I had fallen asleep while flipping through the channels on my hotel TV the night before, then when I finally woke up enough to take my contacts out and really go to bed, I couldn’t get back to sleep. I had too much on my mind. By the time I got back to sleep, it was after 3:00 a.m. and I had a hard time waking up when my alarm went off at 7:00. I slept in a little and went down for breakfast, then went directly to the 10:00 breakout sessions.
Quantum Computing and Machine Learning
I choose one on Exoplanet Detection Methods. The first speaker talked about using a DWAVE quantum computer (in a project jointly sponsored by NASA Ames Research Center, USRA, and Google). The DWAVE computer is very sensitive and has to be maintained in a Faraday cage, vibrationally isolated, and supercooled. It is able to use some of the properties of the legendary qubit – the quantum equivalent of a binary digit that uses multiple quantum states instead of merely ones and zeros. This computer isn’t a full quantum computer but is the first step in that direction. So far, they were able to use it to search through the Kepler data to better isolate signals from noise. It has been used on confirmed exoplanets to see if it could correctly identify the same signal, which it can. It will now be used on the upcoming K2 mission and the follow-up TESS mission, scheduled to launch in 2017.
The second speaker talked about using machine learning software to identify possible exoplanet signals, again filtering out the signal from the noise of the Kepler data. The machine learned how to categorize false positives versus astrophysical positives (such as eclipsing binaries or flare stars) versus actual exoplanets. Once it was able to correctly identify each type of signal at about 90% accuracy, it was used to analyze new data and has found 800 new potential exoplanets.
The third speaker talked about their technique to use a point-spread function to pull the signals from the noise, and how it improves detection by over 60%. They hope to be able to increase the sensitivity of this technique until it can identify planets around 12th magnitude stars.
This would have been very interesting under different circumstances but my sleep-deprived brain wasn’t taking it in, and my notes were becoming sparser and more illegible as I had trouble concentrating. I decided to move to a different session, which I had marked as my second choice.
The session I moved into was on exoplanet atmospheres. This is extremely intriguing to me, that the data we’ve gotten from Kepler can be massaged even further to pull out atmospheric details. I caught the end of one presentation on how narrow band filters applied to the Kepler data can be effective at detecting different elements in the planets’ atmospheres, such as potassium. They had looked at the planet GJ1214b, which seems to be a popular one here.
The next speaker discussed plotting the equilibrium temperatures of exoplanetary atmospheres and finding a gap around 1850°K, which the author interpreted as possibly a transition from cloudy to cloudless atmospheres.
One of the new things I’ve learned at this conference is that brown dwarf stars can actually have cool enough atmospheres for water clouds to form. A star with clouds on it. Another interesting fact is that we are finding fewer than expected brown dwarf stars – the vast majority of mass in the galaxy (about 75%) is tied up in red dwarfs. For exoplanets, most of the mass is in sub-Neptunian sized planets from 5 to 15 times the size of the Earth, not in Jupiter class planets. That means the distribution of mass in our galaxy is bimodal, for some unknown reason. Of course, we are only just beginning to find the Earth mass planets. Estimates range from 17-50 billion planets from 0.5 to 2.0 Earth masses in our galaxy. Of course, most of these will lie outside the habitable zone (HZ), but if even one out of five lie within, we could have 3-15 billion Earth-sized planets with liquid water. There’s got to be life out there somewhere.
Another presentation discussed looking at planetary atmospheres for systems with x-ray host stars. Since x-rays are produced in a star’s corona, as a planet passes in front of the corona the transit curve makes a W shape. Planetary atmospheres absorb x-ray energy, and as the corona passes behind the atmosphere’s limb (where the total amount of the atmosphere that the light has to pass through is thicker) it absorbs more light. Then, as the planet’s center passes, less atmosphere is passed through and the curve rises slightly, then dips again as the back limb of the planet passes in front of the star’s corona.
The next presentation discussed the atmospheres of hot Jupiters. I began to lose it again and my notes became more scribbled. I decided to head back to my room to check on my wife, who is stranded in Miami because of the bad weather (caused by a huge polar vortex descending over the Midwest). On the way, I ran into Wendi Laurence who is one of the NITARPers from this last year and a former Aerospace Education Specialist. She lives in Park City. She was talking to a man I hadn’t met, and she introduced him to me. He is Dr. Eric Hintz from Brigham Young University, who told me more about opportunities they have at BYU. He is here with two graduate students who are presenting. He also told me more about the summer research program for teachers I had read about. I will look into applying for that program, as it includes a stipend and I wouldn’t have to stay in campus housing – I could commute from home.
I got my wife’s hotel room and phone number and relayed information to people through her Facebook status and messaging. I’m not a big fan of Facebook, mostly because its interface is a useless jumble, but in this case it has come in handy to reach people in a way e-mail can’t.
