Erlanger Crater: ice on the moon?

Where there’s ice, there’s hope of human survival – or so goes the thinking around exploration of our planet’s solo moon. The question of moon living was revitalized last week when two satellites recently passed by the Erlanger Crater, at the moon’s north pole, to radar-probe for evidence of ice. I wonder what we would do if it was found.

“If hopes of colonizing the Moon are ever to become reality, water needs to be found there. Sizeable amounts of ice could provide Moon-dwellers with drinking water and, if they split it into its atomic components, hydrogen for fuel and oxygen to breathe.”

That’s a quote from Nature magazine in October 2006, not a science fiction novel; you can see how the link between frontierism and ice easily seduces the imagination.

“If hopes of colonizing the Moon are ever to become reality, water needs to be found there. Sizeable amounts of ice could provide Moon-dwellers with drinking water and, if they split it into its atomic components, hydrogen for fuel and oxygen to breathe.”

That’s a quote from Nature magazine in October 2006, not a science fiction novel;  you can see how the link between frontierism and ice easily seduces the imagination.

But first, how could frozen water exist on the atmosphere-free moon? The theory is that ice may have built up in permanently shadowed lunar craters from comet impacts over the millenia. In fact, the theory is strong enough that NASA and the Indian Space Research Organization (ISRO) put months of work, and millions of dollars, behind a meeting of satellites that lasted for – well, about four minutes, on August 20th (or 21st, Indian Standard Time).

nasa380723main_erlanger_crater_med
http://www.nasa.gov/mission_pages/Mini-RF/news/tandem_search.html

NASA’s Lunar Reconnaissance Orbiter (LRO) and India’s Chandrayaan-1 took a close look at the Erlanger Crater (87 N, 28.6 E, 10 km diameter, for the techies). Coordination was a challenge to navigate “because both spacecraft are traveling at about 1.6 km per second and looked at an area on the ground about 18 km across,” explains Universe Today.

The two satellites came close so they could perform a bi-static reading of the Erlanger Crater: Chandrayaan-1 sent the signal, and the LRO received it.

UT continues: “‘The advantage of a Bi-Static experiment is that you’re looking at echoes that are being reflected off the Moon at an angle other than zero,’ said Paul Spudis, principal investigator for Chandrayaan-1… ‘Mono-static radar sends a pulse, and you are looking in the same phase or incident angle. But with Bi-Static, you can look at it from a different angle. The significance of that is ice has a very unique bi-static response.'” Got that? I think I do ….

Low resolution Earth-based radar image of the North Pole of the Moon, pointing out the crater Erlanger (Arecibo Radiotelescope Puerto Rico, photo NASA website)
Low resolution Earth-based radar image of the North Pole of the Moon, pointing out the crater Erlanger (Arecibo Radiotelescope Puerto Rico, photo NASA website)

The ice-seeking data was downloaded at John Hopkins University in the USA and at the Indian Deep Space Networks antennas at Byalalu, near Bangalore, when the satellites passed over those geographies on Aug 21. It will take some time for NASA and ISRO scientists to analyze, but the numbers give a brand new measurement of a permanently dark lunar crater from a distance of only 200 km above the surface (read the ISRO news release here).

Which brings us back to the initial question. If there is ice on the moon, what would, should, or could we do about it?

It’s a challenge to track what is known about the moon, because scientists (and, equally, reporters) inflate conjecture into present-tense reality statements with a speed that has to be part enthusiasm and part politics. And the rest of us can’t wander on by for a lunar weekend to check it out for ourselves.

In 1998, The Tech (“MIT’s oldest and largest newspaper & the first newspaper published on the web”) quotes an excited, definitive series of comments from NASA scientist Alan Binder, Lunar Prospector principal investigator from the Lunar and Planetary Research Institute.

Binder’s statements are definitive, positive, authoritative: “We have found water at both lunar poles!” and “For the first time, we can go to another planetary body and fuel up.”

At the time, the US Lunar Prospector spacecraft was orbiting 60 miles above the moon. Water wasn’t directly observed, but hydrogen was. The article explains that “hydrogen by itself is not stable at lunar temperatures and will only remain if it forms bonds – becomes water-ice for example – so the hydrogen detected in the permanently shaded regions of the poles must be in the form of water-ice.”

Binder’s fellow researcher William Feldman allegedly added, “These data suggest an exciting scenario for lunar colonization. The polar regions that border the permanently shaded craters are also in the sunlight 80-85 percent of the time and would make optimal space station sites. The stations would have access to the water-ice and the sunlight would provide solar power. And by being near the poles you see Earth most of the time, which means you can communicate.”

I’m not a scientist. It sounds convincing when Feldman and Binder state clearly “We are certain we have found water” to Scientific American, MIT, and other reputable sources over a period of years (1998 – 2005 quotes are easily available on the internet).

This month’s LRO/Chandrayaan-1news is exciting. Yet I find it hard to stay with the excitement – or even with neutrality – because of the lousy track record human history has so far established when it comes to opening frontiers and/or colonizing new spaces. Though there are no indigenous peoples to wipe out, thank god, I don’t trust the old colonizing model of “empty space = automatic resource extraction.”

Back in 2005, I recall reading a story from WIRED magazine that described how the future of advertising could include satellite clusters projecting brand name shadows onto the moon. I can’t find the article electronically, but I remember feeling distressed for one simple reason: the technology to do the lunar advertising already existed even then, and the only reason it wasn’t happening was because decision-makers had the common sense to realize that the moon shouldn’t be divvied up like that. The moon is a commonly shared experience that can’t be monopolized for the uses of one tiny group of humans over others. It’s a location we all see, and a mass of rock that affects our tides, our wildlife, our traditions and cultures, probably even our physical selves – but it’s no one’s property. The thought of using the moon for advertising is nauseatingly offensive.

What are the practial, creative questions that need to be asked about colonizing the moon? We seem to be “playing well together” when it comes to the international cohabitation and exploration on Antarctica. Less harmony appears in the international discussions about the Polar North (possibly) opening up to shipping and exploration.

Would the challenge of building small settlements on the moon, in part thanks to the existence of moon ice, be a uniting project that keeps broad human goals above nationalistic ones? That question becomes more pressing, if – and I mean IF – it turns out the estimated 10 to 300 million metric tons (2.6 to 26 billion gallons) of ice possibly scattered across the moon’s poles is actually there – accessible, recoverable, and usable.

In the meantime, the breathtaking photographs of the Erlanger Crater and the very new insertion of Indian tech power into the international lunar discussion ripple through our cultural understanding how how humans relate to outer space. Maybe it’s up to artists, scientists, writers, musicians, athletes, to collaborate and discover the unique questions that need to be imagined for the unique place that the moon might offer us to visit.

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