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Posts Tagged ‘Apollo’

LEAG Conference, part 2

Thursday, November 26th, 2009

 

While the LEAG meeting in Houston last week featured lots of exciting new results from LCROSS and LRO, it also provided an opportunity for discussion about the future of lunar exploration, human spaceflight, and NASA. The main theme of the meeting was sustainability: If and when humans return to the moon, how do they do so in a sustainable way?

One point that everyone (as far as I could tell) agreed on is that the Apollo model is not sustainable. By “the Apollo model” I mean what the lunar scientists like to call “sorties.” You build an enormous rocket, you take everything you need with you, you leave all of your junk there and you never use it again.

An alternative approach would be incremental or cumulative. You would probably start with several robotic precursor missions that would establish where your key resources are, and perform technology demos. Can we extract oxygen from lunar rocks? Can we extract water from lunar soils? Can we control lunar dust so that it doesn’t get into everything and cause all of our machines to break down? Can we safeguard astronauts from radiation?

If we find satisfactory answers to these questions, then we can build a base on the moon, although another possibility would be a base at the L1 point (or Lagrange point) where Earth’s gravity and the moon’s gravity cancel each other out. The things that you need to bring from Earth are brought a little bit at a time, somewhat like the way that we built the International Space Station. You don’t just go there, use your stuff once, and leave it. You need to re-use as much as you can. And finally, if there is anything that you can produce onsite, you do it. That primarily means (at this stage of the discussion) water, atmosphere, food, and propellant.

What I’ve just said may seem obvious, but it was surprisingly non-obvious for a very long time. Those of us who lived through the Apollo era were very surprised when the trips to the moon stopped. A lot has been written about the possible reasons: the public’s apathy, the Cold War politics that went into the moon race, the Vietnam War that sapped the American budget, etc. But maybe it had to happen. The whole approach was unsustainable.

Even now, many people still want to reproduce the Apollo model as we prepare for missions to Mars. This was the chief criticism that I heard of the Augustine Commission report. The “Flexible Path” option, many people felt, was just “Apollo on steroids,” traveling to more places with one-shot missions instead of building up the infrastructure for a sustainable presence in space.

I suppose I should name some names here. Paul Spudis is an especially passionate advocate of the idea that we must think about sustainability when we return to space. I wish I could just copy his whole presentation here, but that would not be very original. He said, “The goal is not to excite the public. The public must see the value in lunar exploration, which is different from making it exciting.” He took issue with the Augustine Commission’s conclusion that the ultimate destination (their words) is Mars. “The goal of returning to the moon is to become a spacefaring species,” he said. I think this is a great mission statement. Mars is not the ultimate goal; the ultimate is to be able to go wherever we want. Spudis would build up that capability on the moon.

Also, Igor Mitrofanov gave a perspective from the Russian space agency: “We will support missions to the moon if we will go there forever. Then we will participate as a nation.” He compared the moon to a new continent: “The first explorers looked for a place for a settlement, a bay, a harbor,” he said. Obviously he is arguing for a base approach rather than a sortie approach.

Many participants in the meeting said that sustainability would have to mean economic viability. Paul Spudis, as usual, formulated the question nicely, by listing three stages of lunar exploration: Arrive, Survive, Thrive. So far we have shown that we can Arrive. The next step is Survival — showing that we can stay for a long time on the moon — but ultimately the point of the whole exercise is to Thrive.

Both Spudis and Bob Wegeng, of the Pacific Northwest National Laboratory, drew analogies with the development of railroads in the 19th century. I went to lunch with Wegeng, who exposited at length about the railroads and told me some things that I did not know before. In school (in the U.S., at least), we all hear about the golden spike that completed the first transcontinental railroad in 1869. It’s part of our national mythology, just as much as the moon landing 100 years later. But that railroad went bankrupt several times, in spite of all of its government support!

The first economically successful transcontinental railroad, according to Wegeng, was the Great Northern Railway, built by James Jerome Hill. Wikipedia says it  was ”the first transcontinental built without public money and … one of the few transcontinental railroads not to go bankrupt.” Hill built up the Great Northern’s customer base by selling homesteads to farmers along the railroad route and even building industrial plants that would be served by his railroad.

