00:02Visit Chandra's Beautiful Universe
00:06Sagittarius A-Star
00:09As the Event Horizon Telescope, known as the EHT,
00:14collected data for its remarkable new image of the Milky Way's supermassive black hole,
00:19a legion of other telescopes, including three NASA X-ray observatories in space,
00:24was also watching.
00:27Astronomers are using these observations to learn more about how the black hole
00:31in the center of the Milky Way galaxy, known as Sagittarius A-Star, Sag A-Star for short,
00:38interacts with, and feeds off, its environment some 27,000 light-years from Earth.
00:44While the EHT observed Sag A-Star in April 2017 to make the new image,
00:51scientists in the collaboration also appeared at the same black hole
00:55with facilities that detect different wavelengths of light.
00:59In this multi-wavelength observing campaign,
01:02they assembled X-ray data from NASA's Chandra X-ray Observatory,
01:07Nuclear Spectroscopic Telescope, or NUSTAR,
01:10and the Neil Garrel Swift Observatory.
01:14Telescopes outside of NASA involved
01:16included the East Asian Very Long Baseline Interferometer,
01:20or VLBI, network that observed radio emission.
01:24There was also the global 3mm VLBI array,
01:28along with infrared data from the European Southern Observatory's
01:32Very Large Telescope in Chile.
01:35One important goal of this so-called multi-wavelength observing campaign
01:39was to catch X-ray flares,
01:41which are thought to be driven by magnetic processes
01:44similar to those seen on the Sun,
01:46but can be tens of millions of times more powerful.
01:50These flares occur approximately daily
01:53within the area of sky observed by the EHT,
01:57a region slightly larger than the event horizon of Sag A-Star,
02:01the point of no return for matter falling inward.
02:05Another goal was to gain a critical glimpse
02:07of what is happening on larger scales.
02:11While the EHT result shows striking similarities
02:14between Sag A-Star and the previous black hole it imaged, M87,
02:19the wider picture is much more complex.
02:27Both of these goals were successfully met.
02:30The researchers managed to catch X-ray flares,
02:33or outbursts, from Sag A-Star during the EHT observations,
02:37a faint one seen with Chandra and Swift,
02:40and a moderately bright one seen with Chandra and New Star.
02:44Astronomers have seen X-ray flares
02:46with a similar brightness to the latter with Chandra,
02:49but this is the first time that the EHT
02:51simultaneously observed Sag A-Star.
02:55This offers an extraordinary opportunity
02:57to identify the responsible mechanism
03:00using actual images.
03:03Astronomers were also able to learn more
03:05about the wider and complex picture of accretion.
03:09One of the biggest ongoing questions
03:11surrounding black holes
03:12is exactly how they collect, ingest,
03:15or even expel material orbiting them
03:18at near light speed
03:19in a process known as accretion.
03:22This process is fundamental
03:24to the formation and growth
03:26of planets, stars,
03:27and black holes of all sizes
03:29throughout the universe.
03:32Scientists will be able to use the data
03:34being released today
03:35to improve and hone their theoretical models
03:38of how black holes behave
03:40and interact with their surroundings.
03:42They will continue to study
03:44this unique combination
03:45to learn more about Sag A-Star
03:47and black holes throughout our universe.
03:50and learn more about Sag A-Star
04:20those people
04:23that they perceive
04:24like требing to encourage
04:25A-inky- lookin'st
04:30A- Dud-quela-
04:32A-arts-
04:32N-A-T-C
04:32Cheers!
04:33A-F-raD
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