Posted on by Elizabeth Howell

Black Hole Steals Gas From Trillions Of Stars

A composite image (X-ray and optical wavelengths) showing galaxy cluster RX J1532.9+3021 and the black hole at its center. Credit: X-ray: NASA/CXC/Stanford/J.Hlavacek-Larrondo et al, Optical: NASA/ESA/STScI/M.Postman & CLASH team

Got gas?  The black hole in galaxy cluster RX J1532.9+3021 is keeping it all for itself and stopping trillions of stars from coming to be, according to new research. You can see data above from NASA’s Chandra X-ray Observatory (purple) and the Hubble Space Telescope (yellow).

The drama is taking place about 3.9 billion light-years from Earth, showing an extreme phenomenon that has been noted in other galaxies on smaller scales, Chandra officials stated.

“The large amount of hot gas near the center of the cluster presents a puzzle,” a statement read. “Hot gas glowing with X-rays should cool, and the dense gas in the center of the cluster should cool the fastest. The pressure in this cool central gas is then expected to drop, causing gas further out to sink in towards the galaxy, forming trillions of stars along the way. However, astronomers have found no such evidence for this burst of stars forming at the center of this cluster.”

Black hole with disc and jets visualization courtesy of ESA
Black hole with disc and jets visualization courtesy of ESA

What’s blocking the stars (according to data from Chandra and the National Science Foundation’s Karl G. Jansky Very Large Array) could be supersonic jets blasting from the black hole and shoving the gas in the area away, forming cavities on either side of the galaxy. These cavities, by the way, are immense — at 100,000 light-years across each, this makes them about as wide as our home galaxy, the Milky Way.

The big question is where that power came from. Perhaps the black hole is “ultramassive” (10 billion times of the sun) and has ample mass to shoot out those jets without eating itself up and producing radiation. Or, the black hole could be smaller (a billion times that of the sun) but spinning quickly, which would allow it to send out those jets.

You can find more details in a November 2013 paper from The Astrophysical Journal (also available in a prepublished version on Arxiv.) The research was led by Julie Hlavacek-Larrondo from Stanford University.

Source: Chandra X-Ray Observatory

Posted on by Nancy Atkinson

Your Weekend Movie: Beyond The Visible: The Story of the Very Large Array

The Very Large Array, one of the world's premier astronomical radio observatories, consists of 27 radio antennas in a Y-shaped configuration 50 miles west of Socorro, New Mexico. Each antenna is 82 feet (25 m) in diameter. The data from the antennas is combined electronically to give the resolution of an antenna 22 miles (36 km) across. Image courtesy of NRAO/AUI and NRAO

While some of you will no doubt be heading to the theaters to see the new release of “Gravity,” for those that want to stay in for the weekend, here’s the perfect short film. The National Radio Astronomy Observatory (NRAO) has released a new 24-minute film about the recently renovated Karl G. Jansky Very Large Array (VLA) radio telescope. The film is narrated by Academy Award-winning actress Jodie Foster, star of the 1997 Warner Brothers film, “Contact,” which was filmed in part at the VLA.

“In ‘Contact,’ I played the role of an astronomer using the VLA,” Foster said. “In narrating this new film for the VLA Visitor Center, I have the privilege of introducing tomorrow’s scientists, technicians, and engineers to the amazing complexities of this great telescope, and to the wonders of the universe that it reveals.”

Beyond The Visible: The Story of the Very Large Array from NRAO Outreach on Vimeo.

From NRAO’s press release:

Titled “Beyond the Visible,” the film tells the behind-the-scenes story of the operation and scientific achievements of the VLA, which has been at the forefront of astrophysical research since its dedication in 1980. Spectacular ground and aerial footage of the iconic radio telescope is augmented by first-person interviews with staffers who keep the telescope working and scientists who use it to discover exciting new facts about the universe. The film also depicts many of the technical tasks needed to keep the array functioning at the forefront of science.

“Since the last film for the Visitor Center was produced in 2002, we’ve completed a massive technological upgrade that turned the VLA into a completely new and vastly more powerful tool for cutting-edge science,” said Dale Frail, NRAO’s Director for New Mexico Operations. “It was time to update the story we tell our visitors,” he added.

The film replaces an earlier video that ran at the VLA Visitor Center auditorium, which is visited by some 20,000 people annually. You can’t currently go to the Visitor Center to see the new film at the moment, however, because of the US federal government shutdown. So, watch it here. Hopefully the shutdown will be resolved soon so that people can resume their visits to the VLA.

Posted on by Nancy Atkinson

Cosmic Volcano Erupting in M87

A new composite image of M87 features X-rays from Chandra (blue) and radio emission from the Very Large Array (red-orange). Credit: NASA/Chandra

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It’s the Eyjafjallajokull of space! Chandra and the VLA have teamed up to find an erupting galactic “super-volcano” in the massive galaxy M87. Hot gas glowing in X-ray light (shown in blue) surrounds M87, and as the gas cools, it can fall toward the galaxy’s center where it should continue to cool even faster and form new stars. But radio observations with the Very Large Array (red-orange) suggest that in M87 jets of very energetic particles produced by the black hole interrupt this process. These jets lift up the relatively cool gas near the center of the galaxy and produce shock waves in the galaxy’s atmosphere because of their supersonic speed. Scientists say this action is similar to what took place with the Eyjafjallajokull volcano in Iceland that occurred in 2010.

With Eyjafjallajokull, pockets of hot gas blasted through the surface of the lava, generating shock waves that can be seen passing through the grey smoke of the volcano. This hot gas then rises up in the atmosphere, dragging the dark ash with it. Remember the close-up movie of the volcano’s eruption — (see below)? Shock waves propagating in the smoke are followed by the rise of dark ash clouds into the atmosphere.

In the case of this cosmic volcano in M87, the energetic particles produced in the vicinity of the black hole rise through the X-ray emitting atmosphere of the cluster, lifting up the coolest gas near the center of M87 in their wake. This is similar to the hot volcanic gases that drag up the clouds of dark ash. And just like the volcano here on Earth, shock waves can be seen when the black hole pumps energetic particles into the cluster gas. The Chandra team has provided a labeled version of the image which shows the energetic particles, cool gas and shock waves.


M87 is about 50 million light years from Earth and lies at the center of the Virgo cluster, which contains thousands of galaxies.

Source: Chandra