NASA’s Airborne Observatory Targets Newborn Stars


(DING!) “The captain has turned off the safety lights – you are now free to explore the infrared Universe.”

Mounted inside the fuselage of a Boeing 747SP aircraft, NASA’s Stratospheric Observatory for Infrared Astronomy, or SOFIA, is capable of searching the sky in infrared light with a sensitivity impossible from ground-based instruments. Cruising at 39,000 to 45,000 feet, its 100-inch telescope operates above 99% of the atmospheric water vapor that would otherwise interfere with such observations, and thus is able to pierce through vast interstellar clouds of gas and dust to find what lies within.

Its latest discovery has uncovered a cluster of newborn stars within a giant cloud of gas and dust 6,400 light-years from Earth.

The massive stars are still enshrouded in the gas cloud from which they formed, a region located in the direction of Perseus called W3. The Faint Object Infrared Camera for the SOFIA Telescope (FORCAST) instrument was able to peer through the cloud and locate up to 15 massive young stars clustered together in a compact region, designated W3A.

SOFIA's 747SP on the ground at NASA's Dryden Flight Research Center on Edwards Air Force Base, CA. (NASA/Tony Landis)

W3A’s stars are seen in various stages of formation, and their effects on nearby clouds of gas and dust are evident in the FORCAST inset image above. A dark bubble, which the arrow is pointing to, is a hole created by emissions from the largest of the young stars, and the greenish coloration surrounding it designates regions where the dust and large molecules have been destroyed by powerful radiation.

Without SOFIA’s infrared imaging capabilities newborn stars like those seen in W3A would be much harder to observe, since their visible and ultraviolet light typically can’t escape the cool, opaque dust clouds where they are located.

The radiation emitted by these massive young stars may eventually spur more star formation within the surrounding clouds. Our own Sun likely formed in this same way, 5 billion years ago, within a cluster of its own stellar siblings which have all long since drifted apart. By observing clusters like W3A astronomers hope to better understand the process of star birth and ultimately the formation of our own solar system.

Read more on the SOFIA news release here.

The observation team’s research principal investigator is Terry Herter of Cornell University. The data were analyzed and interpreted by the FORCAST team with Francisco Salgado and Alexander Tielens of the Leiden Observatory in the Netherlands plus SOFIA staff scientist James De Buizer. These papers have been submitted for publication in The Astrophysical Journal.

SOFIA Reveals Star-Forming Region W40


Around 1957 light years away, a dense molecular cloud resides beside an OB star cluster locked in a massive HII region. The hydrogen envelope is slowly beginning to billow out and separate itself from the molecular gas, but we’re not able to get a clear picture of the situation thanks to interfering dust. However, by engaging NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA), we’re now able to take one of the highest resolution mid-infrared looks into the heart of an incredible star-forming region known as W40 so far known to science.

Onboard a modified 747SP airliner, the Faint Object infraRed Camera for the SOFIA Telescope (FORCAST) has been hard at work utilizing its 2.5 meter (100″) reflecting telescope to capture data. The composite image shown above was taken at wavelengths of 5.4, 24.2 and 34.8 microns. Why this range? Thanks to the high flying SOFIA telescope, we’re able to clear Earth’s atmosphere and “get above” the ambient water vapor which blocks the view. Not even the highest based terrestrial telescope can escape it – but FORCAST can!

With about 1/10 the UV flux of the Orion Nebula, region W40 has long been of scientific interest because it is one of the nearest massive star-forming regions known. While some of its OB stars have been well observed at a variety of wavelengths, a great deal of the lower mass stars remain to be explored. But there’s just one problem… the dust hides their information. Thanks to FORCAST, astronomers are able to peer through the obscuration at W40’s center to examine the luminous nebula, scores of neophyte stars and at least six giants which tip the scales at six to twenty times more massive than the Sun.