If we want to learn from this example, it suggests that we will Thrive on the moon when a mega-corporation comes along, led by one person with vision, which does not just focus on the transportation technology but constructs a whole econosphere on the moon.

Who could that mega-corporation be? Not the current aerospace companies; they are too much like the government-backed railroads that failed. What about Google? I don’t know. It seems a little bit outside of their skill set, but they do have the vision. All things considered, the vision is probably more important than the skills or the capital, which can always be acquired on the way.

Anyway, getting back to the LEAG meeting, the one presentation that really looked at the moon from an economic point of view was by Brad Blair, a mining engineer who also works with the Canadian Space Agency. His paper was actually out of date — he presented an economic analysis of investing in the moon that he published back in 2002 or 2003. He analyzed five different scenarios, and in the last, ridiculously optimistic scenario he showed a possible return on investment in the range of $3 to $4 billion. I think the importance of his study lies not so much in the specific numbers or conclusions but in the methodology. I think his work needs to be updated for the decade of the 2010s. The discussion of lunar exploration has been completely dominated so far by scientists and engineers, but at some point some economists need to get involved.

Finally, in the discussion of sustainability, there were some interesting points made about public opinion. Spudis calls it the “50-50-50 problem”: public support for NASA has hovered around 50 percent for and 50 percent against for 50 years. And that includes the supposed heyday of NASA when we were racing to beat the Russians to the moon. Even back then, there were a lot of people who didn’t see the point, and argued that the money would be better spent solving problems on Earth. Public support for NASA has never been significantly more than 60 percent or less than 40 percent.

Spudis’ point was that if our justification for exploring space is “inspiring the public,” then we will never succeed. We need to go beyond inspiration to providing economic value.

At the same time, someone (I’m not sure who) pointed out from the audience that 50 percent support is not really a bad thing. Politicians are glad to have 50 percent, because it means they can be re-elected. Popular support for a lot of our public institutions runs a good deal lower than 50 percent. So instead of asking what NASA is doing wrong, perhaps we should advertise the fact that they are doing something right. Message to politicians: If you invest money in NASA, about half of the population will support you, as they have now for half a century.

The big unknown, at this moment, is whether any politicians are listening … especially the ones that matter, who live at 1600 Pennsylvania Avenue.

Tags: Apollo, Augustine Commission, base, Economy, James Jerome Hill, LEAG, Paul Spudis, Politics, railroads, resources, sustainability
Posted in Arrive, Future exploration, Meetings, NASA, Survive, Thrive | 6 Comments »

“That’s Daddy’s rocket!”

Tuesday, August 25th, 2009

 

In an earlier post I wrote about the LCROSS mission, which is due to make its crash landing on the moon on October 9. (Mark your calendars!) In July I talked with Tony Colaprete, the Principal Investigator for the mission. I apologize if there is a bit of unevenness in this interview, because I have cobbled it together from three sources — our conversation at the Moon Fest, an e-mail, and his presentation at the Lunar Science Forum. Answers have been edited for length but I have tried to preserve Tony’s wording.

Tony Colaprete (NASA photo)

Tony Colaprete (NASA photo)

DM: You told me that you were born the week before the Apollo 11 landing. So, happy birthday! How big an inspiration have the Apollo missions been to you?

TC: I was born July 16, 1969, the day Apollo 11 launched. My father was heavily involved in the Apollo program, and one of my early childhood gifts was the classic Snoopy dressed in an EVA suit. So, yes, the Apollo mission was a huge influence, not only because they were so amazing but also because of my father’s involvement. … I am amazed to think that the folks who did Apollo were on average around 25 to 27 years old! The commitment, devotion, and guts those people had is inspiring.  I just hope I can do things half as right as they did for the Apollo program.

DM: When and how did you decide that you wanted a career in space exploration? How did you prepare for it?

TC: When I graduated from high school I knew I wanted to either go into the sciences or art. Luckily for us all, I decided to go into the sciences. … Very early on, though, I loved being in the woods near Boulder, Colorado, where I grew up. I would go for hours by myself and just watch what went on around me. So very early on I knew I loved systems, how things work together and influence each other … I still do.

