June 30, 2004
Saturn looming
NASA's Cassini-Huygens planetary probe should be passing through the rings of Saturn tonight. If all goes well, we'll have the first imagery in the morning. You can watch a live webcast from JPL.
As noted earlier this week, this is a risky moment, but there's much more to come.
This week, Cassini will pass through two of Saturn's outermost rings and sweep into the orbit of a planet that has been the subject of earthly speculation for nearly four centuries. It will be a tense moment for the scientists and engineers of the $3.3 billion Cassini-Huygens Mission, more than 20 years in the planning.Over the next four years, as the spacecraft flies in 76 planned orbits around the planet, scientists will study its curiously skewed magnetic field, gather the first close-up images of six of its iciest moons, and examine the wind-whipped, pastel-hued surface of the planet itself.
The highlight will come in December, when Cassini's passenger craft, called Huygens, will be deployed to probe Saturn's largest moon, which may bear unexpected clues to the origin of life on Earth.
At precisely 7:36 p.m. Pacific time on Wednesday, Cassini's main engine will fire for 96 minutes to send the 5,400-pound spacecraft flying between Saturn's "F" and "G" rings. There it will be captured by Saturn's gravity, achieve its first orbit, and begin its primary mission.
Meanwhile, a risky spacewalk outside the International Space Station paid off.
Determined to do better than last week, the international space station's two astronauts ventured back outside today on an unusually risky spacewalk and successfully replaced a bad circuit board.Posted by Alan at June 30, 2004 10:27 PMShouts of "hurray!" and "great!" emanated from space after American Mike Fincke and Russian Gennady Padalka learned their effort had paid off.
"Great job, you guys," Mission Control radioed.
"We're glad to be able to be of service," Fincke said.
It was a long and potentially dangerous haul to the repair location. Fincke and Padalka had to cross nearly 100 feet to get to the fried circuit breaker -- a grueling distance for spacewalkers over difficult terrain. Then they managed to pry off the cover for the row of circuit breakers; it was stiff and incredibly hard to move.
Last Thursday, they barely made it out the hatch when their spacewalk was aborted, just 14 minutes after it began. An oxygen-flow switch on Fincke's suit did not lock into the proper position and oxygen gushed out of his tank, prompting flight controllers to order the spacewalkers back inside.