black holes, how they interact  

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with their surrounding environments,

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and the dynamics and evolution of our own galactic home.

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"Webb Space Telescope"

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[ NASA Meatball ]