I worked on instrumentation at the University of Colorado through the Space Grant College and the Laboratory for Atmospheric and Space Physics for a few years after getting my bachelors degree in physics. I was taking a few graduate classes (including my first planetary atmospheres class, taught by a very inspiring David Grinspoon), when I realized I wanted to pursue a graduate degree in planetary sciences. Luckily, CU is a great place to do that!

While I was doing my graduate work I continued to work on instrumentation for sounding rockets, space shuttle flights, and small spacecraft. This combination of science and engineering (again, systems!) was key, I think, to helping me get where I am now.

DM: How did the idea for the LCROSS mission come about?

TC: When LRO moved up to a bigger rocket, they had room for an extra 1000 kilograms on board, and a call for proposals went out for a co-manifested mission. And by the way, they said, you have only 2½ years to get it done, and you can’t spend more than $80 million.

When the call was announced, we [at NASA Ames] formed a “Tiger Team” to come up with ideas. Early on in the process we considered an impact mission, but I concluded that with only 1000 kilograms to work with, the impactor mass would be too small.

Another person in the group, Geoff Briggs, suggested using the spent upper stage of the launch vehicle. He has since said that he got the idea from someplace else. I ran some numbers and convinced myself that an impact by an object of about 2000 kilograms would produce a cloud observable from earth.

At about the same time, Northrop Grumman submitted a [proposal] that was also using the upper stage and also had a small shepherding satellite that could make observations. An engineer on the Tiger Team saw the idea and told me about it. We had a couple Northrop Grumman scientists come up and we discussed our ideas and the rest was history. So I don’t think it was any one person’s idea, but just enough people with the same idea!

In the end, LCROSS was selected out of 17 proposals. We cheated the 1000 kilogram limit — it’s 3200 kilograms, because we held on to the spent Centaur [rocket stage], which is about 2300 kilograms.

DM: Have you ever watched a launch in person before? If so, how was it different, knowing that it’s your own experiment that is going up?

TC: I’ve flown payloads on sounding rockets and shuttle flights, and have seen those go before. This Atlas moved so slow at first! I thought to myself, “You’d better pick up some speed or you’re not going to make it!” The sounding rockets and the shuttle use solid fuel, whereas the Atlas V is all liquid — it’s a big difference!

My biggest concern at launch was whether we could get off on the 17th or the 18th [of June], because those two days result in very good impact observing conditions for the continental U.S. The 19th was not so good, and on the 20th [there were no good times] at all. So I was very glad the weather broke in time for us  to go on  June 18.

DM: Have there been any exciting moments since the launch?

TC: I held my breath when we turned on the instruments for the first time. That was a moment of sheer terror and anxiety for me. Also, I’ll hold my breath again on August 1, when we turn them back on. Radiation and vacuum can have effects on detectors, so they always degrade over time. Once we know that they are working, I will be very confident that the payload will survive until the impact with the moon. [According to the mission page, the checkout of the infrared cameras and spectrometers on August 1 went very well. They took spectra of Earth and -- stop presses! -- detected oxygen, water, and vegetation! -- DM]

DM: What are you expecting to see when LCROSS hits the moon?

TC: There are a couple different models of how the water gets to the south pole and two different predictions for how it is distributed. We describe them as the smooth versus chunky models. In the smooth model, the ice is uniformly distributed on the scale of this room, with about a 1 percent concentration of ice. If that model is correct, LCROSS will have very good chances of detecting it. LCROSS should be sensitive down to concentrations of half a percent.

However, if the ice is chunky, with smaller pockets of up to 10 percent ice, then we might have a 10 percent chance of hitting something. If we hit one of the “peanuts” in the chunky peanut butter, we’ll know. This would immediately distinguish between the two competing models.

My biggest fear is that we won’t see anything — that it will be a dud. But even in that case, then we’ve learned that the distribution isn’t smooth. That is important to know, because it means that your next mission [i.e., a lander to search for ice on the ground -- DM] had better be mobile.

DM: How does the LCROSS mission compare with other spacecraft that have crash-landed on the moon (Lunar Prospector, the European SMART-1, and the Japanese Kaguya)?

