Dec 17 2007

‘Death Star’ Galaxy Black Hole Fires at Neighboring Galaxy

‘Death Star’ Galaxy Black Hole Fires at Neighboring Galaxy: Image Credit: NASAWASHINGTON — Dec 17, `07 — A powerful jet from a super massive black hole is blasting a nearby galaxy, according to new findings from NASA observatories. This never-before witnessed galactic violence may have a profound effect on planets in the jet’s path and trigger a burst of star formation in its destructive wake.

Known as 3C321, the system contains two galaxies in orbit around each other. Data from NASA’s Chandra X-ray Observatory show both galaxies contain super massive black holes at their centers, but the larger galaxy has a jet emanating from the vicinity of its black hole. The smaller galaxy apparently has swung into the path of this jet.

This “death star” galaxy was discovered through the combined efforts of both space and ground-based telescopes. NASA’s Chandra X-ray Observatory, Hubble Space Telescope, and Spitzer Space Telescope were part of the effort. The Very Large Array telescope, Socorro, N.M., and the Multi-Element Radio Linked Interferometer Network (MERLIN) telescopes in the United Kingdom also were needed for the finding.

“We’ve seen many jets produced by black holes, but this is the first time we’ve seen one punch into another galaxy like we’re seeing here,” said Dan Evans, a scientist at the Harvard-Smithsonian Center for Astrophysics and leader of the study. “This jet could be causing all sorts of problems for the smaller galaxy it is pummeling.”

Jets from super massive black holes produce high amounts of radiation, especially high-energy X-rays and gamma-rays, which can be lethal in large quantities. The combined effects of this radiation and particles traveling at almost the speed of light could severely damage the atmospheres of planets lying in the path of the jet. For example, protective layers of ozone in the upper atmosphere of planets could be destroyed.

Jets produced by super massive black holes transport enormous amounts of energy far from black holes and enable them to affect matter on scales vastly larger than the size of the black hole. Learning more about jets is a key goal for astrophysical research.

The effect of the jet on the companion galaxy is likely to be substantial, because the galaxies in 3C321 are extremely close at a distance of only about 20,000 light years apart. They lie approximately the same distance as Earth is from the center of the Milky Way galaxy.

A bright spot in the Very Large Array and MERLIN images shows where the jet has struck the side of the galaxy, dissipating some of the jet’s energy. The collision disrupted and deflected the jet.

Another unique aspect of the discovery in 3C321 is how relatively short-lived this event is on a cosmic time scale. Features seen in the Very Large Array and Chandra images indicate that the jet began impacting the galaxy about one million years ago, a small fraction of the system’s lifetime. This means such an alignment is quite rare in the nearby universe, making 3C321 an important opportunity to study such a phenomenon.

It is possible the event is not all bad news for the galaxy being struck by the jet. The massive influx of energy and radiation from the jet could induce the formation of large numbers of stars and planets after its initial wake of destruction is complete. More at NASA.


Dec 05 2007

STS-125: Final Shuttle Mission to Hubble Space Telescope

STS-125: Final Shuttle Mission to Hubble Space TelescopeSTS-125: Final Shuttle Mission to Hubble Space Telescope: Photo Credit: NASAWide Field Camera 3 (WFC3) will be the last main imaging camera to be installed.Houston — Dec 05, ‘07 — On August 07, 2008, after 20 years of hype, disappointment, blunders, triumphs and peerless glittering vistas of space and time, and four years after NASA decided to leave the Hubble Space Telescope to die in orbit, setting off public and Congressional outrage, a group of astronauts will ride to the telescope aboard the space shuttle Atlantis with wrenches in hand. Says NYTimes.

That, at least, is the plan.

STS-125: Final Shuttle Mission to Hubble Space Telescope: Hubble Image: Photo Credit: NASASTS-125: Final Shuttle Mission to Hubble Space TelescopeServicing Mission 4
NASA managers officially are targeting August 7, 2008, for the launch of the fifth and final space shuttle servicing mission to the Hubble Space Telescope. During the 11-day flight, Atlantis’ seven astronauts will repair and improve the observatory’s capabilities through 2013.

Mission planners have been working since last fall, when the flight was announced, to determine the best time in the shuttle manifest to support the needs of Hubble while minimizing the impact to International Space Station assembly. NASA also will support a “launch on need” flight during the Hubble mission. In the unlikely event a rescue flight becomes necessary, shuttle Endeavour currently is planned to lift off from Launch Pad 39-B at NASA’s Kennedy Space Center, Fla. However, managers constantly are evaluating the manifest to determine the best mission options.

Shuttle missions beyond the Hubble flight, designated STS-125, still are being assessed. Shuttle and station program officials will continue to consider options for the remainder of the shuttle flights to complete construction of the space station by 2010, when the fleet will be retired. Those target launch dates are subject to change.

Hubble Image: Photo Credit: NASAHubble Image: Photo Credit: NASAMore at NASA, NYTimes.


Nov 02 2007

Graceful Dance of Interacting Galaxies - ARP 87: Hubble Image

Tag: ESA, Hubble, NASA, Science, Space, Space Telescope, TechLuverJack @ 11:35 AM

Hubble_Image_ARP 87 Is a Stunning Pair of Interacting Galaxies

Two galaxies, containing a vast number of stars, swing past each other in a graceful dance choreographed by gravity, as seen by Hubble.
 

ESA News — Oct 30, ‘07 — The pair of galaxies collectively known as Arp 87 is among the hundreds of interacting and merging galaxies known in our nearby Universe. The Arp 87 pair was originally discovered and catalogued by astronomer Halton Arp in the 1970s. The ‘Arp’s Atlas of Peculiar Galaxies’ is a compilation of astronomical photographs using the Palomar 200-inch Hale and the 48-inch Samuel Oschin telescopes.

The two main players comprising Arp 87 are NGC 3808 and its companion NGC 3808A. NGC 3808 is a nearly face-on spiral galaxy with a bright ring of star formation and several prominent dust arms. Stars, gas, and dust flow from NGC 3808, forming an enveloping arm around its companion. NGC 3808A is a spiral galaxy seen edge-on and is surrounded by a rotating ring that contains stars and interstellar gas clouds. The ring is situated perpendicular to the plane of the host galaxy disk and is called a ‘polar ring.’ 

As seen in other mergers similar to Arp 87, the corkscrew shape of the tidal material (or bridge of shared matter) between the two galaxies suggests that some stars and gas drawn from the larger galaxy have been caught in the gravitational pull of the smaller one. The shapes of both galaxies have been distorted by their gravitational interaction with one another.Arp 87 is in the constellation Leo, the Lion, approximately 300 million light-years away from Earth. These observations were taken in February 2007 with the Wide Field Planetary Camera 2.  

Light from isolated blue, green, red, and infrared ranges was combined to form this color image.

Interacting galaxies often exhibit high rates of star formation. Many lines of evidence – colours of their starlight, intensity of emission lines from interstellar gas, far-infrared output from heated interstellar dust – support this fact. Some merging galaxies have the highest levels of star formation we can find anywhere in the nearby Universe. A major aspect of this excess star formation was properly revealed only when Hubble turned its imaging capabilities toward colliding galaxies. Among the observatory’s first discoveries was that galaxies with very active star formation contain large numbers of super star clusters – clusters more compact and richer in young stars than astronomers were accustomed to seeing in our galactic neighborhood 

Arp 87 is in the constellation Leo, the Lion, approximately 300 million light-years away from Earth. These observations were taken in February 2007 with the Wide Field Planetary Camera 2. Light from isolated blue, green, red, and infrared ranges was combined to form this colour image. More info & images at ESA.