NASA Astrophysics Town Hall:
I rested for a few minutes, then headed back downstairs. I attended today’s town hall meeting in the Potomac Ballroom A. Dr. Paul Hertz, whom I had met and spoken with on Sunday night, led the meeting and described the current and future plans for how NASA’s $1.25 billion astrophysics budget will be spent. At the beginning of each decade, NASA develops a Decadal Survey, which lists their top priorities for the next ten years. These include astrophysics, planetary science, and aeronautics priorities. Beyond the upcoming James Webb Space Telescope, which is on target for launching in October, 2018, priorities include a new mission for locating exoplanets. This will be after the K2 mission I heard about yesterday. It is called TESS: the Transiting Exoplanet Survey Satellite. There will also be a detailed all-sky survey in infrared to add to the WISE and 2MASS data.
Dr. Hertz also talked about the realities of the current lack of a finished budget and the uncertainties it puts into all planning. Because of sequestration and the partial government shutdown, this year’s entire season of balloon research from Antarctica had to be cancelled – the shutdown occurred at the worst possible time, just as the balloons were about to be shipped to the South Pole. Without the balloons, there could be no observations.
Today’s posters had an education and public outreach theme, and there were groups of high school students visiting various booths, such as using an infrared camera and a blow drier in the JWST booth. I looked around the poster sessions, which are divided into about five sections sandwiched between the exhibiter booths. The educational posters from the NITARP teams were up today, and I photographed them so that I could get a feel for what will be required of us.
I also looked at the booths in more detail, such as the Schott glass booth. They are the people that made the glass and backing for the primary mirror on SOFIA. They mill out most of the specialized glass, called Zerodur, leaving behind ribs to support the mirror. I heard later that they had special Schott shot glasses to hand out, but I missed getting one.
Detecting Gravity Waves:
One of the booths was for the new LIGO detector. It is the Laser Interferometery Gravitational Wave Observatory. Gravity waves should be produced by the large-scale sudden change in mass of a star or galaxy, such as in a supernova explosion. The waves, although weak, would propagate through the space-time continuum and cause large masses to move very slightly, and this can be detected (in theory). The idea is to suspend two large masses that are isolated from any incident vibration. Even a passing car would be too much. A laser would be split 90° and each beam would bounce off one mass, then come back together. If the masses remain motionless, the beams will add up constructively. If the masses move slightly because of any vibration, the beams will be out of phase and interfere with each other. They are building two facilities, one in Louisiana and one in Oregon, with a third planned for Australia or elsewhere. With three, they can triangulate a direction for incoming gravity waves.
I went to a talk session on education and public outreach, but had a hard time finding the room. When I got there, the room was small and overcrowded, so I had to sit on the floor by the door. It wasn’t what I had expected, and I did not recognize anyone there. Under the current budget proposal from the President, all EPO functions in any federal agency would be transferred to the Department of Education, the NSF, or the Smithsonian. It would effectively end all NASA EPO programs, including the one that brought me here and all the others I’ve been involved in. It is a huge mistake. I actually wrote letters and sent e-mails to all of Utah’s congressional delegation protesting this proposal. I’ll give the details of this in another post.
My legs were getting cramped, and my lack of sleep last night was catching up to me. I returned to my room and took a nap, then woke up about 6:00 and finished my blog post from the night before.
I was invited to dinner at a Mexican restaurant nearby with all the SOFIA people, including the Airborne Astronomy Ambassadors that could attend the conference. Most of us were NITARPers. The announcement of the new class of Cycle 2 AAAs is going to be tomorrow, and one team from Ohio was able to be here. I sat between Steve Jensen, the chief engineer for SOFIA, and Eddie Zavala, the program manager. The new team from Ohio was also at our table, as well as Theresa Paulsen (a Cycle 0 AAA) and her two students who were here for NITARP. We had a lively conversation, and I learned a great deal about the engineering challenges of SOFIA from Steve. I got his card so that I can ask more questions as they come up. I wish I could have recorded the conversation.
One story Steve told was of his previous work managing a pre-design team for the Orion crew capsule. In one meeting, he finally got the engineers and scientists to agree that they needed simple interfaces. This was the first thing they had ever agreed on. Steve stopped them and asked each group to clarify what they meant by “simple interfaces.” The scientists said they wanted touch screen controls that were intuitive to use. The engineers protested how hard and time-consuming it would be to make such controls, and that they weren’t simple at all. When Steve then asked the engineers what they had meant by a simple interface, they said, “A bolt!”
I am greatly impressed with the scientific, engineering, and management teams on SOFIA and their willingness to bring us educators in on the process, not as an afterthought but as an essential part of SOFIA. They’ve spent a great deal of engineering and planning to build the educators’ station on board, and Eddie puts in a great deal of time and effort to speak and work with educators. I feel like one of the team every time I meet them.
One of many things I learned at dinner is that the remaining three first generation instruments will go through final checkouts this spring. In the summer, SOFIA flies to Germany for a normal maintenance cycle, and then during the fall will be fully operational. The new AAAs will fly this spring.
I walked Mary Blessing back to her car. She lives in Virginia and had driven here for the dinner. She is another of the original six educators from Cycle 0. She dropped me off at the hotel, and I spent the rest of the evening catching up on e-mail, etc. I’ve met most of the Cycle 0 group now, with Cris, Mary, Theresa, and Peggy. Tomorrow we are to all be together for photo ops in the afternoon after the press release comes out. I hope to interview the other AAAs then. Eventually, my goal is to meet all of the AAAs. We are becoming quite a club.