On Wednesday, Jan. 8 I spent the better part of the day in the Exhibit Hall looking at posters. I had intended to visit several of the breakout sessions, but the posters today were mostly on exoplanets, young stellar objects, and astrobiology, topics that I am particularly interested in. I found that I could understand the research questions and conclusions better overall than on previous days. It was like a prospector following a rich vein of ore – you don’t abandon a good vein to go prospect elsewhere. So I stayed with the posters because I was learning a great deal.
Posters of Note:
One of the first posters I encountered was of the two students from Brigham Young University, who detected pockets of water around YSOs that are acting as natural masers (microwave lasers) that focus microwave light from the YSO into coherent beams.
Luisa’s own poster was right next to his. She was looking at the rate of variation of YSOs over timescales of years. This requires frequent observations of the same area of the sky over several years to observe how the stars change over time.
Several of the NITARP student groups presented their posters today, since their projects were related to YSOs. Conner Laurence from Park City presented with John Gibbs’ students and others. Their project looked at protostars forming in a bright-rimmed cloud called BRC 38 along the edge of IC1398, a stellar nursery. Central young O and B stars are blowing away the center of the nebula, leaving a bubble of cleared space. Around the edge of this bubble, denser globules are not evaporating from the stellar wind of these central stars. Inside these globules, new stars are forming but are only visible in infrared. Getting a spectral energy distribution curve (SED) can determine if the protostars still have disks or rings of material around them where planets could be forming. The students had discovered five new protostars within BRC 38 that were previously unknown. I had gone over this poster on Sunday with John and knew what it was saying, so I grilled the students to help them be prepared for today’s questions.
Another poster was from students at Villanova University and looked at the radiation fluxes in X-ray and UV wavelengths for several known exoplanets within 10 parsecs (32.6 light years) of Earth that are in the habitable zone (HZ). Using known data about their host stars, they determined that at least four of these planets, Gliese 876 b and d, GJ 581 d, and Tau Ceti f receive roughly the same radiation as Earth does. All of their host stars are also older than our sun, so in addition to liquid water they have a radiation environment that would allow life to exist as we know it.
Another NITARP group looked as YSOs in the Upper Centaurus Lupus nebula. This was done solely by Chelan Johnson’s students as an independent project beyond their initial NITARP run.
Another poster was by Ryan Lau, the Cornell graduate student whom I have interviewed previously on SOFIA (I’ll talk about this in a future post when I get a chance to finish my experiences with SOFIA last summer). He presented on the differences between three luminous blue variable (LBV) stars near the center of our galaxy. They are similar spectroscopically, but their surrounding nebulas are quite different because of differences in their environments. Ryan wasn’t with his poster, so I took a photo and moved on.
Of all the posters I saw, the most interesting one was by Steinn Sigurdsson, et al, from the Center for Exoplanets and Habitable Worlds at Penn State (website: http://www.astro.psu.edu/astro-research/centers-and-institutes/center-for-exoplanets) and Cal Poly Pomona. They are looking at galaxies that have an infrared signature, which could be the result of galactic civilizations giving off excess heat. The second law of thermodynamics states that all energy sources eventually work their way down to less ordered forms, resulting in random heat emitted in infrared wavelengths. Our own civilization emits at about 300 ° K, giving off about 0.01% excess from what would be emitted naturally. An advanced civilization would be able to detect our presence here simply by the heat we generate. The same goes for us detecting them. Even if they are more efficient at energy usage and emit at 200 ° K, they should still be detectable since there are few natural sources that emit at those wavelengths. If they are able to entirely use all the energy from a star, such as building Dyson spheres, they would still have to emit some waste energy or it would build up inside and make the sphere unlivable. Talking with Dr. Sigurdsson, who was at the poster, he put it in terms of the movie Star Trek 6: The Undiscovered Country: The thing has to have a tailpipe.
The most astonishing thing about my conversation with Dr. Sigurdsson wasn’t that someone has the audacity to look for such galaxies, but that 400,000 such galaxies have been discovered. The group is now winnowing them down, eliminating the many false positives that could be the result of recent star formation bursts or other natural sources. He said that they have already found several galaxies that are “intriguing.”
While talking about his poster, a graduate student commented, “If you think this is way out there, you should see the poster on the other side. He’s trying to prove that we can have sex with aliens!” So of course, I had to take a look. The presenter wasn’t at his poster, and it appeared to have been hastily put together from separate sheets of standard paper. It discussed the possibilities of actual alien contact and culture clashes given the huge distances involved. He had created his own version of the Drake Equation to determine the possibility of humans being able to reproduce with aliens (or serve as food for them). Both species would have to have similar left-handed proteins, amino acids, dextrose sugars, cell membranes, etc. to even serve as food, let alone similar enough DNA to reproduce. Sorry, but no human-Vulcan hybrids. And probably no Arcturian Megadonkeys either.
I couldn’t see where any actual science had been done, and the poster seemed to be more an advertisement for the author’s book than a serious scientific paper. But it was interesting. He brought up culture clashes between civilizations that were only hundreds of years apart technologically and were of the same species. If aliens did visit Earth, the results would be disastrous (this is Stephen Hawking’s conjecture). But he concluded that actual visits are extremely unlikely. Even if such civilizations exist, the great distances and energies involved to reach us would make the trip undesirable. He agreed more with what is called the Fermi Paradox: If such civilizations exist, then where are they? Why haven’t they visited us by now?
