Nearby galaxy boasts 2 monster black holes, both active
A study using NASA's Swift satellite and the Chandra X-ray Observatory has found a second supersized black hole at the heart of an unusual nearby galaxy already known to be sporting one. The galaxy, which is known as Markarian 739 or NGC 3758, lies 425 million light-years away toward the constellation Leo. Only about 11,000 light-years separate the two cores, each of which contains a black hole gorging on infalling gas.
The study will appear in a forthcoming issue of The Astrophysical Journal Letters.
"At the hearts of most large galaxies, including our own Milky Way, lies a supermassive black hole weighing millions of times the sun's mass," said Michael Koss, the study's lead author at NASA's Goddard Space Flight Center in Greenbelt, Md., and the University of Maryland in College Park (UMCP). "Some of them radiate billions of times as much energy as the sun."
Astronomers refer to galaxy centers exhibiting such intense emission as active galactic nuclei (AGN). Yet as common as monster black holes are, only about one percent of them are currently powerful AGN. Binary AGN are rarer still: Markarian 739 is only the second identified within half a billion light-years.
Many scientists think that disruptive events like galaxy collisions trigger AGN to switch on by sending large amounts of gas toward the black hole. As the gas spirals inward, it becomes extremely hot and radiates huge amounts of energy.
Since 2004, the Burst Alert Telescope (BAT) aboard Swift has been mapping high-energy X-ray sources all around the sky. The survey is sensitive to AGN up to 650 million light-years away and has uncovered dozens of previously unrecognized systems. Follow-up studies by Koss and colleagues published in 2010 reveal that about a quarter of the Swift BAT AGN were either interacting or in close pairs, with perhaps 60 percent of them poised to merge in another billion years.
"If two galaxies collide and each possesses a supermassive black hole, there should be times when both black holes switch on as AGN," said coauthor Richard Mushotzky, professor of astronomy at UMCP. "We weren't seeing many double AGN, so we turned to Chandra for help."
Swift's BAT instrument is scanning one-tenth of the sky at any given moment, its X-ray survey growing more sensitive every year as its exposure increases. Where Swift's BAT provided a wide-angle view, the X-ray telescope aboard the Chandra X-ray Observatory acted like a zoom lens and resolved details a hundred times smaller.
For decades, astronomers have known that the eastern nucleus of Markarian 739 contains a black hole that is actively accreting matter and generating prodigious energy. The Chandra study shows that its western neighbor is too. This makes the galaxy one of the nearest and clearest cases of a binary AGN.
The distance separating the two black holes is about a third of the distance separating the solar system from the center of our own galaxy. The dual AGN of Markarian 739 is the second-closest known, both in terms of distance from one another and distance from Earth. However, another galaxy known as NGC 6240 holds both records.
How did the second AGN remain hidden for so long? "Markarian 739 West shows no evidence of being an AGN in visible, ultraviolet and radio observations," said coauthor Sylvain Veilleux, a professor of astronomy at UMCP. "This highlights the critical importance of high-resolution observations at high X-ray energies in locating binary AGN."
