Latest Seyfert galaxy Stories
Astronomers studying the galaxy NGC 4151 with ESA's XMM-Newton space observatory have detected X-rays emitted and then reflected by ionised iron atoms very close to the supermassive black hole hosted at the galaxy's core. By measuring the time delays occurring in these 'reverberation' events, they were able to map the vicinity of this black hole in unprecedented detail. Supermassive black holes are enormous concentrations of matter, weighing millions to billions of times the mass of the...
WASHINGTON, May 26 /PRNewswire-USNewswire/ -- Data from an ongoing survey by NASA's Swift satellite have helped astronomers solve a decades-long mystery about why a small percentage of black holes emit vast amounts of energy. (Logo: http://www.newscom.com/cgi-bin/prnh/20081007/38461LOGO) Only about one percent of supermassive black holes exhibit this behavior. The new findings confirm that black holes "light up" when galaxies collide, and the data may offer insight into the future behavior...
Back in June 1991, just before the launch of NASA's Compton Gamma-Ray Observatory, astronomers knew of gamma rays from exactly one galaxy beyond our own. To their surprise and delight, the satellite captured similar emissions from dozens of other galaxies. Now its successor, the Fermi Gamma-ray Space Telescope, is filling in the picture with new finds of its own."Compton showed us that two classes of active galaxies emitted gamma rays -- blazars and radio galaxies," said Luigi...
Using new data from ESA's XMM-Newton spaceborne observatory, astronomers have probed closer than ever to a supermassive black hole lying deep at the core of a distant active galaxy.The galaxy "“ known as 1H0707-495 "“ was observed during four 48-hr-long orbits of XMM-Newton around Earth, starting in January 2008. The black hole at its center was thought to be partially obscured from view by intervening clouds of gas and dust, but these current observations have revealed the innermost...
Radio-telescope images have revealed previously-unseen galactic cannibalism -- a triggering event that leads to feeding frenzies by gigantic black holes at the cores of galaxies. Astronomers have long suspected that the extra-bright cores of spiral galaxies called Seyfert galaxies are powered by supermassive black holes consuming material. However, they could not see how the material is started on its journey toward the black hole.One leading theory said that Seyfert galaxies have been...
Dr. Carl K. Seyfert Jr., a longtime Buffalo State College geology professor, died Sunday in Erie County Medical Center from injuries in a car crash in Amherst on Oct. 16. He was 69. Born in Pecos, Texas, Dr. Seyfert graduated from Hillsboro High School in Nashville, Tenn., and earned a bachelor's degree at Vanderbilt University and a doctorate in geology from Stanford University. Born into a scientific family, his father was Dr. Carl K. Seyfert Sr., a Vanderbilt University astronomer who...
An international team of astronomers using NASA's Swift satellite and the Japanese/U.S. Suzaku X-ray observatory has discovered a new class of active galactic nuclei (AGN).By now, you'd think that astronomers would have found all the different classes of AGN "” extraordinarily energetic cores of galaxies powered by accreting supermassive black holes. AGN such as quasars, blazars, and Seyfert galaxies are among the most luminous objects in our Universe, often pouring out the energy of...
NASA scientists using the Swift satellite have conducted the first complete census of galaxies with active, central black holes, a project that scanned the entire sky several times over a nine-month period. The all-sky survey contains more than 200 supermassive black holes called Active Galactic Nuclei, or AGN, and provides a definitive census of black hole activity in the local universe. The team uncovered many new black holes that were previously missed, even in well-studied galaxies, and...
ITHACA, N.Y. - The office that astronomer Lei Hao shares with her fellow research associates on the first floor of the Space Sciences Building at Cornell University is tidy and organized. But Hao has been thinking a lot lately about dust. Actually, she's recently found a great deal of it. And she's thrilled. The dust in question is between 0.88 billion and 2.4 billion light years away from Hao's office, in galaxies scientists classify as active galactic nuclei (AGNs). By confirming that the...
ITHACA, N.Y. -- The office that astronomer Lei Hao shares with her fellow research associates on the first floor of the Space Sciences Building at Cornell University is tidy and organized. But Hao has been thinking a lot lately about dust. Actually, she's recently found a great deal of it. And she's thrilled. The dust in question is between 0.88 billion and 2.4 billion light years away from Hao's office, in galaxies scientists classify as active galactic nuclei (AGNs). By confirming that the...
