NASA's RXTE Helps Pinpoint Launch of 'Bullets' in a Black Hole's Jet

  • Released Tuesday, January 10, 2012
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Using observations from NASA's Rossi X-ray Timing Explorer (RXTE) satellite and the National Science Foundation's (NSF) Very Long Baseline Array (VLBA) radio telescope, an international team of astronomers has identified the moment when a black hole in our galaxy launched superfast knots of gas into space.

Racing outward at about one-quarter the speed of light, these "bullets" of ionized gas are thought to arise from a region located just outside the black hole's event horizon, the point beyond which nothing can escape.

The research centered on the mid-2009 outburst of a binary system known as H1743-322, located about 28,000 light-years away toward the constellation Scorpius. Discovered by NASA's HEAO-1 satellite in 1977, the system is composed of a normal star and a black hole of modest but unknown masses.

Their orbit around each other is measured in days, which puts them so close together that the black hole pulls a continuous stream of matter from its stellar companion. The flowing gas forms a flattened accretion disk millions of miles across, several times wider than our sun, centered on the black hole. As matter swirls inward, it is compressed and heated to tens of millions of degrees, so hot that it emits X-rays.

Some of the infalling matter becomes re-directed out of the accretion disk as dual, oppositely directed jets. Most of the time, the jets consist of a steady flow of particles. Occasionally, though, they morph into more powerful outflows that hurl massive gas blobs at significant fractions of the speed of light.

Animation of black hole system H1743-322. In this animation, an X-ray hot spot in the gas around the black hole produced signals of rising frequency as the spot moved closer to the black hole. When the bullets were ejected June 3, the hot spot vanished.

Radio imaging by the Very Long Baseline Array (top row), combined with simultaneous X-ray observations by NASA's RXTE (middle), captured the transient ejection of massive gas "bullets" by the black hole binary H1743-322 during its 2009 outburst. By tracking the motion of these bullets with the VLBA, astronomers were able to link the ejection event to the disappearance of X-ray signals seen in RXTE data. These signals, called quasi-periodic oscillations (QPOs), vanished two days earlier than the onset of the radio flare that astronomers previously had assumed signaled the ejection. Credit: NRAO and NASA/Goddard Space Flight Center

Radio imaging by the Very Long Baseline Array (top row), combined with simultaneous X-ray observations by NASA's RXTE (middle), captured the transient ejection of massive gas "bullets" by the black hole binary H1743-322 during its 2009 outburst. By tracking the motion of these bullets with the VLBA, astronomers were able to link the ejection event to the disappearance of X-ray signals seen in RXTE data. These signals, called quasi-periodic oscillations (QPOs), vanished two days earlier than the onset of the radio flare that astronomers previously had assumed signaled the ejection.

Credit: NRAO and NASA/Goddard Space Flight Center

This 327-MHz radio view of the center of our galaxy highlights the position of the black hole system H1743-322, as well as other features. Labels.Credit: J. Miller-Jones (ICRAR-Curtin Univ.) and C. Brogan (NRAO)

This 327-MHz radio view of the center of our galaxy highlights the position of the black hole system H1743-322, as well as other features. Labels.

Credit: J. Miller-Jones (ICRAR-Curtin Univ.) and C. Brogan (NRAO)

This 327-MHz radio view of the center of our galaxy highlights the position of the black hole system H1743-322, as well as other features. No Labels.Credit: J. Miller-Jones (ICRAR-Curtin Univ.) and C. Brogan (NRAO)

This 327-MHz radio view of the center of our galaxy highlights the position of the black hole system H1743-322, as well as other features. No Labels.

Credit: J. Miller-Jones (ICRAR-Curtin Univ.) and C. Brogan (NRAO)

The Very Long Baseline Array is a system of ten radio telescopes spanning 5,500 miles that work together as the world's largest dedicated astronomical instrument. Each station consists of an 82-foot-diameter, 240-ton dish antenna and an adjacent control building. Labels.

The Very Long Baseline Array is a system of ten radio telescopes spanning 5,500 miles that work together as the world's largest dedicated astronomical instrument. Each station consists of an 82-foot-diameter, 240-ton dish antenna and an adjacent control building. Labels.

The Very Long Baseline Array is a system of ten radio telescopes spanning 5,500 miles that work together as the world's largest dedicated astronomical instrument. Each station consists of an 82-foot-diameter, 240-ton dish antenna and an adjacent control building. No Labels

The Very Long Baseline Array is a system of ten radio telescopes spanning 5,500 miles that work together as the world's largest dedicated astronomical instrument. Each station consists of an 82-foot-diameter, 240-ton dish antenna and an adjacent control building. No Labels

For More Information

See http://www.nasa.gov/topics/universe/features/rxte-bullets.html

Credits

Please give credit for this item to:
NASA/Goddard Space Flight Center. However, individual images should be credited as indicated above.

This page was originally published on Tuesday, January 10, 2012.
This page was last updated on Wednesday, May 3, 2023 at 1:53 PM EDT.

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  • Fermi and RXTE AAS releases (ID: 2012005)
    Tuesday, January 10, 2012 at 5:00AM
    Produced by - Robert Crippen (NASA)