SOFIA Captures a Speeding Shadow


By Brent Cobleigh

SOFIA Platform Project Manager
On June 23, the SOFIA returned from a mission that the principal investigator, Ted Dunham, called “gutsy.” As a star passed behind Pluto, a faint shadow passed over the Earth at a speed of 51,000 mph. The 100km-wide shadow passed over remote areas of the Pacific Ocean, out of the view of most ground-based observatories. The SOFIA’s unique ability to carry our 17-ton telescope to an altitude three times higher than the world’s best ground-based observatories is one of the reasons this program exists. Here is a quote from Ted:


“Occultations give us the ability to measure pressure, density and temperature profiles of Pluto’s atmosphere without leaving the Earth, which is 3 billion miles away from Pluto. Because we were able to maneuver SOFIA so close to the center of the occultation, we observed an extended, small but distinct brightening near the middle of the occultation. This will allow us to probe Pluto’s atmosphere at altitudes lower than usually possible with stellar occultations.”

The Pluto Occultation Mission was performed with the High-Speed Imaging Photometer for Occultation instrument, which is specifically designed to maximize science collection during an occultation. The photometer is the third science instrument integrated onto the aircraft this year. And we also started flying the water-vapor monitoring system back in March.

The Pluto success comes on top of finishing the first competed flight phase, Basic Science 1 – or BS1 – a few weeks ago. I checked a schedule that we made back in November, to see how close we were to finishing the BS2 flight phase as planned, and we finished one day early! Developing and testing the SOFIA has been a huge challenge, but the hard work is paying off.

And the year is not over. We expect to start the BS2 flight phase in July. After that, we will start testing the liquid nitrogen pre-cooling system that will chill the telescope mirrors prior to takeoff so that we don’t have to waste valuable flight time waiting for temperatures to stabilize. We also have enhancements to test that will improve the telescope pointing accuracy, and a goodwill deployment to Germany in September. The team is developing systems for the segment 3 downtime scheduled to start in November. Completing, installing and testing all the new and upgraded systems will be another challenge that will require the diverse skills of the Platform Project team.

On June 24, I was notified that SOFIA was selected to receive a NASA-wide group achievement award for the Initial Science Flight that we successfully completed last November. Congratulations to the whole team.

My job satisfaction is always based on two things: achieving an ambitious goal, and working with an excellent team. So I am glad to have this job because it allows me to achieve both. Though I’ll be the first to admit that there are ups and downs from day to day, the bottom line is that we are executing what we planned and fulfilling our promises to the science community and to the public. Like many ambitious projects, there are 10 hectic days for every day available to reflect on our success (sometimes it feels like 100 to 1). From time to time, step back and realize the progress we are making.  

Many thanks to SOFIA team members for their hard work and dedication.

A Great Day to Go Flying

By Mike Holtz
NASA Project Lead, Operations/Flight Test Engineer
Weather was on the warm side as we prepared for another mission in NASA F/A-18 #852 testing the Mars Science Laboratory landing radar, but it was still a great day to go flying.  

After intensive and lengthy ground operations on the order of an hour in the aircraft, we taxied out for our flight. We climbed up to 48,000 feet altitude and lined up for the first series of dives. We flew dive angles at 20, 30, 45 and 60 degrees.

Image right: NASA research pilot Nils Larson, left, and Mike Holtz review flight test cards before a test mission in an F/A-18.

The MSL radar within the QTEP – Quick Test Experimental Pod – was set to run several different gimbal angles, some locked and some actively slewing, all with the intent of radiating off the lakebed in some combination with the dive angles from the F-18. All but one test point on the flight cards was achieved before we hit our “bingo,” or minimal fuel remaining, and we had to land. The radar was developed by NASA’s Jet Propulsion Laboratory, and the JPL engineers were very happy with the flight. The radar engineers said the data looked fantastic.  

A very good mission, plus I’m pretty sure I lost 5 pounds sweating in the cockpit!

Shaking Hands With A Hero

By Don Johnson
Deputy Project Manager
Ikhana UAS
As part of my job supporting NASA, I recently gave a short presentation to a committee doing an assessment of Dryden Flight Research Center, where I work. I work on the Ikhana – a modified Predator B unmanned aircraft system – and that is what my presentation was about. A couple of the key people with whom I work were on business travel that week, so the duty to make the planeside presentation fell to a couple of other team members and me.

This was a tour of Dryden’s aircraft and capabilities, so the committee received numerous briefings during the afternoon as they toured from hangar to hangar. Now, this committee is part of the Aeronautics and Space Engineering Board of the National Research Council. In other words, a typical government bureaucracy – well, maybe not so typical. The committee is made up of a bunch of high-roller VIPs from places like MIT, Georgia Tech, Lockheed-Martin, Boeing…really BIG brains, about 15 of them, plus several local Dryden managers.

Now flash back to when I was but a lad, not yet 15 years old. I would sit, mesmerized, in front of our little black-and-white TV, watching Walter Cronkite talk about the major milestones and big events of the American space program – yep, NASA. Then, on July 20, 1969, the first human uttered the words, “That’s one small step for man, one giant leap for mankind.”

I was 14 years old that day, attending the Boy Scout National Jamboree at Lake Pend d’Oreille in Idaho along with about 50,000 other Boy Scouts from around the country. Somehow, the scouting organization managed to create some kind of giant big-screen projection system so that we – all 50,000 of us – could watch that first moon step in real time. Remember, this was 1969 – amazing! That event in history, that first step, will be remembered for as long as there is history and there are people to remember Apollo as one of humanity’s greatest accomplishments.

In addition to the big-screen presentation, the guest speaker on the night of this Boy Scout gathering was astronaut Frank Borman, the commander of Apollo 8. That was the mission in 1968 that first orbited the moon (no landing), the mission on which astronauts read from the book of Genesis on Christmas Eve. He arrived at the outdoor theater right next to where I was sitting on the grass. I think I still have the picture I snapped of him while he was standing there waiting to go onstage.

Well, living through these special events made quite an impression on a young lad, and set the direction of my life for the next 45-plus years. Years later, I became an aerospace engineer, and went to work for the Air Force at Edwards Air Force Base. By the time I graduated in 1977, the Apollo program was over and NASA was drawing down – kind of like the same situation as now due to the space shuttle program coming to an end. There is only one shuttle launch left to go, after which our astronauts will get to and from the space station on Russian spacecraft. After 32 years with the Air Force, I retired and went to work for Tybrin Corp., supporting…NASA. Well, that’s pretty cool!

Back to the present. If you haven’t guessed by now, it turns out that one of the members of this committee of 15 Big Brains hired to assess Dryden capabilities in 2011 was indeed that same first human to step on another heavenly body – the moon – in 1969: Neil Armstrong. He is STILL in the aeronautics business! I had the honor of telling him about our little Ikhana project, and then he and some other committee members asked us a few questions. After the briefing ended, Neil Armstrong immediately stood up and came over to the three of us who had just briefed and shook our hands, thanking us for the presentation, then quietly moved on to the next set of briefings.

There aren’t many people in this world that I consider a hero. He is one of the very few.

Some days, it really pays to get up in the morning!

Image: Ikhana deputy project manager Don Johnson (at right in tan shirt) is among listeners as Ikhana lead operations engineer Greg Buoni briefs members of the National Research Council Aeronautics and Space Engineering Board during a visit to NASA Dryden. Apollo 11 astronaut and first man on the moon Neil Armstrong (in white jacket) is seated at left.

All In A Night's Work

By Beth Hagenauer
Dryden Public Affairs
I settled into my assigned seat for the 10-hour journey. The red-eye flight would cross 11 states, eventually reaching an altitude of 44,000 feet and traveling 4,700 miles. The ticket price was very good – it came as part of my job as a public affairs media escort for a prestigious documentary crew.

