The Stratospheric Observatory for Infrared Astronomy (SOFIA) was a mission of discovery, revealing unseen — and sometimes unseen — parts of our universe.
As the mission draws to a close with the final flight ending September 29, NASA looks back on SOFIA’s scientific accomplishments and some of the engineering feats that made it possible to fly.
“From deepening our understanding of water on the Moon to revealing the invisible forces of magnetic fields on a cosmic scale, none of this could have happened without the hundreds of people who contributed their expertise. to the SOFIA mission,” said Naseem Rangwala, the mission’s project. scientist at NASA’s Ames Research Center in California’s Silicon Valley.
From the start of its development in 1996, SOFIA required engineering ingenuity. A Boeing 747SP airliner had to be modified to carry the 38,000-pound, 100-inch telescope provided by NASA’s partner on the SOFIA mission, the German Space Agency at DLR.
Ames engineers developed a garage door-like mechanism that rolled up to allow the telescope to observe the sky. In this configuration, it was “one of the largest open ports ever flown on an aircraft,” said Paul Fusco, a now-retired NASA engineer who helped design the door system. , “and the largest certified to fly at all altitudes and speeds. with the door open. It was a truly exciting aeronautical innovation.
The mission pilots couldn’t even sense when the door was open. And the stability of the telescope itself was equivalent to keeping a steady laser pointer on a penny 10 miles away. SOFIA had achieved a smooth flight and a steady gaze.
And that was only the beginning. By 2014, the observatory had reached full operational capacity, and for eight years SOFIA has helped astronomers around the world use infrared light to study an impressive number of cosmic events and objects invisible to other telescopes.
“SOFIA’s unique scientific achievements are the result of the ingenuity of the incredible international community that has grown up around the mission,” said Alessandra Roy, SOFIA Project Scientist for the German Space Agency, “who n was only made possible through the collaboration of NASA and DLR. .”
A community of high school teachers also got to know SOFIA personally, thanks to NASA’s Airborne Astronomy Ambassador program. This professional development opportunity included an immersion experience aboard SOFIA with scientists and crew members. Participating teachers were able to bring this real-world science content back to their classrooms and reveal various STEM-related careers to students.
Today, the observatory is being removed. Science flights have been completed and the team is investigating options for permanent accommodation suitable for this special aircraft. SOFIA’s data from a total of 732 nights of observation during the mission will also be publicly available for scientists to study and conduct further research in the future.
“Infrared astronomy will continue at NASA, including with the James Webb Space Telescope,” said Paul Hertz, senior adviser to NASA’s Science Mission Directorate, former director of the Astrophysics Division and former program scientist. SOFIA. “But SOFIA’s many and diverse contributions to science have already left their mark.”
Here are some ways SOFIA has changed our understanding of the universe.
Discovery of water on the sunlit part of the Moon
Although SOFIA’s telescope was not originally set up to look at the Moon, its lunar observations confirmed, for the first time, the presence of water on the Moon’s sunlit surface. This meant that water could be distributed over the entire lunar surface, and not limited to cold, shady places.
NASA is eager to learn more about water on the Moon before sending humans to the lunar surface with the Artemis missions. Data from SOFIA also adds to the work of future lunar missions, such as NASA’s Volatiles Investigating Polar Exploration Rover.
The Moon was not SOFIA’s only target in our solar system. The observatory has also studied the circulation of gases in Jupiter’s atmosphere, the possibility that comets deliver carbon to planets like Earth and, most recently, the asteroid which will be explored by NASA’s Psyche mission, to name a few.
Finally detected: first type of molecule to form in the universe
After decades of research by astronomers, SOFIA has detected, for the first time in space, the first type of molecule to ever form in the universe.
SOFIA’s work in astrochemistry has also shed light on how water is distributed in the universe. The mission also explored the life cycle of materials in space: clouds of simple gases that form more complex gases and, ultimately, stars and star systems.
SOFIA’s mobility has allowed it to capture extremely fleeting astronomy events in remote locations.
In 2015, Pluto passed directly between a distant star and Earth, giving scientists a rare chance to analyze its atmosphere backlit by the star. And the only observatory that could position itself over the open ocean, directly in the center of Pluto’s shadow crossing the Earth’s surface, was SOFIA.
SOFIA was nimble, which also helped it provide long-term monitoring – such as a surprisingly long and bright protostar outburst in the Cat’s Paw Nebula – and react quickly, when needed. Such was the case in 2014 when an explosive star, a supernova, was spotted – the brightest and closest to Earth in decades.
Reveal the magnetic universe
Perhaps SOFIA’s most revolutionary contributions have been to allow astronomers to “see” and map magnetic fields at smaller scales than ever before.
Magnetic fields, once thought to slow star birth by preventing gravity from pulling raw material into a growing star, can sometimes work with gravity to nurture star birth, a study has found.
SOFIA has studied the roles that magnetic fields play in the cosmos at different scales – from star formation on the “small” end to phenomena shaping entire galaxies, powering black holes and causing entire galaxies to merge.
A new way to study the Earth’s atmosphere and climate
Flying between 38,000 and 45,000 feet, SOFIA hovered above 99.9% of the water vapor in Earth’s atmosphere, which obscures infrared observations from the ground. But the telescope was still looking through the heights of our atmosphere.
After developing ways to work with SOFIA data on this difficult-to-study region, the researchers were able to make direct measurements of atomic oxygen in Earth’s upper atmosphere.
Studying other atmospheres was already in SOFIA’s wheelhouse. Observation of a star’s occultation by Neptune’s moon Triton has revealed the secrets of its atmosphere, while a set of thought-provoking sightings of Venus could help shed light on phosphine reports, a potential biomarker of microbial life in the atmosphere of this planet.
A star is born — or not
By observing in infrared light, SOFIA has revealed secrets of star formation that would otherwise have remained hidden inside huge clouds of gas and dust.
One of SOFIA’s main areas of research involved an effect called “feedback,” where stars help or hinder the creation of more stars in their vicinity. Using data from SOFIA, the researchers found that a stellar wind in the Orion Nebula clears a bubble without matter needed for new star formation, while in another nebula the original star triggers the birth of new generations.
Astronomers learned all of these things and more as SOFIA explored the universe at 40,000 feet. Even as the mission draws to a close, paving the way for the next chapter in infrared astronomy, the discoveries made from the observatory’s data will continue. SOFIA’s legacy and that of the entire team that flew the mission is to have taught humanity more about the cosmos and inspired others to do the same.
SOFIA was a joint NASA and German Space Agency project at DLR. The DLR provided the telescope, scheduled aircraft maintenance, and other support services for the mission. NASA’s Ames Research Center in California’s Silicon Valley managed the SOFIA program, science, and mission operations in cooperation with the Space Research Association of Universities, headquartered in Columbia, Maryland, and the German SOFIA Institute at the University of Stuttgart. The aircraft was maintained and operated by NASA’s Armstrong Flight Research Center Bldg. 703, in Palmdale, California. SOFIA reached full operational capability in 2014 and concluded its last scientific flight on September 29, 2022.