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David D. Levine
08 August 2010 @ 12:19 am
This morning's first plenary session was Carol Stoker of the NASA Ames Research Center, talking about the Drilling on the Moon and Mars in Human Exploration (DOMMEX) program from last season at the MDRS. The first half of her presentation was an overview of MDRS, which largely overlapped with my own presentation from yesterday, but I'm not going to fault her for that; she's on deadline and probably wasn't even here yesterday. It was interesting to see a different take on the same material, and (dropping modesty for a moment) to analyze the things that make my presentation more interesting and entertaining.

The DOMMEX part of the presentation was also interesting, because I'd read the emailed field reports and wanted to know more about it. Drilling will be an important part of any Mars mission (because so many interesting things are below the surface) and the DOMMEX experiments are intended to demonstrate different drilling technologies. The Mars Underground Mole (MUM), a self-driving impact-driven sampling robot, barely managed to embed itself completely in the soil, while a human-operated gas-powered backpack drill worked much faster and was more adaptable to unexpected situations. Bottom line: humans are more efficient and effective than robots. Other technologies tested included ground-penetrating radar and a manual core sampler (basically a small post hole digger, good for samples up to 1 meter in depth).

Dr. Stoker's presentation was followed by a panel discussion on Obama’s new space policy. None of them like it, particularly for the cancellation of the Ares heavy lift vehicle. The good news is that the Senate doesn't like it either and has restored funding for that program in their budget. We were all encouraged to write our representatives and ask them to support the Senate version of NASA's budget.

Carol Stoker returned after that with a presentation on the habitability of the Phoenix Lander site. She went into some detail on the factors that govern habitability (defined as suitability for Earth-like microorganisms, either in the present or in the past), what the Phoenix lander did to test for them, and how the site stacks up on each of them.

The items required for habitability are: liquid water, energy in forms usable by living things, the presence of the chemical building blocks of life, and the absence of factors inimical to life such as radiation and toxins. Phoenix had an extensive suite of instruments to detect most of these things. Its landing site (selected for the highest concentration of ice outside of the north ice cap itself) had plenty of direct and indirect evidence of water; chemical energy in the soil in the form of perchlorates and iron; solar energy available for photosynthesis, plus mica rocks in the soil which are transparent to visible light but opaque to damaging UV; and most of the chemical building blocks of life (except for nitrates, which might be present but were not tested for). Unfortunately, temperatures at this near-polar location are too low for life most of the year. However, in the distant past Mars had a much larger axial tilt and during the northern summer this part of Mars could get warmer than Antarctica does on Earth today. The Phoenix lander site is more habitable than any other site visited and deserves a follow-up expedition to search for signs of ancient life below the surface (which ties into her previous presentation on drilling).

After that plenary session I stuck my head in on Mars Camp, a family-friendly event that was open to the public. It was just hopping with kids and parents, flying flight simulators, working in a glove box, directing robot arms, and enjoying an inflatable planetarium. A very keen addition to the conference. I also picked up a couple of cool Mars coloring books.

I skipped the afternoon program in favor of a visit to the Museum of the United States Air Force at Wright-Patterson Air Force Base, a mere 15 minutes' drive away. I'd been told that it has a better collection of airplanes than the Smithsonian, and I have to agree with that assessment. click for photosCollapse )

In the evening we had the annual banquet, with pretty good food and an awesome presentation by Dr. Carolyn Porco, director of the Cassini mission's CICLOPS Saturn Imaging Team. Her collection of amazing images of Saturn, its rings, and its moons (over 60 moons are now known) was like a year of Astronomy Pictures of the Day all at once, and she was excellent at explaining what we were seeing and why it was exciting. I had not known that we learned some amazing things about Saturn's rings at its equinox, when the sun shines directly across the rings and we can see the long shadows of any variations in height within them. The wobbles in the ring on either side of the moon Daphnis, for example, were revealed to be mile-hile walls of rubble thrown up by the moon's passage (the ring itself is just 30 feet thick). I had also not seen the amazing photos from the surface of Titan returned by the Huygens probe, or the plumes of salty water erupting from the surface of the moon Enceladus.

I had convivial table companions for the banquet, handed out many business cards, and made some professional contacts whose potential is very exciting. About which more later, if any of them should happen to pan out. For now, to bed.

 
 
David D. Levine
08 August 2010 @ 07:21 pm
I'm on an hour-and-a-half layover at the Salt Lake City airport, where there are little carrels with power outlets and free wi-fi. Why can't all airports be like this? (Though, all in all, I'd rather have returned the way I came, via Seattle, which would have given me at least an hour less time in the air.)

The day started with the usual end-of-convention prepositions: get up, wash up, dress up, pack up, check out, eat up, and check in (for my flight). I bought my ticket from Alaska Air, but the flight is actually a Delta flight, and since Alaska doesn't actually fly to Cincinnati itself I was unable to check in on the Alaska web site (which for some peculiar reason requires you to specify the originating city as well as the confirmation code). Fortunately, they gave me a Delta confirmation code as well and I was able to use it to check in via the Delta web site. But the boarding pass, when printed on the hotel's printer, had its outer half-inch cut off and would probably not be acceptable at the airport. Grr. (As it happens I had to check a bag anyway, so it cost me little time to reprint my boarding pass at the gate. My bag, by the way, weighed the same 50 pounds as my Monster Bag from MDRS on the way out, but I seem to have sold at least 12 pounds of books at the conference.)