TC: None of those other missions were designed as impactors. The biggest difference is that they typically hit the moon at a low, grazing angle, because they were in orbit around the moon. LCROSS is not, it’s in orbit around the Earth. [This is a rather non-obvious fact that is illustrated on the flight director's blog at this link. LCROSS doesn't "go to the moon." It goes into an orbit around Earth that is the size of the moon's orbit, and then the moon just runs into it! - DM] So it will hit at a very steep angle, around 85 degrees. Also, we’re bringing quite a bit of mass. So those missions can’t be compared to LCROSS for visibility, size, and impact angle.

DM: How big a crater will the LCROSS impact make?

TC: We’ve done simulations using Apollo-era technology, and we expect the crater to be about 20 meters wide — the size of a tennis court. We expect the plume to contain about 300 to 400 metric tons of material.

DM: On the LCROSS website you have a list of several possible target craters. Do you have a favorite on this list?

TC: Faustini would be my preference. It’s a very old, large crater, so the material in there has been in shadow for a very long time — around two and a half billion years. We want to hit somewhere that is flat and fluffy, not blocky and steep. One thing against it is that it’s right on the limb of the moon. So the ejecta have to go up 2 kilometers in order to be illuminated by the sun. In some of the other target craters, the ejecta only have to go up about 500 meters. But for earth observers, a position on the limb means that you get high contrast [against the darkness of space -- DM], and that’s good.

DM: I think it’s interesting how you have been able to use the results of other recent missions to narrow down the list of targets for this mission. Can you talk a little bit about  the synergy between missions, and especially the Japanese Kaguya spacecraft?

TC: The topography from their laser altimeter has been invaluable. First, it lets us calculate the slope of the ground. You don’t want to hit a slope [because you would then lose the benefit of a high impact angle -- DM]. Kaguya also gave us amazing information on the depth of the craters. Some of the errors in the previous estimates were significant, on the order of 500 meters to a kilometer. From the Kaguya terrain camera we got information on the surface roughness and albedo [reflectivity] of the craters. So, overall, they matured our current data set.

Also, with new LRO data coming online, we’ll be refining our numbers continuously to make the wisest choice of target. We will finally make an impact site selection by 30 days before impact, roughly the first week of September.

DM: How can ordinary people contribute to the LCROSS mission?

TC: Amateurs have already contributed, and with an impact with the moon high and the skies dark as far east as Texas, I hope many more will continue to contribute.

One thing to realize is that professional astronomers typically don’t point their telescopes at the moon. To most of them, the moon is a source of light pollution. So when we asked the best in the world to look at the moon for a change, there was a steep learning curve. One thing they needed to learn was how to find the crater you want to point to amongst a hundred or so other craters that look very similar. The shadows and bright areas change dramatically with small changes in the sun angle, so finding one’s way around the moon can be difficult if one has never looked before. To help, we asked the amateur community to image the moon at all phases and tilts so that we had a library of sorts for the various light conditions.

During the impact, amateurs with a minimum of about a 10-12 inch telescope can observe the impact. We will be soliciting these observations and will share them with others. [There is a Google Group for amateur observers at this link -- DM.]

DM: Finally, do your kids know that “Dad is a rocket scientist”? If so, are they proud of it, and are they paying any attention to the LCROSS mission?

TC: I have a son who is two and a half and a daughter who is five years old. They came to the launch, and when they look at the moon now they say, “Daddy’s rocket is flying to the moon!” After the launch my wife and children took a different flight home than I did. During the layover, on one of the cable news channels playing at the gate, they showed a replay of the launch. My children both yelled, “Daddy’s rocket!” My wife says that the people around them looked with a bit of a skeptical stare until she said, “Actually, it is their daddy’s rocket.”

Tags: Ames Research Center, Apollo, chunky, craters, interviews, Kaguya, LCROSS, LRO, Northrop Grumman, smooth, telescopes, Tony Colaprete
Posted in Missions, Science | 3 Comments »

And in other news, the sky is blue …

Friday, July 17th, 2009

 

What is It?

What is It?

Can you tell what you are looking at in this picture? Hint: In the dead center of the picture, look for something that doesn’t cast a shadow like anything else. Instead of a depression, look for a tiny bright spot that casts a long shadow horizontally across the moon’s surface.

Did you find it? You’re looking at the Apollo 11 Lunar Module! (Actually, it’s just the descent stage, which remained on the moon when Neil Armstrong and Buzz Aldrin took off in the ascent stage.)

