Swift Survey Finds 'Smoking Gun' Of Black Hole Activation

The optical counterparts of many active galactic nuclei (circled) detected by the Swift BAT Hard X-ray Survey clearly show galaxies in the process of merging. These images, taken with the 2.1-meter telescope at Kitt Peak National Observatory in Arizona, show galaxy shapes that are either physically intertwined or distorted by the gravity of nearby neighbors. These AGN were known prior to the Swift survey, but Swift has found dozens of new ones in more distant galaxies.

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.

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 of the black hole in our own Milky Way galaxy. The study will appear in the June 20 issue of The Astrophysical Journal Letters.

The intense emission from galaxy centers, or nuclei, arises near a supermassive black hole containing between a million and a billion times the sun's mass. Giving off as much as 10 billion times the sun's energy, some of these active galactic nuclei (AGN) are the most luminous objects in the universe. They include quasars and blazars.

"Theorists have shown that the violence in galaxy mergers can feed a galaxy's central black hole," said Michael Koss, the study's lead author and a graduate student at the University of Maryland in College Park. "The study elegantly explains how the black holes switched on."

Herschel Finds a Hole in Space

The dark hole seen in the green cloud at the top of this image was likely carved out by multiple jets and blasts of radiation. The hole was originally thought to be a really dark cloud, but this new infrared picture from the Herschel space observatory and the National Optical Astronomy Observatory on Kitt Peak near Tucson, reveals that the dark spot is actually a gap in a "nest" of gas and dust containing fledgling stars. Herschel's infrared eyes are designed to see into clouds, so the fact that it saw a dark patch of space told astronomers that they were indeed looking at a hole.

The glowing, green cloud around the hole is called NGC 1999. It contains a fairly bright star, called V38O Ori, which is heating up the dust and creating the bright greenish glow. V380 Ori is a triple star system - one of these three stars appears to have launched a jet that helped clear the hole, as well as other jets and stellar radiation.

The red, filamentary glow extending through the middle of the image is a cloud of cold, dense gas and dust -- the raw material from which new stars are forming. Three new, embryonic stars can bee seen as the triangle of orangish, yellow-white spots. Bipolar jets are visible streaming out of one of these stars in blue. The dark region below and to the right of the top orange-white star of the triangle is thought to be another hole carved by jets from the star. This possible hole is not yet lit up by a star, as is the case with the hole seen above it.

Shorter-wavelength infrared light captured by the "NEWFIRM" camera at the National Optical Astronomy Observatory is colored blue, while longer-wavelength infrared light seen by the photodetector array camera and spectrometer instrument on Herschel is green and red.

Herschel is a European Space Agency cornerstone mission, with science instruments provided by consortia of European institutes and with important participation by NASA. NASA's Herschel Project Office is based at NASA's Jet Propulsion Laboratory. JPL contributed mission-enabling technology for two of Herschel's three science instruments. The NASA Herschel Science Center, part of the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena, supports the United States astronomical community.

Processing Operations Under Way at Dryden

Technicians working at NASA’s Dryden Flight Research Center in California are moving carefully through a regimen to ready the shuttle for its cross-country ferry flight atop a modified 747 back to NASA's Kennedy Space Center in Florida. That trip could begin as soon as Friday morning, although weather and other technical issues could push that date back.

Among turnaround tasks already completed by Monday morning, United Space Alliance technicians finished shuttle main engine drying operations, offloaded cryogenics, removed the external tank separation camera and inerted the Power Reactant Storage and Distribution system battery tank. Purging of the Orbital Maneuvering System fluid lines and valves and other tasks requiring access to the aft end of the shuttle are in process Monday.

Processing managers hope to begin the all-day process of purging and offloading of residual fuels and oxidizers and other hazardous chemicals early Tuesday morning.