Subscribe free to our newsletters via your
. 24/7 Space News .

Naked-Eye Gamma-Ray Burst Was Aimed Squarely At Earth
by Staff Writers
University Park PA (SPX) Sep 11, 2008

This artist's concept shows the "naked-eye" GRB close up. Observations suggest material shot outward in a two-component jet (white and green beams). NASA/Swift/Mary Pat Hrybyk-Keith and John Jones

Unparalleled data from satellites and observatories around the globe show that the jet from a powerful stellar explosion on 19 March was aimed almost directly at Earth. The event, called a gamma-ray burst, became bright enough for human eyes to see.

The burst's extraordinary brightness arose from a jet that shot material directly toward Earth at 99.99995 percent the speed of light.

NASA's Swift satellite detected the explosion -- formally called GRB 080319B -- at 2:13 a.m. U.S. Eastern Time that morning and pinpointed its position in the constellation Bootes.

The Swift satellite is controlled by Penn State University from its Mission Operations Center at University Park, and Penn State led in the development and assembly of two of the Swift satellite's three telescopes.

"Swift was designed to find unusual bursts," says Swift principal investigator Neil Gehrels at NASA's Goddard Space Flight Center. "We really hit the jackpot with this one."

In a paper to appear in Thursday's issue of Nature, Judith Racusin, a graduate student at Penn State and the lead author of the paper, and a team of 92 coauthors, report observations across the electromagnetic spectrum that began 30 minutes before the explosion and followed its afterglow for months.

The team's observations give astronomers the most detailed portrait of a gamma-ray burst ever made.

"At first, I thought something was wrong," Racusin recalls, because both Swift's X-Ray Telescope and its UltraViolet/Optical Telescope indicated they were effectively blinded by the brightness of the blast.

"Within minutes, as reports from other observers arrived, it was clear this explosion was an especially extraordinary event."

At the same moment Swift saw the burst, the Russian KONUS detector on NASA's Wind satellite also sensed the gamma rays and provided a wide view of their spectral structure. Simultaneously, a robotic wide-field optical camera called "Pi of the Sky" in Chile captured the burst's first visible light. The system is operated by a group of institutions from Poland.

Within the next 15 seconds, the burst brightened enough to be visible in a dark sky to human eyes. It briefly crested at magnitude 5.3 on the astronomical brightness scale. Incredibly, the dying star was 7.5 billion light-years away. Telescopes around the world were already studying the afterglow of another burst when GRB 080319B exploded just 10 degrees away.

TORTORA, a robotic wide-field optical camera operated in Chile by a Russian-Italian collaboration, also caught the early light. TORTORA's rapid imaging provides the most detailed look yet at visible light associated with a GRB's initial gamma-ray blast.

"We've been waiting a long time for this one," says TORTORA senior scientist Grigory Beskin of Russia's Special Astrophysical Observatory.

Gamma-ray bursts are the universe's most luminous explosions. Most occur when massive stars run out of nuclear fuel. As a star's core collapses, it creates a black hole or neutron star that, through processes not fully understood, drive powerful gas jets outward.

These jets punch through the collapsing star. As the jets shoot into space, they strike gas previously shed by the star and heat it, which generates bright afterglows.

The team believes the jet directed toward Earth contained an ultra-fast component just 0.4 of a degree across. This core resided within a slightly less energetic jet about 20 times wider. The broad component is more typical of what Swift sees from other bursts.

Perhaps every gamma-ray burst has a narrow jet, but astronomers miss it most of the time. The nearly head-on alignment required to see it occurs by chance only about once a decade.

Swift is managed by NASA's Goddard Space Flight Center and is controlled by Penn State. It was built and is being operated in collaboration with Penn State, the Los Alamos National Laboratory, and General Dynamics in the U.S.; the University of Leicester and Mullard Space Sciences Laboratory in the United Kingdom; Brera Observatory and the Italian Space Agency in Italy; plus partners in Germany and Japan.

The TORTORA camera is mounted on the Italian REM telescope at the European Southern Observatory in Chile. It was built and is being operated by a collaboration between Italy's Bologna State University and Brera Observatory and Russia's Special Astrophysical Observatory and Institute of Precise Instrumentation.


Related Links
Penn State
Stellar Chemistry, The Universe And All Within It

Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks DiggDigg RedditReddit GoogleGoogle

Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News

GLAST Burst Monitor Team Hard At Work
Huntsville AL (SPX) Jul 29, 2008
While only on orbit for 40 days and still in the process of a two-month checkout, NASA's Gamma-ray Large Area Telescope (GLAST) has already detected 12 powerful gamma-ray bursts, an encouraging harbinger of good things to come for this mission. The gamma-ray bursts were detected by the GLAST Burst Monitor (GBM), one of two instruments on the spacecraft. "We are thrilled to be detecting ... read more

Robot Scout Will Test New Lunar Landing Techniques For Future Explorers

NASA Seeks Input For Commercial Lunar Communications And Navigation

China's First Lunar Probe Satellite Normal After Eclipse

A Flash Of Insight: LCROSS Mission Update

Next Mars Soil Scoop Slated For Last Wet Lab Cell

Underneath Phoenix Lander 97 Sols After Touchdown

Mars Valleys Formed During Long Period Of Episodic Flooding

Spirit Still Biding Time

NASA Developing Fission Surface Power Technology

Space: The Not-So-Final Frontier

Emails from NASA head show discontent

Astronaut named head of Canadian Space Agency

The Politics Of Shenzhou

NW China Sandstorm No Threat To Launch Of Shenzhou-7 Spacecraft

China's rulers look to space to maintain Olympic pride

China announces spacewalk plans

Russia's Progress Spacecraft Buried In Pacific Ocean

European freighter detaches from space station

NASA TV to show ISS cargo ship arrival

Jules Verne Prepares For ISS Departure

ATK Propulsion And Composite Technologies Key To Successful Delta II Launch

United Launch Alliance Launches GeoEye-1 Commercial Satellite

Aurora Signs Contract To Build Minotaur IV Composite Structures

GeoEye-1 Satellite Launch Delayed Due To Hurricane Hanna

VLT Instrument Hints At The Presence Of Planets In Young Gas Discs

NASA Carl Sagan Fellows To Study Extraterrestrial Worlds

Universally Speaking, Earthlings Share A Nice Neighborhood

An Interstellar Mission Scenario

Modern Wireless Technologies Based On Decades Of Work

Clyde Space To Develop Lithium Polymer Battery For Small Satellites

Sims creator's long-awaited "playing god" game hits stores

Film created to protect small spacecraft

The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement