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Stardust Adventure

Jim Albers


 

“ Peter ... surprised me by saying that one of the investigators wasn't going..., so I was welcome to come along!”

 

The crew in a picture taken before a practice flight. Photo courtesy of NASA.

 

My Stardust adventure started Dec 15th when I sent an email to SJAA president Mike Koop inquiring about the reentry trajectory to find out where it might be possible to see it. He's participated in many meteor observing campaigns with Peter Jenniskens, of the SETI Institute, and flew on the aircraft to observe the Genesis reentry in Sep, 2004. Amazingly, they had just received their first Stardust Reentry Capsule (SRC) trajectory. He also said that they were looking for some help to coordinate ground observations as a complement to the planned observations from the DC-8 aircraft. I tentatively agreed, not quite sure what I what signing up to. I exchanged some emails with Mike and Peter, created some finder charts using Skymap for a few locations and made a short presentation at the beginning of the Dec 17th SJAA meeting. Peter and I then talked for most of that meeting about how to get the general public and amateur observers interested in taking photos and videos. At some point during the meeting, I decided to take on the challenge.

I created a first update of the NASA Ames/SETI Viewing Forum web page the next week. My girlfriend Diana was instrumental in having a web page that had a non-technical introduction and lots of instructions, and didn't immediately go off into topics that only some of us might appreciate. We also contacted the Night Sky Network and Jane Houston Jones to help get the word out to astronomy clubs in the reentry area.

Fortunately I had extra time between Christmas and New Years. I generated a ground track of where the SRC would pass in front of the Moon, as Peter was interested in how the hot wake behind the SRC developed and the Moon would be a good backlight. I learned a lot about the software program I was using to generate the ground track. I was starting to get Viewing Forum Observing Intent emails, some of which included questions and did my best to answer the questions and generate finder charts for those that needed them. I then created my own web page so that all the plots and data that I had been generating could be easily accessible and Peter didn't need to spend so much time away from flight preparations to update his web page. At some point, the idea of using Iridium flares as a test came up as they are very bright transitory events similar to the reentry, so I generated predictions for the nights of the test flights using the Iridflar program. There were flares around 6 p.m. and 6 a.m. every day.

After the New Year, the team wanted an independent analysis of the aircraft observing conditions to have the highest probability of observing the reentry, so I started working with Dean Kontinos of NASA Ames to analyze alternate aircraft viewing locations in case of cirrus clouds and variations in the reentry trajectory.

A news conference was scheduled for Jan 11th, at NASA Ames and we were also planning to have a meeting of the ground observers. Journalists were invited to apply to fly on the rehearsal flights or the reentry flight. I applied as a reporter for the SJAA Ephemeris and for my company newsletter, but never received a response. There was a good turnout of TV, radio and print journalists at the news conference, and I talked to a number of them about getting the general public to observe the reentry and gave them handouts with our URL. Ron Dantowitz and Marek Kozubal from the Clay Center Observatory were also there with their automated tracking telescope. Peter Jenniskens was very busy with the journalists and helping prepare for the flight.

After many of the journalists left, I went into the DC-8 observing aircraft to look around. On both sides of the aircraft are several rows of large comfortable seats alternated with storage boxes, bolted down equipment, and clear areas with instrument mounts on the windows. I was asked to update the aircraft navigator for the time and location of the Iridium flare. It suddenly occurred to me that a planeload of people were all going to be depending on my predictions being correct. Peter was going to give the printouts back to me, and I said he should just keep them unless I was going on the flight. He then surprised me by saying that one of the investigators wasn't going, I had applied for a flight and had been helping out, so I was welcome to come along!

Suddenly I had to go to safety and flight briefings and needed to fill out a "next of kin" form. At the flight briefing, Peter introduced me as the person to thank if the Iridium flare took place as predicted and the person to blame if it didn't. It was quite an introduction to the group. I then rushed off to pick up a few things from home and grab some food for the plane, as I had never had time for lunch. When I returned, a flightsuit was found and I quickly put it on before the doors were shut and we had to be in our seats. Everyone had headsets to help keep the plane noise to a minimum and so that everyone could communicate.

We took off at 5 p.m. to the North and gained altitude over the Bay Area, as the sun was setting through scattered clouds. The view out the window was quite nice. I finally got to eat my lunch as each of the groups responsible for a given instrument were cleared to setup and start checking their equipment one by one. Everything had to be packed up in the large storage boxes for takeoff and landing, and then looked at by a member of the flight crew after it had been setup. After a while, the cabin lights were turned out. It was darker than before, but it certainly wasn't like amateur observing from a dark site as the cabin was filled with bright video monitors and computer screens. That's modern astronomy.

Everyone was pretty much ready before the Iridium flare over Monterey at 6:02 p.m. We got some notification of it occurring, but I had to take off my headset in order to look out the window on the opposite side of the aircraft. I watched the time indicator on my GPS and waited. Right on time, the flare showed up where predicted, thank goodness. I then walked around a bit and found that most instruments had captured the flare and watched some video of it taken by one of the cameras.

We then started a "racetrack" pattern over the Pacific off the central coast of California. The pattern had two straight sides and two 180 degree turns so that the instruments could be aligned and checked out and the operators could get experience pointing them at stars and the Moon. I went around the cabin trying to watch what was going on and stay out of the way.

One of the first things the team learned on this first test flight in the cold air at 39,000 ft. was that the air tubes that kept the windows from fogging up needed to be reoriented. Most teams solved this problem by adjusting the tubes themselves, but a couple would require further adjustment after the flight. I helped a bit by loaning out my flashlight for most of the flight, and Mike Koop and I pointed out stars and constellations to the astronomers just like at a star party. Mike let me put on the video goggles he used for pointing the Eschelle spectrometer. I practiced tracking stars and kept an eye on the computer monitor to see if I was actually tracking well enough to capture spectra. It wasn't easy when the target was moving due to the plane turning, turbulence, etc. You're down on your knees, and the instrument gets heavy after a while. I was glad I didn't have to be the one following the SRC as it went by.

Pretty soon it was time to pack everything up for landing. The light sensitive instruments were shut down, the cabin lights were turned back on, everything was put back into the storage boxes, and we strapped back into our seats. A flight briefing was held as we headed back home. Not everything was perfect, but it was a successful first rehearsal. We landed back at Moffett after being in the air for 3 hours, and I headed home. It's the only time I've ever been happy about returning to the same airport after flying around for 3 hours. Some of the scientists were planning to come back and work after a short dinner break.

My friend Bryan and I wanted to be in Eastern Nevada to see the brightest part of the trajectory, but the weather was starting to look like it wasn't going to cooperate. We ended up driving to Reno on Friday and then back over the Sierra Nevada Mountains in the snowstorm on Saturday to observe the reentry from Redding. Thanks to my girlfriend Diana working as our informal travel agent, we stayed in hotels that were easy to get the equipment in and out of and had Internet access. That way I could continue helping with the analysis to account for changes in the trajectory due to the last couple of maneuvers and we could watch the weather.

It was cloudy in Redding when we arrived and we couldn't really find a very good site after driving around for a while. After dinner it even started to rain slightly, so I was thinking we could always watch the reentry on NASA TV on the Web. I actually did have some faith in the weather predictions, and sure enough, about 8:30 I went outside to check and saw the Moon and a virtually cloud free sky full of stars, so felt very relieved and Bryan and I were able to take some test stills and video.

On the way to our observing sight, we came upon a clearing on the side of the road up on a hill with a good view to the North and NE, so we setup there. We had WWV reception for a while but then it dropped out, so I had to keep watching the GPS to keep track of time, which at 2 AM after driving for 2 days, I didn't do very well. We were both watching to the NW of Polaris, hoping to see the SRC as soon as possible. Fortunately Bryan noticed it as it appeared just East of Polaris, and we quickly swung our cameras over to follow it. I was able to get about 20 seconds of video on 2 cameras and Bryan took a number of digital stills. We were able to follow it down to just a few degrees above the horizon, where it disappeared into the clouds. This was surprising as most of the brightness was expected to be due to heating on the front of the SRC and by that point we were pretty much looking at the back of it and through a whole lot of atmosphere. More recent photometric analysis of the video confirmed our impression of the brightness over time that night.

We went back to the hotel, Diana helped me get a number of the observations posted to the Web, watched the recovery, got a few hours sleep and drove home. While our personal observing had not gone as well as it could have, I was pleased that I had made a valuable contribution to the Stardust reentry observing campaign.

Since then we've received a number of photos and videos from our observers and I've gotten copies of some of the video from the aircraft and

have done some more analysis. I've been digitizing the videos, creating light curves from the video frames and learning a lot about video CODECs. I've also been registering long exposure photos with the trajectory and stars so that light curves can be derived from the photos. Both are also being analyzed to compare SRC position to predictions. It continues to be an engaging and challenging project that fills my free time.

My Stardust Web Page: here.

Photos of the DC-8 aircraft the day of my test flight taken by Bryan Murahashi.

Peter Jennisken's Reentry page.

The Viewingforum page that I updated.

 


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