X

Aggregator

James Webb Space Telescope Discovers How Black Holes Feed Themselves

Slashdot
2 months ago
"Thanks to the James Webb Space Telescope, astronomers have been given a glimpse of the mechanisms that supermassive black holes use to feed themselves," reports Space.com: The powerful cosmic titans get really puzzling when astronomers using the JWST spot them before the universe was even 1 billion years old. That's because the mechanisms by which black holes devour matter to grow and then merge to create even more massive black holes should take at least 1 billion years to achieve supermassive status. This is even more confusing because theories also say the most ravenously feeding black holes (and thus the fastest growing) should also push the matter they use for this growth away, in effect putting themselves on a diet. So, with all this in mind, how did supermassive black holes grow so rapidly in the early universe? One explanation suggests supermassive black holes push away gas, starving themselves as predicted, but also that this matter eventually cools and falls back to the black hole. That would allow for another period of feeding and thus growth. This explanation further suggests that as this gas cools down, it forms "streamers," or filaments, of gas just a few hundred light-years wide but which stretch thousands of light-years long. These would fall back to the center of the galaxy and form a swirling disk around its incumbent black hole, once again feeding it and triggering a new period of growth. This would then restart the jets from the black hole, which would again cut off the cosmic titan's food supply, allowing the whole process to begin once more. The process would in essence be a self-regulating cycle of feasting followed by fasting. However, the connection between these filaments and supermassive black holes has been elusive, meaning this mechanism has resisted confirmation. To solve the mystery of feasting black holes, the JWST turned its attention to a relatively close AGN situated at the heart of the central galaxy of the Centaurus Cluster, NGC 4696, located just 145 million light-years from Earth. The Hubble Space Telescope previously studied this galaxy, uncovering a strange, hook-shaped swirl of gas near the central supermassive black hole of NGC 4696. The JWST followed up this discovery by producing a detailed map of gas flowing at the heart of the galaxy. This revealed the hook-shaped feature is around 800 light-years wide and is composed of gas moving at incredible speeds of around 1.3 million miles per hour (600 kilometers per second). More excitingly, the swirl of gas appears to be connected to a vast filament of material falling in toward the central supermassive black hole. The team tested the JWST observations against a computer simulation, finding gas in the infalling filament scenario would indeed take a shape similar to that seen in NGC 4696. "JWST is now showing us the final link of this closed loop," team member Helen Russell of the School of Physics and Astronomy at the University of Nottingham in the U.K. said in the statement. "The vast filamentary network of gas flows ultimately funnels gas down to a disk that fuels the black hole." The team's research was published on Wednesday (July 16) in the Astrophysical Journal Letters. "We are finally seeing this self-sustaining cycle in action," team leader Julie Hlavacek-Larrondo of the Université de Montréal said in a statement.

Read more of this story at Slashdot.

EditorDavid

Robot 'Decapitated' in World's First-Ever Humanoid UFC Fight

Slashdot
2 months ago
"A humanoid robot lost its head," reports Newsweek, "during the world's first free-combat tournament for full-sized humanoid robots." The Ultimate Robot Knock-out Legend competition began Thursday in Shenzhen, China, according to the article, with local robotics company EngineAI providing $40,000 of their "T800" robots (yes, named after The Terminator) to 32 participating teams from around the world: A video shared of the combat on YouTube by local news outlet Shenzhen Story, showed that even after one of the robots had its head practically knocked off its shoulders, it continued to fight, throwing punches at its opponent and kicking into the air... [White humanoid robot "White Eagle"] landed a high kick to the head of its black opponent, "Matador," which made the robot's head rock precariously in its socket before rolling completely out of place. The two continued to spar as Matador's head was swinging from its socket until eventually the robot fell, crushing its head underneath its body. Matador tried to scramble back to its feet, but its head flew off and the robot then collapsed back down. The White Eagle did a celebratory dance for the crowd as the fight concluded, and did a move that mimicked that of someone flexing their biceps. The White Eagle waited in the ring, fists still up, as Matador was carried away, occasionally doing a few more dance moves... Per a report by Global Times, the winning team will be awarded a gold championship belt worth $1.44 million (10 million yuan) by the event organizer. It's a strange fight. The robots sometimes seem unaware of where their opponent is, facing the wrong direction or throwing kicks and punches in the air. In the first round White Eagle just knocks over Matador, who then isn't able to stand back up. (And White Eagle again appears to do a victorious dance.) EngineAI's site says they aim to "promote the development of robot combat events toward greater professionalism, scale, and industrialization," while fostering innovation and global collaboration. Thanks to Slashdot reader pbahra for sharing the news.

Read more of this story at Slashdot.

EditorDavid