Source: NASA/Goddard Space Flight Center
Articles on the same topic
- Gamma-ray flash came from star being eaten by massive black holeThu, 16 Jun 2011, 18:36:26 UTC
- Black hole kills star and blasts 3.8 billion light year beam at EarthThu, 16 Jun 2011, 18:36:05 UTC
- X-ray telescope finds new voracious black holes in early universeWed, 15 Jun 2011, 21:34:00 UTC
- Astronomers discover earliest black holes at dawn of universeWed, 15 Jun 2011, 17:36:44 UTC
- Rutgers contributes to findings that black holes were surprisingly common in early universeWed, 15 Jun 2011, 17:36:35 UTC
Other sources
- Black holes dating to the early universe uncoveredfrom LA Times - ScienceSat, 18 Jun 2011, 5:00:21 UTC
- Ultra-Bright Burst of Light Marks the Death Throes of a Star Being Eaten Alivefrom PopSciFri, 17 Jun 2011, 20:30:55 UTC
- Galaxy's Heart Beats in X-Raysfrom Space.comFri, 17 Jun 2011, 16:31:57 UTC
- Rare Sight: Giant Black Hole Devours Star, Fires Beams at Earthfrom Live ScienceFri, 17 Jun 2011, 14:30:30 UTC
- The Hole Picture: Growth of Black Holes and Galaxies Linked from an Early Agefrom Scientific AmericanFri, 17 Jun 2011, 14:30:23 UTC
- ScienceShot: Powerful Jet Being Produced by Star-Eating Black Holefrom Science NOWFri, 17 Jun 2011, 13:50:13 UTC
- Black hole eating star did cause huge blast: reportsfrom CBC: Technology & ScienceFri, 17 Jun 2011, 13:01:03 UTC
- Massive black hole devours starfrom BBC News: Science & NatureThu, 16 Jun 2011, 21:00:35 UTC
- Black hole shreds star, sparking gamma ray flashfrom Reuters:ScienceThu, 16 Jun 2011, 20:50:06 UTC
- Gamma-ray flash came from star being eaten by massive black holefrom Science DailyThu, 16 Jun 2011, 20:30:36 UTC
- Black hole kills star and blasts 3.8 billion light year beam at Earthfrom Science DailyThu, 16 Jun 2011, 20:30:34 UTC
- Unusual Celestial Event Was Black Hole Swallowing a Starfrom NY Times ScienceThu, 16 Jun 2011, 20:20:09 UTC
- Black Hole Caught Eating a Star, Gamma-Ray Flash Hintsfrom National GeographicThu, 16 Jun 2011, 20:00:27 UTC
- Giant black hole eats star, fires beams at Earthfrom CBSNews - ScienceThu, 16 Jun 2011, 20:00:20 UTC
- Unusual gamma-ray flash may have come from star being eaten by massive black holefrom PhysorgThu, 16 Jun 2011, 18:30:51 UTC
- Rare Sight: Giant Black Hole Devours Star, Fires Beams at Earthfrom Space.comThu, 16 Jun 2011, 18:30:21 UTC
- AUDIO: The oldest black holes in the universefrom BBC News: Science & NatureThu, 16 Jun 2011, 12:00:44 UTC
- Black hole growth, galaxy formation linkedfrom UPIThu, 16 Jun 2011, 7:00:24 UTC
- Black hole growth, galaxy formation linkedfrom UPIThu, 16 Jun 2011, 1:20:35 UTC
- X-ray telescope finds new voracious black holes in early universefrom Science DailyWed, 15 Jun 2011, 23:30:24 UTC
- Giant Black Holes Found at Dawn of the Universefrom National GeographicWed, 15 Jun 2011, 21:00:21 UTC
- Astronomers discover earliest black holes at dawn of universefrom Science DailyWed, 15 Jun 2011, 19:30:37 UTC
- X-ray analysis technique helps scientists determine that black holes grew voraciously in young galaxiesfrom Science DailyWed, 15 Jun 2011, 18:30:29 UTC
- NASA's Chandra finds massive black holes common in early universefrom Science DailyWed, 15 Jun 2011, 18:30:25 UTC
- Black holes found to exist since dawn of timefrom CBSNews - ScienceWed, 15 Jun 2011, 18:30:20 UTC
- Secrets of Earliest Black Holes Found in Ancient Galaxiesfrom Space.comWed, 15 Jun 2011, 17:30:46 UTC
- Most distant black holes ever found reveal secretsfrom CBC: Technology & ScienceWed, 15 Jun 2011, 17:30:29 UTC
- Bblack holes were surprisingly common in early universe: studyfrom PhysorgWed, 15 Jun 2011, 17:00:37 UTC
- Twin Supermassive Black Holes Found At Nearby Galaxy's Heartfrom PopSciMon, 13 Jun 2011, 22:00:24 UTC
- How Do Black Holes Form?from Space.comMon, 13 Jun 2011, 18:00:24 UTC
- Which Stars Form Black Holes?from Space.comMon, 13 Jun 2011, 18:00:23 UTC
- Nearby galaxy boasts two monster black holes, both activefrom Science DailySat, 11 Jun 2011, 0:30:27 UTC
- Monster Black Hole Twins Found Inside Galaxy's Bellyfrom Space.comFri, 10 Jun 2011, 22:30:18 UTC
- Our Galactic Neighbor Harbors a Second Black Holefrom Space.comFri, 10 Jun 2011, 20:00:32 UTC
- Nearby galaxy boasts two monster black holes, both activefrom PhysorgFri, 10 Jun 2011, 19:00:29 UTC