Back to the Moon

A rumpled, ice-gray word silently unrolls below the spacecraft — a stately, eerie unfolding of desolation beneath black space — crater rims followed by bright gouge marks, followed by more craters. A blue and white crest peeps over the horizon and floats upward, rising to show itself as Earth.

It is a view that lunar astronauts experienced between 1968 and 1972, yet this is not a film from the Apollo era. Instead, the high-resolution video was taken less than five months ago, on Sept. 30, 2008, by a Japanese moon orbiter named KAGUYA. The robot craft was launched on Sept. 14, 2007, from Japan’s Tanegashima Space Center.

KAGUYA has been taking spectacular videos of the moon, which JAXA, the Japan Aerospace Exploration Agency, has posted on YouTube. To watch the Earthrise video, CLICK HERE.

Several other videos are available, including some that apparently were pasted together from a series of measurements so that the viewer seems to buzz into and around craters in ways that no spacecraft could. But most are strictly documentary films, straight-line crossings of lunar scenery.

The probe’s objectives include studying gravity anomalies and searching for ice.

The findings from the gravity project are surprising, with pockets of less dense material on the far side and pockets of denser material on the side that faces Earth. According to a JAXA, this will cause scientists to rethink theories about the structure and evolution of the moon.

The moon undoubtedly was bombarded by comets, as was Earth. Comets, often dubbed “dirty snowballs” are believed responsible for all or most of our water. Perhaps cometary ice remains on the moon, not boiled off by the sun in craters that are permanently shadowed. If lunar ice could be extracted, it might provide water and air for a station.

The crater Shackleton, 13 miles across, overlaps the moon’s south pole and the sun never shines on parts of it. With sections always shielded from the sun, temperatures in the crater are in the range of 90 Kelvins, about -298 degrees Fahrenheit. Ice in the perma-shadows would remain rock hard. Radar signals bounced from the American probe Clementine, which went to the moon in 1994, “suggested that water-ice deposits existed inside the Shackleton Crater,” noted JAXA.

It adds that another American spacecraft, Lunar Prospector, indicated hydrogen gas may be around the south pole. Possibly the gas came from the decomposition of water ice.

But KAGUYA’s examination of the crater “indicates that exposed relatively pure water-ice deposits are lacking on the floor,” says JAXA in a press release dated Oct. 24, 2008. “Water-ice may be disseminated and mixed with soil in some areas, or may not exist at all.”

A definitive answer to whether ice is mixed with soil may come soon, with exploration by NASA’s Lunar Reconnaissance Orbiter. The LRO is scheduled for launch on April 24. Its seven instruments will check “the moon’s topography, lighting conditions, mineralogical composition and natural resources,” says a NASA press release issued a week ago.

“The polar regions of the moon are the main focus of the mission because continuous access to sunlight may be possible and water ice may exist in permanently shadowed areas of the poles.”

The space agency considers the LRO to be one of the first steps toward returning astronauts to the moon. KAGUYA’s videos, and the findings by the LRO, seem likely to reawaken a sense of excitement about exploring our nearest neighbor in space.

In the meantime, the views also instill a feeling best expressed by Cory, my wife, when she saw the video of Earthrise. “We have this beautiful, wonderful planet,” she exclaimed. “We’ve gotta take care of it.”

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