The Lunar Reconnaissance Orbiter (LRO) took the picture earlier this month, along with photographs of all the other Apollo landing sites except for Apollo 12. NASA released all the photographs today.

This is a piece of news that SHOULD be about as surprising as, “Scientists today released photographic proof that the sky is blue.” Nevertheless, it is actually huge, because there has been a small but vocal contingent of people claiming in recent years that all of the Apollo moon landings were faked. They even managed to convince the Fox television network to run a special about the “moon hoax” a few years ago. It’s now going to get a lot harder for them to make their case.

The place you should go to read about all of this is Phil Plait’s wonderful blog, Bad Astronomy. Plait has run a website and a blog for years that debunks silly claims like UFOs, faces on Mars, etc. … and one of the battles that he has fought all this time is the one against the moon-hoaxers. So for him, the release of these NASA images must be a huge personal triumph.

What’s so great about it is that here is one case where the conspiracy theorists have gotten themselves trapped — they have occupied a position that can slowly, bit by bit, get chopped out from underneath them, as the LRO missions and other missions get higher- and higher-resolution pictures. This is something that we can only dream of in some of the other contentious non-debates that science has to deal with. Imagine, for example, that we could actually go back into the past and get photographic proof of evolution happening … but we’ll never be able to do that. And so the evolutionism versus creationism non-debate will go on forever. However, for the moon-hoax non-debate, I think the end may be in sight.

Now let’s put that aside, like a bad dream, and also appreciate these pictures for what they show. I love the Apollo 11 picture precisely because the Apollo 11 lander is so different from anything else in the picture. It really says, “We are the aliens here.”

Next, here is part of the photograph of the Apollo 14 landing site.

Apollo 14 Landing Site

Apollo 14 Landing Site

Here the lighting was so good that you can actually see the astronauts’ footprints leading from the lander (right) to the Apollo Lunar Surface Experiments Package (left of center). Amazing! Of course, as my wife said, “Are those footprints or footprint-shaped craters?”  ;-)

Also the photograph of the Apollo 16 landing site documents another little bit of Apollo history:

Apollo 16 landing site

Apollo 16 landing site

In this one you can see the shadow of the lander extending all the way across a nearby crater. Apollo 16 came perilously close to landing in this crater, and the photo shows what a close call it was. Quoting from David M. Harland’s book, Exploring the Moon: The Apollo Expeditions: “They were in the centre of a subdued crater about 100 metres wide. What they did not discover until they ventured outside, was that the rear footpad was a mere 3 metres beyond the rim of the 15 metre crater that Young had lost sight of [while landing the LM]. When he had hovered to select a spot on which to land, he was directly over the crater, and had narrowly missed landing on the rim.”

Fascinating stuff, and a wonderful 40th-anniversary treat from NASA!

Tags: Apollo, Apollo 11, David Harland, footprints, landers, LRO, lunar surface, Phil Plait
Posted in Media, Missions | 3 Comments »

New Scientist cover!

Monday, July 13th, 2009

 

Forty years later

Forty years later

In honor of the 40th anniversary of the Apollo 11, New Scientist has a special eight-page feature this week on the legacy of Apollo, called “Why the moon still matters.” I wrote the cover story, to which they gave the provocative but also quite appropriate title, “It’s the solar system, stupid.”

Although I didn’t make up the title, I think it rather nicely sums up the main message of my article, which is that by studying the moon rocks we learned about a lot more than just the moon — we learned about how the whole solar system was put together.

Besides my article, there are four other articles in the package, all very much worth reading. Stuart Clark writes about an experiment that the astronauts left on the moon that is still returning data, 40 years later: the laser reflectors that are used to measure the distance from Earth to the moon. Greg Klerkx asks what the nationality of the next person to set foot on the moon will be. Hint: There’s a very good chance that he (or she) won’t be American. Linda Geddes discusses plans to preserve the historic sites of the early moon landings. Ironically, they won’t need any preservation at all until humans start going back to the moon — but then we will have to think about how to keep every space tourist from placing their boot print next to Neil Armstrong’s. Finally, Henry Spencer speculates about what life on the moon (pop. 5000) would be like today if we hadn’t stopped sending astronauts to the moon in 1972. By the way, I think his scenario is a little bit too optimistic, but that’s what makes speculation fun.