Why is studying a region like W40 important to science? Because at least half of the Milky Way’s stellar population formed in similar massive clusters, it is possible the Solar System also “developed in such a cluster almost 5 billion years ago”. The stars FORCAST measures aren’t very bright and intervening dust makes them even more dim. But no worries, because this type of study cuts them out of dust that’s only carrying a temperature of a few hundred degrees. All that from a flying observatory!

Now, that’s cool…

Original Story Source: NASA/SOFIA News. For Further Reading: The W40 Cloud Complex and A Chandra Observation of the Obscured Star-Forming Complex W40.

SOFIA Opens New Window on Star Formation in Orion

SOFIA’s mid-infrared image of Messier 42 (right) with comparison images of the same region made at other wavelengths by the Hubble Space Telescope (left) and European Southern Observatory (middle). (Credits: Visible-light image: NASA/ESA/HST/AURA/STScI/O’Dell & Wong; Near-IR image: ESO/McCaughrean et al.; Mid-IR image: NASA/DLR/SOFIA/USRA/DSI/FORCAST Team)

From a NASA Press Release:

A mid-infrared mosaic image from the Stratospheric Observatory for Infrared Astronomy, or SOFIA, offers new information about processes of star formation in and around the nebula Messier 42 in the constellation Orion. The image data were acquired using the Faint Object Infrared Camera for the SOFIA Telescope, or FORCAST, by principal investigator Terry Herter, of Cornell University during SOFIA’s Short Science 1 observing program in December 2010.
Continue reading “SOFIA Opens New Window on Star Formation in Orion”

SOFIA Telescope Makes First Science Flight


SOFIA, NASA’s airplane-based Stratospheric Observatory for Infrared Astronomy made its first science flight on Wednesday, to help demonstrate the aircraft’s potential to make discoveries about the infrared universe. The new observatory uses a modified 747 airplane to carry a German-built 2.5 meter (100 inch) reflecting telescope, and on its initial flight to gather science data, the plane flew for about 10 hours.

“These initial science flights mark a significant milestone in SOFIA’s development and ability to conduct peer-reviewed science observations,” said NASA Astrophysics Division Director Jon Morse. “We anticipate a number of important discoveries from this unique observatory, as well as extended investigations of discoveries by other space telescopes.”

SOFIA is anticipated to have a 20-year lifespan that will enable a wide variety of astronomical science observations not possible from other Earth and space-borne observatories.

Cruising at altitudes between 39,000 and 45,000 feet, researchers hope to study how stars and planets are born, how organic substances form in interstellar space, and how supermassive black holes feed and grow.

SOFIA is a 100-inch diameter infrared telescope, and the instruments can analyze light from a wide
range of celestial objects, including warm interstellar gas and dust of bright star forming regions, by observing wavelengths between 0.3 and 1,600 microns. A micron equals one millionth of a meter. For
comparison, the human eye sees light with wavelengths between 0.4 and 0.7 microns.

The first three science flights, phase one of SOFIA’s early science program, will employ the Faint Object InfraRed Camera for the SOFIA Telescope (FORCAST) instrument developed by Cornell University and
led by principal investigator Terry Herter. FORCAST observes the mid-infrared spectrum from five to 40 microns.

Researchers used the FORCAST camera on SOFIA during a test flight two weeks ago to produce infrared images of areas within the Orion star-formation complex, a region of the sky for which more extensive
data were collected during the Nov. 30 flight. The image below is of this region. You can see more images at this link.

This infrared image of the heart of the Orion star-formation complex was taken by SOFIA’s FORCAST mid-infrared camera. Credit: NASA

SOFIA flies from NASA’s Dryden Aircraft Operations Facility in Palmdale, California.

SOFIA Sees First Light


Flying SOFIA has opened her eyes! The Stratospheric Observatory for Infrared Astronomy (SOFIA), a joint program by NASA and the German Aerospace Center made its first observations on May 26. The new observatory uses a modified 747 airplane to carry a German-built 2.5 meter (100 inch) reflecting telescope. “With this flight, SOFIA begins a 20-year journey that will enable a wide variety of astronomical science observations not possible from other Earth and space-borne observatories,” said Jon Morse, Astrophysics Division director in the Science Mission Directorate at NASA. “It clearly sets expectations that SOFIA will provide us with “Great Observatory”-class astronomical science.”

Scientists are now processing the first light data, and say that preliminary results show the sharp, “front-line” images that were predicted for SOFIA. They reported the stability and precise pointing of the German-built telescope met or exceeded the expectations of the engineers and astronomers who put it through its paces during the flight.

Infrared image of Jupiter from SOFIA’s First Light flight composed of individual images at wavelengths of 5.4 (blue), 24 (green) and 37 microns (red) made by Cornell University’s FORCAST camera. A recent visual-wavelength picture of approximately the same side of Jupiter is shown for comparison. The white stripe in the infrared image is a region of relatively transparent clouds through which the warm interior of Jupiter can be seen. (Visual image credit: Anthony Wesley)

“The crowning accomplishment of the night came when scientists on board SOFIA recorded images of Jupiter,” said USRA SOFIA senior science advisor Eric Becklin. “The composite image from SOFIA shows heat, trapped since the formation of the planet, pouring out of Jupiter’s interior through holes in its clouds.”

Faint specks of starlight are reflected by the 100-inch (2.5 meter) primary mirror on SOFIA. Credit: NASA/Tom Tschida

Cornell University built the primary instrument on the telescope, the Faint Object infrared Camera for the SOFIA Telescope, also known as FORCAST. FORCAST is unique in that it records energy coming from space at infrared wavelengths between 5 and 40 microns – most of which cannot be seen by ground-based telescopes due to blockage by water vapor in Earth’s atmosphere. SOFIA’s operational altitude, which is above more than 99 percent of that water vapor, allows it to receive 80 percent or more of the infrared light accessible to space observatories, so FORCAST captures in minutes images that would require many hour-long exposures by ground-based observatories

Composite infrared image of the central portion of galaxy M82, from SOFIA’s First Light flight, at wavelengths of 20 (blue), 32 (green) and 37 microns (red). The middle inset image shows the same portion of the galaxy at visual wavelengths. The infrared image views past the stars and dust clouds apparent in the visible-wavelength image into the star-forming heart of the galaxy. The long dimension of the inset boxes is about 5400 light years. (Visual image credit: N. A. Sharp/ NOAO/AURA/NSF)

The first light flight took off from SOFIA’s home base at the Aircraft Operations Facility in Palmdale, Calif., of NASA’s Dryden Flight Research Center. The in-flight personnel consisted of an international crew from NASA, the Universities Space Research Association in Columbia, Md., Cornell University and the German SOFIA Institute (DSI) in Stuttgart. During the six-hour flight, at altitudes up to 35,000 feet, the crew of 10 scientists, astronomers, engineers and technicians gathered telescope performance data at consoles in the aircraft’s main cabin.

More info on SOFIA.

Source: NASA

The Story Behind SOFIA, NASA’s Flying Observatory


From the Cornell University Chronicle, written by Lauren Gold:

The SOFIA project has been in the making for more than 13 years — but the airplane has an even longer history. Originally owned by Pan Am, the 747SP (Special Performance) was named the Clipper Lindbergh and christened by Anne Morrow Lindbergh in 1977 on the 50th anniversary of Lindbergh’s flight across the Atlantic.

The Boeing 747SP differs from a modern 747 in a few ways. Most notably, it’s 45 feet shorter and, thus, lighter — which allowed it to make long transoceanic flights without stopping to refuel. (Modern 747s have much more efficient engines.)

The plane already had two Cornell connections long before astronomy professor and principal investigator Terry Herter and his team installed FORCAST onto the telescope in February.

When Boeing was designing the plane in the 1970s, they hired a young Cornell mechanical engineering graduate to design its horizontal stabilizer (which allows the pilot to raise or lower the nose of the plane in flight). That engineer, Bill Nye ’77, eventually went on to become “Bill Nye the Science Guy” — the Emmy Award-winning science educator and Cornell Frank H.T. Rhodes Class of 1956 Professor from 2001 to 2006.

