PSU to control satellite studying gamma ray bursts
By the end of today, a massive star somewhere in the universe will collapse on itself to form a new black hole with a gravitational pull so strong that not even light can escape.
The star probably won’t go out without one last hurrah — or a gamma ray burst, to be more precise.
Swift, a $250 million NASA spacecraft designed to detect these quick, powerful explosions, is scheduled to be launched into orbit at 12:09 p.m. today from the Cape Canaveral Air Force Station in Florida.
If all goes well at liftoff, astronomers and engineers at Penn State University will take control of the satellite about 80 minutes later from a mission control center in University Park, near the heart of campus.
“We are looking forward to the culmination of five years of effort and the operational phase of the mission,” said Penn State’s Swift project manager Thomas Taylor, who also heads the university’s Center for Space Research Programs. “We’ve done many simulations, so we are prepared and very confident that nothing will go wrong.”
The Swift mission was organized by the National Aeronautics and Space Administration in collaboration with researchers in Great Britain and Italy.
Scientists hope the spacecraft will answer one of the great cosmic mysteries of our time about the causes and consequences of gamma ray bursts.
“Every aspect of gamma ray bursts boggles the mind,” said Neil Gehrels, Swift’s principal investigator at NASA’s Goddard Space Flight Center in Greenbelt, Md. “They last just a few seconds, but they are very bright. If you had gamma ray vision, it would be like sitting in a dark room with a flash bulb going off.”
Gamma ray bursts are intense, fleeting flashes of gamma radiation that shine as bright as a million-trillion suns and occur about once per day in galaxies that are billions of light years away. Each burst is followed by an afterglow created by the emission of less-energetic forms of electromagnetic radiation, which can last for weeks.
Gamma ray bursts are the second-most powerful explosions in the universe, trailing only the Big Bang, the theorized cataclysmic beginning of space and time.
The bursts were discovered accidentally about 40 years ago by U.S. satellites monitoring secret Soviet nuclear tests. A systematic survey by NASA’s Compton Gamma Ray Observatory in the 1990s revealed that these violent explosions come from all directions and occur in galaxies far beyond the Milky Way.
Astronomers speculate the bursts are triggered by the collapse of massive dying stars — events called hypernovas that form black holes. Scientists hypothesize that bursts also might be set off by the merger of two neutron stars, or the extremely compact remains of a dead star.
Determining the origin for these puzzling phenomena and answering questions about the early universe are the main objectives of Swift, which will analyze about 200 bursts in the next two years.
The compact Swift — at 18 1/2 feet long, 17 3/4 feet wide and weighing 668 pounds — is equipped with three telescopes that will allow for the fastest, most-detailed observations of gamma ray bursts to date, starting about 45 days following its launch, Gehrels said.
After initial detection of an explosion with a special instrument called the Burst Alert Telescope, Swift will maneuver rapidly to focus on the burst and its afterglow using X-ray and ultraviolet telescopes designed by engineers at Penn State and in Europe.
The satellite also will relay coordinates of any bursts it detects to ground-based telescopes, allowing a network of astronomers around the world to track the cosmic events before the afterglow fades.
About 6 billion bytes of data about gamma ray bursts from Swift will flow through the mission operations center in University Park every day, and scientists there will be responsible for commanding the satellite and planning its observations.
Swift will be launched by a Delta 7320 rocket designed by General Dynamics, which will maintain joint control of the satellite for the first 30 days of its flight.
As of late Tuesday, the weather forecast at the Cape Canaveral launch site called for clear skies, and there were no technical problems with the spacecraft, NASA said.
“After (Hurricanes) Charley, Frances, Jeanne and several days of high winds, I am happy to say I don’t expect any weather problems,” said Joel Tumbiolo, a weather officer with the Air Force at Cape Canaveral.
Thursday is the rain day for the launch, Tumbiolo said.
Gamma ray bursts
Gamma ray bursts are short-lived, extremely intense flashes of gamma rays that likely signal the birth of a black hole through the explosion of a massive star. Most gamma ray bursts likely originate billions of light years away and last only a few seconds. Their origin is among the great cosmic mysteries that scientists hope will be solved by NASA’s Swift spacecraft mission scheduled for launch today.