TCS Daily


In the Beginning...

By Charles Matthew Rousseaux - September 8, 2004 12:00 AM

"I'm gonna soak up the sun. Gonna tell everyone to lighten up."

-- Sheryl Crow

NASA's Genesis probe has been soaking up the sun for the better part of the last three years, although it doesn't have much of a burn -- probably because it's been doing so in the deep freeze of outer space. Assuming that it doesn't crash (or burn) during its return to the Earth this Wednesday, Genesis is gonna lighten up the brains of scientists searching for a better understanding of the formation of the solar system.

Genesis' descent will be the first time samples have returned from beyond the Moon -- samples haven't been sent back from the Moon since 1972 (the rumor that those rocks were coated in tie dye are not true, but they were pretty groovy baby). The samples don't amount to much, just a few burned bits of the solar wind.

The solar wind streams away from the sun's screamingly hot outer layer, its corona. Like the sun itself, the solar wind consists largely of hydrogen and helium, but there are other elements as well, including oxygen and its isotopes. (Isotopes are heavier or lighter versions of the same element. Think Arnold Schwarzenegger and Danny DeVito in the movie "Twins.") To capture those sizzling particles in pure form, the core of the Genesis craft was crusted with jewels -- wafers of pure diamond, sapphire, silicon and gold.

That pricey particle prison was not sufficient to ensure that only the sun's pure substance would be soaked up. To do that, Genesis' mission planners had to go to great lengths -- literally. To prevent contamination they assembled Genesis in an ultra clean room, and regularly washed it with pure nitrogen. They then sent the craft about 1 million miles from the earth, to Lagrange Point 1 (L-1), where the gravity of the earth and sun are equally balanced. L-1 is far enough away that the earth's magnetic field will not taint any of the samples.

To prevent Genesis' clamshell case from cracking during a rough landing, the craft simply won't land. Instead, during its decent over the U.S. Air Forces' Utah Test and Training Range, it will deploy a large rectangular parachute, which will be snagged by a hook-tipped pole carried by a helicopter. Once the craft has been caught, it will be set down gently and then flown to NASA's Johnson Space Center for intense study. While the Air Force has successfully snagged many capsules from spy satellites via airplane, this will be the first time that a helicopter capture has been attempted. (Coincidentally, "Corona" was the name of the spy satellite retrieval program. Presumably, plenty of Coronas will be passed around after the son of Corona returns with some of the sun's corona.)

Genesis won't be returning with much. Over the course of its mission, it has only collected about 10-20 micrograms of solar wind -- the equivalent of a few grains of salt.

As with so many other space missions, Genesis' quest seems in equal measure exotic, heroic and quixotic. After all, why send a dining room-table sized craft on a $264 million round-trip mission of about 2 million miles, capped with a helicopter capture that literally requires the services of Hollywood stuntmen, in order to return with a few fried grains of the sun?


The answer goes to the craft's name. Although Phil Collins might be disappointed, it wasn't called Genesis because it spent years soaking up the sun's invisible touch. Rather, the cooked grains that Genesis is coming back with may hold the keys -- and will certainly hold clues -- to the formation of the solar system.

Scientists aren't sure of the exact ratios of the elements that were in the solar system when it condensed out of a vast cloud of dust and gas about 4.6 billion years ago. The ratios of those elements have been altered elsewhere in the solar system. However, the sun's outer layers almost certainly consist of the pristine forms of that primordial stuff.

Scientists will compare the ratios of the elements in the samples Genesis brings back with the ratios of those elements from other places in the solar system -- particularly the ratios of the isotopes of oxygen. Doing so should help them hone their theories about how this solar system formed.

That knowledge is likely to have even further-out applications as well. Scientists have detected more than 100 planets outside the solar system -- just last week, two teams announced the discovery of three worlds far smaller than any previously found. One of them was found in 55 Cancri, which is known to have three other planets around it. The few fried grains aboard Genesis may eventually help scientists determine how those distant places formed.

Genesis is only the first of what scientists hope will be several happy returns of space substances. Samples of Comet Wild 2, captured by the Stardust spacecraft, are scheduled for a rendezvous with the earth in January of 2006. Last year, Japan launched a sample-return craft towards an asteroid, which is scheduled to return in 2007.

Now that the summer is over, it's probably appropriate that scientists will be spending long days of labor indoors, studying what Genesis has soaked up from the sun.

Charles Rousseaux is the speechwriter for Interior Secretary Gale Norton. The views expressed are his own.


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