A decade later in 1989, when the plane was in commercial service, George Gull, Cornell research support specialist and now lead engineer for FORCAST, just happened to notice the “Clipper Lindbergh” insignia on his plane when he flew from Hong Kong to San Francisco after a Cornell Glee Club trip to China.

So while Gull won’t be one of the lucky few on the plane for the May 25 first light flight — he can boast having flown on the plane 21 years before everyone else on the team.

Since NASA bought the Clipper Lindbergh in 1997, SOFIA has undergone more than a few changes. Among many other things, it has a 16-by-23-foot door cut into the port side for the telescope and a bump near the rear of the plane that smoothes out airflow around the fuselage when the telescope door is open.

Currently, a grid of what looks like hundreds of small dots — actually pieces of yarn — cover the surface of the telescope door and the area around it. The yarn is a low-tech but effective way of optimizing aerodynamics — researchers flying alongside SOFIA in a chase plane videotape the yarn’s motion to analyze air flow around the door. The yarn will be removed when the observatory goes into regular operation.

Inside, the plane has a few remnants of its past: several original seats; the spiral staircase to the upper deck; an array of analog instruments in the cockpit. But most of the seats are a hodgepodge of military airplane seats at workstations, facing backward toward the massive, 17-ton telescope and instruments.

The cabin also includes an area for educators and reporters who will take part in flights as part of the mission’s effort to educate and engage the public. And the telescope itself is part of a pressure bulkhead that allows the main cabin to stay pressurized despite the open door behind it.

Despite its novelty, SOFIA follows a long history of airborne astronomy that started with observations made from biplanes in the 1920s and ’30s. Most recently, NASA’s Kuiper Airborne Observatory, a modified Lockheed C-141 with a 1-meter infrared telescope that operated 1974-95, was the vehicle for discoveries including the rings around Uranus, the atmosphere around Pluto and the presence of water vapor in the interstellar medium.

Source: Cornell

Airborne Observatory Passes Next Stage of Testing

If you’ve ever been out observing and the clouds roll in, undoubtedly you’ve thought, “If I could only get above all of these stupid clouds, the sky would look great!” Well, NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) is capable of doing just that: SOFIA is an infrared telescope mounted on a 747SP airliner that used to be a passenger plane for Pan Am. By mounting the telescope on an airplane, NASA is able to fly it into the stratosphere, and get past all of the annoying gases and water vapor that get in the way when making observations.

SOFIA is still undergoing a battery of testing to ensure proper operation of the telescope before it starts observations. In December of last year, the telescope was taken up and the doors to the bay where it is mounted were opened. On January 15th, the telescope was flown to 35,000 feet (10.6 km) and the doors were left closed to test an updated gyroscope that was installed on the ‘scope.

These latest tests were designed to test how well the telescope can stabilize itself, because an airplane flying at 41,000 feet (12.5km) – the altitude at which many observations will be made – isn’t exactly a steady mount for a telescope. Gyroscopic stabilizers counteract the movement of the airplane to steady the telescope for observation.

During the test, the ability of the entire system to operate at cooler temperatures was established as well. The temperature for this latest test hovered around -15 degrees Celsius (+5 degrees Fahrenheit) even with the doors closed.

The telescope itself has a 2.5 meter (8.2 foot) mirror, with a 0.4 meter (1.3 foot) secondary mirror. The range of wavelengths that SOFIA can “see” is 0.3 microns to 1.6mm, meaning it’s capable of taking images in the infrared and submillimeter.

Some of the objects and phenomena that SOFIA will be observing include proto-planetary disks and planet formation, star formation, the chemical composition of other galaxies and interstellar cloud physics. An extensive description of SOFIA’s capabilities can be found on their site here.

SOFIA still has a few tests to undergo, and will be fully operational come 2014. In the next few years basic science observations will start up, and then other instruments will be added to the observatory. SOFIA is a collaboration between NASA and a German telescope partner, Deutsches SOFIA Institute.

Source: NASA press release