First Science is Complete
The Stratospheric Observatory for Infrared Astronomy's first series of three science missions took to the skies over a nine-day span that concluded Dec. 8. The missions gave scientists a feel for how the observatory is going to perform and a look at some of the science they will be able to achieve with it.
"The flights were outstanding and have exceeded our expectations. Everything worked great," said Bob Meyer, SOFIA program manager. "The observatory is not fully developed. Some of the capabilities are not where we want them yet. For example, the pointing stability and accuracy was good for these flights, but we still have room for improvement."
For that reason, the observatory science is beginning at a slow pace as the development effort on the aircraft continues. Brent Cobleigh, SOFIA platform manager, said the observatory will undergo additional modifications next year to meet the challenges of an expected 20-year operation. A key modification will be a cockpit upgrade from dials and gauges to a modern electronic, or "glass," cockpit. Also planned are telescope improvements and a checklist of items that will improve the observatory's overall performance and capabilities, he said.
Erick Young, SOFIA science mission operations director for Universities Space Research Association, said he was extremely pleased with the first science flights, which exceeded all of the requirements.
"We are seeking better performance as we go higher," Young said. "I think the hardest thing is to get all of the different pieces to work together properly. The only way you can tell if all the elements are working properly is to actually do it in real flight. So what these flights have proven is that all of the pieces do work together, and well enough to produce great science."
Pam Marcum, SOFIA project scientist, said the flight went better than expected.
"Both the telescope and instrument together produced unbelievably crisp images of very high quality that I am sure the FORCAST team will be able to go off and analyze and do some really good science in understanding these star formation regions we observed," she said.
The SOFIA missions looked at Orion, or M42, and S140, which are regions forming stars in the Milky Way galaxy. Also observed was nearby galaxy M82, which is undergoing a burst of star formation.
Those observations were conducted with the SOFIA telescope and the Faint Object Infrared Camera for the SOFIA Telescope, or FORCAST, instrument. The FORCAST was developed at Cornell University, Ithaca, N.Y. Using it on the SOFIA for the first time was an education with lessons that can be applied to future missions with the instrument, said Terry Herter, FORCAST principal investigator.
"We have learned quite a bit about how best to optimize the operation of FORCAST on SOFIA. Lab testing cannot fully reproduce the airplane environment," he said. "FORCAST and SOFIA are a system, which must be tuned together to get the best performance, and we have made great progress. This includes how fast to 'read out' [or, transfer data] the detector/sensor and synchronizing this with the observatory."
Nancy McKown, mission director for this series of SOFIA science missions, said preparation for the flights has been ongoing and included computer simulations and line operations - i.e., everything that would happen in the sky is practiced on the ground - prior to the first science mission.
The complex coordination tasks were directed by McKown, but a talented team worked together to met the flight objectives and built confidence and experience with the observatory, she said. The first flight included support from telescope operator Allan Meyer, who tallied 900 missions on the Kuiper Airborne Observatory, a SOFIA predecessor, and science flight planner Charlie Kaminski.
McKown, who also had experience on the KAO, said "the best training is in the air" and that with so few hours available, new people will be getting their first opportunity to fly on each flight whereas KAO operators had to have three to six months of experience before they could fly without direct supervision on board.
"What we are doing now is starting the science flights with the systems still in development," she said. "We are always mixing in something new, or fixing something from the last flight. It takes patience, but it is of benefit to us that we are helping to develop the observatory."
Evolving the systems also presents opportunities for enhancing procedures and working to mature the system. "It will never be static, it will always be dynamic," McKown said.
The SOFIA is fitted with a 100-inch-diameter airborne infrared telescope. The aircraft's instruments can analyze light from a wide range of celestial objects, including warm interstellar gas and dust of bright star-forming regions.
The program is managed at Dryden. The center also has responsibility for the NASA 747SP platform, which is based at the Dryden Aircraft Operations Center in Palmdale, Calif.
The SOFIA is an international collaboration between NASA and the German Aerospace Center, Deutsches Zentrum fur Luft und Raumfahrt (DLR).
SOFIA science and mission operations are managed at NASA's Ames Research Center, Moffett Field, Calif., in cooperation with the Universities Space Research Association in Columbia, Md., and the Deutsches SOFIA Institut at the University of Stuttgart, Germany.
By Jay Levine