A poster next door was also interesting. Rachel Worth talked about the possibility of lithopanspermia, or the idea that life could have started on one planet (Mars or Earth) and spread to other bodies in the solar system. She had created a computer model of objects knocked off Earth or Mars during a large collision (such as happened during the Late Heavy Bombardment period) and ran it forward for millions of years. Much of the ejected rock fell back to the planet of origin (40%), much fell inward to the sun, but with increasing time the remaining rocks had orbits that became more eccentric and perturbed, with a few migrating outward where they could have landed on Europa or Titan, thereby carrying life with them and seeding these moons.
The Nearby Stars:
By this time my feet and legs were killing me after standing on a concrete floor for several hours. I returned to my room to rest and snack and check up on my wife. She has been able to finally get a ticket home to Utah today and is at the Miami airport. She will be flying home through Charlotte, NC.
I attended today’s Amateur Talk by Todd Henry of the RECONS team about how they are measuring the positions of the nearby stars, a topic that is obviously of interest to me since I’m writing an article on the 3D model I’ve developed to teach about this topic. I’ve used their data in my model. He described how the proper motions of these stars are being measured through astrometry, photometry, etc. The RECONS (Research Consortium on Nearby Stars) program is trying to find “missing” stars within 10 parsecs and to characterize all the stars within this area. They are now expanding to 25 parsecs. His team discovered the star system SCR 1845-6357 AB (which is in my model), found that Fomalhaut is a triple star system, and measured that the effective lower end of the Main Sequence for red dwarfs and the beginning of the brown dwarf sequence is at 2075°K, among many other discoveries. I wanted to talk with him after his address, but had to move directly to my next activity. I’ll try to read up more in the literature about their techniques. I do know they have been using a highly reliable 0.9 meter telescope at Cerro Tololo observatory in Chile. Their website is: http://www.recons.org/.
SOFIA Ambassadors and the NASA Origins Program:
I returned to the Exhibit Hall because I was asked to be part of a photo opp at the SOFIA booth. The new class of Airborne Astronomy Ambassadors was officially announced at noon today, so those of us who are here wore our jackets and gathered at the booth. We took photos as a group, with Cycle 0 through 2 representatives there. I took the time to interview Peggy Piper, Chelan Johnson, and Theresa Paulsen but had some camera and audio problems. My wireless lapel microphone had a broken connection to the battery, and I didn’t have the batteries on my HD camera charged up as much as I thought. Hopefully the onboard microphone was able to pick up decent audio.
I was able to interview Ryan Lau by his poster, but the second half I had to use my separate audio digital recorder (I’m glad I brought it) because the reserve battery on my HD camera gave out.
Here is a better copy of his poster he sent me after the conference: AAS 223 Ryan Lau
As a group we also talked with John Gagosian in the NASA booth. He is the director of the entire Origins Program for NASA, which includes SOFIA and several other missions. John explained to us about the new technology programs that look ahead as much as twenty years and provide seed money to develop strategic technologies that will be needed for the next decadal surveys. These include new types of glass for mirrors, new types of sensors, and all types of technology that could make space missions more powerful, more sensitive, and lighter in weight.
Dinner with my Cousin:
By 4:00 I was exhausted again and getting hungry. I also needed to rest my aching legs. I ate a few snacks I’d brought with me, then met my cousin Wade Williams at the hotel entrance. He drove me to his home in Springfield where I had a very pleasant dinner with him, his wife, Jenny, and son Jason.
Wade has a PhD in nuclear engineering and has worked at Lawrence Livermore Labs in California for over 20 years, on projects ranging from the laser fusion efforts to Department of Energy programs. He is now on loan for at least a year to the DOE national office where he is involved in management, budget, and oversight functions. They’ve been in Virginia about four months now, and it was nice to catch up.
It’s interesting to see where we’ve come over the years. When we were both teenagers, I used to stay at his house in Orem, Utah for a week while his sister, Mary, would stay with my sister in Deseret. Wade and I were budding engineers and scientists even back then; we would spend days planning and building elaborate spook alleys in his basement. Our displays were very dynamic and interactive, not just bowls of cold cooked spaghetti pretending to be brains. We had sliding doors that would trap people, a cage that would drop, a guillotine that would chop off a head, a dummy stabbing a vampire in a coffin, and our pride and joy: Count Yorga, Vampire.
There was a B horror flick by that name playing at a drive-in in north Orem that summer (1973) and it gave us the idea for one of the rooms on our spooky tour. We built a dummy and decorated it to look like a vampire, complete with a bag of “blood” inside its shirt (we ruined a lot of Uncle Clyde’s white shirts doing this). He could flap his arms/wings, drop to the floor after being stabbed with a stake in the heart, and even carry on a conversation through an intercom. All this was done with strings, rigged up and controlled by Wade from a closet while I acted as Tour Guide. We brought in kids from all over the neighborhood to see the final tour.
I’d like to think our creativity and problem-solving for these spook alleys has paid off. I’m still a tour guide of science, so to speak, and he’s a nuclear engineer, pulling on the strings that govern the laws of physics. We just don’t have to deal with vampires any more. Unless there are some wandering around at the DOE that I’m unaware of.
Wade returned me to the Gaylord hotel and I spent most of the remaining evening working on an application for an Innovative Teacher award through KUED, Salt Lake’s PBS station. I’d received an email requesting additional information, and it was due Friday, Jan. 10. I knew tomorrow would be too tiring to get it done then.