Having dealt with all that, I was only a bit late for the morning's plenary session by David Chuss, NASA Goddard Space Flight Center, about The Early Universe. Much of this talk was not new to me, but it's nice to be reminded about what we know and how we know it.

He started with the earliest development of cosmology, going back to Tyco Brahe and Newton and the statement "Mathematics starts with a truth and looks at the consequences; cosmology starts with the consequences and looks for the truth." Einstein's general relativity implied that the universe was either expanding or contracting, not static, and he added a term (the "cosmological constant") to get rid of that. Not too much later, Hubble's observations of the apparent motion away from us of distant objects showed that the universe was indeed expanding, and Einstein took the constant back out, saying it was his "greatest blunder."

So, astronomers reasoned, if the universe is expanding it must be cooling. This prompted them to look for the red-shifted light of the early, hot universe, but they were scooped by a couple of microwave engineers who were trying to track down the source of some interference in their antennas and wound up with a Nobel Prize.

NASA has launched several satellites to map this cosmic background radiation, with increasing detail and sensitivity, and they are telling us a lot about the early universe. This radiation is slightly uneven (anisotropy), which tells us that the early universe was lumpy; these lumps coalesced into galaxies, stars, and us. Doing a Fourier transform on this radiation reveals the power curve of the early universe, which (through math I have never been able to follow) explains where the fundamental particles like baryons came from and whether the universe is positively curved (closed, leading to an eventual collapse) or negatively curved (open, continually expanding). Weirdly, the data tells us the universe is exactly flat, which is unexpected and unstable (the slightest curvature in either direction will tend to increase). No one quite understands yet how this can be.

Recent observations of extremely distant objects reveal that they appear to be accelerating away from us -- that is, the expansion of the universe is accelerating. This implies that the universe is mostly (over 75%) composed of "dark energy," whose properties are completely unknown -- all we can say is that it accelerates expansion. A negative value for Einstein's cosmological constant fits this data, but we still have no idea what this might mean in real-world terms.

Careful examination of lumpiness in the cosmic background radiation hints that the very early universe expanded faster than the speed of light ("inflation"); we don't know how this is possible, though perhaps in the first moments of the Big Bang the laws of physics had not yet coalesced into their current form. NASA is launching the Dark Energy Explorer and Webb Telescope satellites to investigate these questions.

In 1900 they thought 20th century physics would be boring, with only a few questions left to answer (the "ultraviolet catastrophe" and the presence or absence of ether). The search for answers to these questions led us to relativity, quantum dynamics, transistors, and GPS. We don't have such low expectations today, but we know we will be surprised.

Kevin Sloan was up next, talking about the Mars Society's University Rover Challenge, which is held each year at the MDRS in Utah (students participating in the challenge stay at a hotel in Hanksville, not at the hab).

The University Rover Challenge gives engineering students a concrete project that they can use to build skills, work in teams, and maybe win cash prizes. This year's URC had 12 teams from 4 countries; 7 teams made it to Utah for the final trials.

We believe that astronauts will work together with various kinds of machine to amplify their abilities. Rovers can, for example, be used to perform tasks outside a Mars base without having to suit up. The rovers in the challenge are wheeled (or tracked) vehicles with cameras and a manipulator arm; they are remotely operated, not autonomous. This is an engineering design, construction, and operation challenge with no artificial intelligence component. Rovers are limited to 50 kilograms and must perform 4 different tasks (they can be reconfigured with different parts for each task, but no configuration can be over 50kg). Most rovers weigh in at right around 49.9kg, but one team was surprised at the official weigh-in and had to quickly strip the rover of unessential cameras and batteries to get under the line.

The four tasks are: Equipment servicing task: navigate to a panel, read the instructions posted there using the rover's camera, and perform several tasks such as flipping switches and plugging in an electrical cord (this part was really hard, only the Oregon State University team was able to do it). Site survey task: find and survey several markers in a field, recording their coordinates with GPS-like accuracy. Sample return task: search for and return samples of biological interest, perform field analysis, and deliver field briefing to judges. This task requires engineers to work with biologists who are directing the work, rather than just drive and scoop. Emergency navigation task: cross difficult terrain, find a stranded astronaut, and deliver emergency supplies in less than 20 minutes. This one too was won by the Oregon State team. One of the Polish teams would have won the contest if they had gotten the full 100 points for this task, but their rover with its single camera was looking the wrong way and drove right past the astronaut.

We got a talk from the winning Oregon State team about their rover design and the lessons they learned from the previous challenge, which was very cool, but I'm running out of time here.

The final session I saw before departing the conference was Joseph Palaia from the NewSpace Center, talking about a planned "themed attraction" called Interspace. He said that the current wave of commercial space development is a "new barnstorming era" and very exciting, but direct participation is extremely expensive and the facilities are too isolated and not set up for the public. Current science and aerospace museums are focused on the past, not this new technology. Interspace is intended to be an interactive, immersive experience for tourists based on what's happening now and in the near future in space. They have a 75-acre site in Florida, near the Kennedy Space Center, and are currently trying to nail down the $72 million they'll need to build it. It looks like a lot of fun and I hope they succeed.

Then I drove to Cincinnati, dropped off the car, and flew to Salt Lake City without incident. At the moment it looks like my flight to Portland is about 15 minutes behind schedule, but I don't anticipate any problems getting home. See you soon!