As the aircraft lifted off at dusk from the Air Force Plant 42 runway in Palmdale, Calif., I realized this would be no ordinary 747 flight; I was aboard the SOFIA, or the Stratospheric Observatory for Infrared Astronomy, a flying astronomy observatory.

SOFIA is the airborne platform for a joint program between NASA and the German Aerospace Center DLR. The program is based at NASA’s Dryden Aircraft Operations Facility in Palmdale. To modify the 747 for its new role, a 16-foot-high hole has been cut in the aircraft’s port side and a one-of-a-kind infrared telescope installed in the opening. Most of the former airliner’s trappings – seats, food-preparation galley and movie screens – have been removed and replaced with workstations equipped with computers and sturdy passenger seats with five-point seat-belt harnesses.

Image right: Terry Herter, principal investigator with the FORCAST instrument, takes a minute during a SOFIA flight to explain a concept to a visiting television crew.

The television film crew was aboard to record the science mission; their viewers who have a working knowledge of astronomy are familiar with ground-based telescopes and satellites, but an aircraft carrying a telescope brings a different dimension to studying the solar system. The usual flight crew was on tap for the mission, but so was a gaggle of German and American scientists and telescope operators who had planned a flight route that would take us to observation points for targets with names like Alpha Boo and Frosty Leo – the latter, I learned, a dying star. The 17-ton German-built telescope sports a Cornell University instrument called FORCAST, which is an acronym for Faint Object Infrared Camera for the SOFIA Telescope.

As soon as the “Fasten Seat Belt” sign was turned off, the science crew took their stations at consoles outfitted with computer screens to begin their night’s work. About an hour into the flight, the exterior door covering the telescope cavity was opened. White dots of varying sizes surrounded by colored boxes and text that seemed to be astronomers’ code began to appear on the computer screens. The aircraft is very noisy, so all communication was via headset. One of the mission director’s tasks is to monitor scientists’ conversations and transmit information to and from the pilots if necessary – say, for changes to the flight plan that might mean getting a better look at a target.

About three hours into the flight, I went upstairs to the cockpit. More than 500 tiny lights illuminated a variety of circuit breakers and gages; the SOFIA cockpit is original technology and has not yet been upgraded with a “glass” cockpit, the current standard in modern aircraft. Looking out of the windows, I saw a sea of clouds lit by the full moon. It was easy to see stars with the naked eye – or visible light, as the astronomers refer to it – in the dark sky.

Unlike the environment in the main cabin, the cockpit was quiet except for occasional radio transmission between the NASA 747 and Federal Aviation Administration air traffic controllers in Seattle.

The most auspicious passenger was a small stuffed koala mascot that had flown more than four million miles on SOFIA’s predecessor, NASA’s fabled Kuiper Airborne Observatory. Earlier this year, the bear had been passed, along with the astronomical-research torch, from one generation of NASA scientists to the next.

Image below: Beth Hagenauer takes her seat in NASA’s newest airborne observatory, the SOFIA.


As the flight progressed the scientists continued their work, the adrenalin rush that comes from collecting real-time science data keeping them awake. (It had to have been that, because there was no hot coffee anywhere on board.) A flight on SOFIA is literally the only opportunity astronomers get to conduct their work in a shirtsleeve environment.

And my impression? Not being an astronomer by training, I still found myself in awe of the telescope. I never tired of watching its slow and precise movements, knowing that this activity replicates a tilting of the telescope mirror that was “peering” at the stars from within its specially designed cavity.

I brought my own dinner, since not even the dreaded “airline food” was available. I put my coat on when the aircraft reached 44,000 feet. Above all, I was tired when the aircraft landed at dawn back in Palmdale. As I watched SOFIA being towed back into the hangar and sent a very happy film crew on their way, I was reminded of a phrase that I’ve heard NASA colleagues say many times: “…and they pay me to do this?!”