Page One

A NASA satellite designed and built by scientists at UC Berkeley was placed into orbit Tuesday to study how solar flares are produced in the Sun's atmosphere. 

The 645-pound High Energy Solar Spectroscopic Imager was fixed inside a Pegasus rocket, attached to the belly of an Orbital Stargazer, and carried to 39,000 feet.  

The Pegasus was dropped at 3:56 p.m. EST and free fell for about five seconds, then ignited and climbed to 373 miles above the Earth and delivered the HESSI spacecraft into a circular orbit. 

The HESSI will be pointed permanently at the Sun to study the intense energy that accompanies solar flares and coronal mass ejections.  

The project was timed to coincide with the peak of the 11-year solar cycle, when the sun is most active with sunspots, solar flares and other activity.  

“A solar flare is an explosion that happens very close to the surface of the sun,” said Robert Lin, Professor of Physics, UC Berkeley, and Principal Investigator for HESSI. “With a coronal mass ejection a large hunk of matter gets thrown out into space, roughly a billion tons of ionized gas.” Lin compared that with a four foot fluorescent light, which has roughly one tenth of a gram of ionized gas.  

“It’s good to know how the sun works, it gives life and its close by,” said David Smith, spectrometer scientist for the project. “It stores up energy, gets twisted up like a rubber band and suddenly releases that energy. We want to know how and why.” 

The solar powered satellite will align its orbit with electromagnetic coils that push against Earth’s magnetic field.  

The $85 million project falls under the NASA Small Explorer program, which was instituted by NASA during the past decade with the rationale that smaller projects would be cheaper, more efficient, and carry less bureaucracy.  

For more information visit: http://hessi.ssl.berkeley.edu/, or www.nasa.gov.