First science from the Large Binocular Telescope

Mar 15, 2007 By William G. Gilroy
First science from the Large Binocular Telescope

An international team headed by University of Notre Dame astrophysicist Peter M. Garnavich has reported the first scientific result from the Large Binocular Telescope (LBT). The team imaged a distant “afterglow” of gamma ray burst “070125.”

The $120 million LBT is located atop Mount Graham, a 10,700-foot mountain in southeastern Arizona. The team of observers used the LBT’s “left-side” primary mirror and its “blue” camera to capture a detailed image of the afterglow of the gamma ray burst.

Gamma ray bursts are huge blasts of gamma rays that last for seconds or minutes. The blasts drive shocks into the surrounding gas that generate light from X-rays to radio waves and these “afterglows” are visible for just a few hours to a few days. The explosions are distant, often more than halfway back to the Big Bang. GRB 070125 was more than 7 billion light years away.

Garnavich’s team observed the gamma ray burst Feb. 21, almost a month after it exploded. The detection caught the burst at 26th magnitude. The magnitude scale is used by astronomers to measure the brightness of objects in space. The human eye can detect stars as faint as the 6th magnitude on a clear, dark night. The LBT was able to see a source that was 100 million times fainter than the limit of human vision.

“I have never before observed anything from the ground at the 26th magnitude and the seeing conditions at the LBT were not ideal at the time of the gammas ray burst observation, so we can, and will, go even deeper with this telescope,” Garnavich said.

The visible light of the gamma ray bursts afterglows are critical in understanding how gamma rays are generated in bursts. By following the optical decay, astrophysicists have been able to show that the energy comes out in a narrow beam and the bursts are only seen if the beam is aimed at the Earth.

“By studying the fading afterglow light, we show that the blast accelerates particles to nearly the speed of light and our deep images tell us exactly the opening angle of the jet aimed in our direction,” Garnavich said.

Garnavich was a member of a team of astronomers that in 2002 helped solve the mystery of one kind of gamma ray burst. The researchers found that the long blasts occur when stars explode and their cores collapse to form black holes. GRB 070125 probably created a black hole in a supernova collapse, but it is too distant to detect the explosion.

The LBT is unlike any other telescope because it uses twin 8.4-meter (27.6-foot) honeycomb mirrors that sit on a single mount, allowing it to view with the sharpness of a 23-meter telescope. The LBT achieved “first light,” or the first images of the night sky, in 2005 after the left mirror (called SX for “sinistra,” or left, in Italian) was installed and the blue-sensitive camera was taking pictures. The telescope is expected to be fully operational, with both of its enormous eyes wide open, later this year.

The LBT was built by an consortium that includes scientists from Notre Dame, the University of Arizona, Italy’s Istituto Nazionale di Astrofisica, Germany’s LBT Beteiligungsgesellschaft (representing the Max Planck Society), the Astrophysical Institute Potsdam, Heidelberg University, Ohio State University, the Universities of Minnesota and Virginia, and the Research Corporation.

Source: University of Notre Dame

Explore further: Unique pair of supermassive black holes in an ordinary galaxy discovered

add to favorites email to friend print save as pdf

Related Stories

Recommended for you

A star's early chemistry shapes life-friendly atmospheres

19 hours ago

Born in a disc of gas and rubble, planets eventually come together as larger and larger pieces of dust and rock stick together. They may be hundreds of light-years away from us, but astronomers can nevertheless ...

Image: X-raying the cosmos

Apr 22, 2014

When we gaze up at the night sky, we are only seeing part of the story. Unfortunately, some of the most powerful and energetic events in the Universe are invisible to our eyes – and to even the best optical ...

Mysteries of nearby planetary system's dynamics solved

Apr 22, 2014

Mysteries of one of the most fascinating nearby planetary systems now have been solved, report authors of a scientific paper to be published by the journal Monthly Notices of the Royal Astronomical Society in its ...

User comments : 0

More news stories

How many moons does Venus have?

There are dozens upon dozens of moons in the Solar System, ranging from airless worlds like Earth's Moon to those with an atmosphere (most notably, Saturn's Titan). Jupiter and Saturn have many moons each, ...

First-of-its-kind NASA space-weather project

A NASA scientist is launching a one-to-two-year pilot project this summer that takes advantage of U.S. high-voltage power transmission lines to measure a phenomenon that has caused widespread power outages ...

FDA proposes first regulations for e-cigarettes

The federal government wants to prohibit sales of electronic cigarettes to minors and require approval for new products and health warning labels under regulations being proposed by the Food and Drug Administration.

Brazil enacts Internet 'Bill of Rights'

Brazil's president signed into law on Wednesday a "Bill of Rights" for the digital age that aims to protect online privacy and promote the Internet as a public utility by barring telecommunications companies ...