Genesis of an Artificial Meteor
|Genesis re-entry with solar wind in tow.|
Scientists expect to get the most detailed look at a hypervelocity re-entry when NASA uses an aerial laboratory to observe the fiery return of the Genesis sample return capsule from interplanetary space.
On Sept. 8, 2004, NASA will send the U.S. Air Force’s Flying Infrared Signatures Technologies Aircraft (FISTA) to an altitude of 39,000 feet for a front row seat to the sample return capsule’s (SRC) fiery re-entry. The aircraft will be fitted with multiple scientific instruments including ultraviolet, infrared and visible-light spectrometers, as well as high-resolution still cameras and high-definition video cameras. Researchers from NASA Ames Research Center, located in California’s Silicon Valley, and the SETI Institute, Mountain View, Calif., will observe this ‘artificial’ meteor. Principal investigator and meteor astronomer Peter Jenniskens of the SETI Institute is leading the diverse and independent science team.
"Genesis will be the first of several return capsules as part of NASA’s ongoing science and exploration missions," said Paul Wercinski, the Genesis observation campaign project manager at NASA Ames. "This is a unique opportunity to study the physics of re-entry up close and assess the effectiveness of thermal protection systems for re-entry vehicles. What we learn from Genesis will be useful for those future missions," he added.
|The moment of Genesis reentry over the northwestern US, prior to when the helicopter lowers its fishing pole hook and snags the Genesis parachute.|
Genesis, launched in August 2001, captured samples from the storehouse of 99 percent of all the material in our solar system – the sun. After they return, these samples, collected on wafers of gold, sapphire, silicone and diamond, will be analyzed by scientists. The samples will provide vital information on the composition of the sun, and shed light on the origins of our solar system.
Scientists at NASA Ames are keenly interested in the airborne observations in order to understand how the capsule’s heat shield performs under these ‘super-orbital speed entry’ conditions. These observations may help develop the tools used to simulate re-entry conditions.
"One of our key objectives is to acquire flight data that substantiate our ability to predict the amount of thermal radiation that heats the capsule during reentry," said Dr. Dean Kontinos, chief of the NASA Ames Reacting Flow Environments Branch. "These thermal radiation models are essential for designing future exploration vehicles."
|A composite of Leonid meteor images recorded by a CCD camera onboard the MSX satellite|
The Genesis SRC will return from interplanetary space and turn briefly into a bright meteor over Oregon and Nevada. The capsule will experience peak heating conditions as it decelerates near the Oregon/Nevada border enroute to Utah. During this heating phase of the capsule, the airborne observers will train their cameras at the ‘artificial’ meteor. The Genesis mission will end over the U.S. Air Force Utah Test and Training Range, where the capsule will be recovered.
The re-entry is of particular interest to meteor astronomers since the SRC is an analog to meter-sized asteroids that deposit organic material in Earth’s atmosphere. The return of the Genesis capsule is like a meteor on queue, giving scientists a unique opportunity to study what happens during re-entry.
"We are interested in the physical and chemical conditions in the shockwave that can change the organic material in asteroids into pre-biotic molecules for life’s origins," Jenniskens said.