Elsewhere in the issue, there is a short interview with Brian Eno, who wrote a musical composition called “Apollo” in 1983, which will have its first live performance at the Science Museum in London on July 20. I learned something from this interview I never knew before: “Every [Apollo] astronaut was allowed to take one cassette of their favorite music. All but one took country and western,” Eno said. I wonder who the one was?

The New Scientist website also has a comments forum. One guy wrote in and said that he doesn’t understand why we aren’t sending robot missions up to the moon every month by now. “I WANT MY MOON ROVERS!!” he wrote. That’s the spirit! Unfortunately, the New Scientist site includes some comments by the tiresome and rather sad people who believe that the moon landings were faked. If you want to discuss the articles without having to read such pointless debates, please feel free to comment here. I promise to delete all comments from moon-hoax-conspiracy theorists.

P.S. for word fans: In my article I used the word “gambolled” in print for the first time! According to the fascinating website www.wordcount.org, “gambolling” is the 81,852-nd most common word in the English language. Amazingly, it follows “atns” (huh?) but it is more common than “sundae.” The word “gambolled” is not listed.

Tags: anniversary, Apollo, music, solar system, speculation
Posted in Media, Science | No Comments »

Liftoff!

Friday, July 3rd, 2009

We're on our way!
We’re on our way!

To all space enthusiasts, especially those who are interested in the moon, welcome! I’m celebrating the launch of my blog, appropriately enough, with a picture of a rocket launch. On June 18, 2009, NASA successfully sent its first two lunar missions of this millennium into orbit: the Lunar Reconnaissance Orbiter (LRO) and Lunar Crater Observation and Sensing Satellite (LCROSS). (Image credit: United Launch Alliance/ Pat Corkery.)

LRO Logo in center, LCROSS just above it

LRO Logo in center, LCROSS just above it

It’s an exciting time to start a moon blog. Not only have the LRO and LCROSS missions gotten underway, but also the Indian Chandrayaan-1 mission is still going and the Japanese Kaguya mission has just ended. We also have a big anniversary coming up: the fortieth anniversary of the Apollo 11 manned mission to the moon. Two days after that, the longest total solar eclipse of the 21st century will take place — and as you know, we wouldn’t have eclipses without the moon.

That is a sample of the topics I plan to cover in my blog. I also hope to include interviews with people who are working on moon-related projects, whether they be NASA or private, science or literature or art. Yes, I do intend this blog to be not just about lunar science. The moon plays a large role in our culture, so I don’t think that we should just stick it in a box labeled “Science” and forget about all the other things that the moon means to us. But that’s a topic, or discussion, or rant for another time!

This blog takes its name from the working title of a book that I wrote six years ago, which was published by John Wiley & Sons: The Big Splat, or How Our Moon Came to Be. It’s a figure of speech my grandfather used to employ often. If you “think so-and-so hung the moon,” that is another way of saying that you are a great admirer of said person.

Eventually, my editor and I decided that “Who Hung the Moon?” was not an appropriate title for the book. The main reason, for him, was that book titles should not be in the form of a question. This was news to me — hadn’t he ever heard of “Who’s Afraid of Virginia Woolf?”? My reasons were different. I was concerned that “hung the moon” might be an idiom from a specific region — the American South — and not everyone would understand it. And finally, “Who Hung the Moon?” didn’t quite say what the book was about. The title we chose, The Big Splat, or How Our Moon Came to Be, was a much more straightforward description of the book’s contents.

Nevertheless, I still like the abandoned title. But it was actually my SO (Spousal Overunit), Kay, who suggested reviving it as the title for this blog. She did more than suggest it — she designed the whole look of this webpage around it, so that by the time she was done I couldn’t possibly say no! If you like the design, please send your compliments to her (and check out her quilting blog, www.allaboutapplique.net).

See the “About” pages if you want to read more about my background and reasons for writing this blog. But now, let’s get started!

Tags: Apollo, Chandrayaan, eclipse, Kaguya, LCROSS, LRO, NASA, spousal overunit, The Big Splat
Posted in Missions | 4 Comments »

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