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Stardust finishes comet mission
Source: Agencies |
February 16, 2011, Wednesday
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A NASA spacecraft zipped past a comet half the size of Manhattan in a Valentine's Day rendezvous that scientists hope will shed light on these icy solar system bodies.
Speeding at 38,600kph, Stardust zoomed by comet Tempel 1 on Monday night, snapping six dozen high-resolution pictures along the way. At nearest approach, the craft passed within 180 kilometers of the potato-shaped comet - closer than the original prediction.
Instead of erupting in cheers, mission controllers at the NASA Jet Propulsion Laboratory puzzled over why images from the flyby were not downloading in order.
NASA had planned to wow the world by playing back the images in reverse order, starting with five close-up shots of Tempel 1's nucleus. Instead, the first images to pop up showed the comet as a tiny speck.
"We still don't understand fully why this didn't work the way we planned," said Chris Jones, an associate director at the Jet Propulsion Laboratory, which managed the mission.
All the pictures were stored aboard Stardust. "They're not lost," Jones said.
The glitch means scientists will have to wait several more hours for everything to download to study changes on the comet's surface.
The flyby, which occurred 338 million kilometers from Earth, is the second time Tempel 1 has been visited up close.
Onboard dust detectors revealed Stardust took several hits as it swooped past Tempel 1. The craft is armed with bumpers designed to protect it from comet shards as large as half an inch.
"We made it through," said mission control commentator Mykal Lefevre, of Lockheed Martin Space Systems in Denver.
Shortly after the closest approach, Stardust turned its antenna toward Earth to begin the downlink. The playback was delayed an hour due to inclement weather at a ground station in Spain.
When the close-up images didn't show up as planned, project leaders were seen pacing around mission control or huddling in groups to troubleshoot.
Comets are like frozen time capsules because they're thought to contain primordial material preserved from the aftermath of the solar system's birth some 4.5 billion years ago. Studying comets could yield clues to how the sun and planets formed.
Speeding at 38,600kph, Stardust zoomed by comet Tempel 1 on Monday night, snapping six dozen high-resolution pictures along the way. At nearest approach, the craft passed within 180 kilometers of the potato-shaped comet - closer than the original prediction.
Instead of erupting in cheers, mission controllers at the NASA Jet Propulsion Laboratory puzzled over why images from the flyby were not downloading in order.
NASA had planned to wow the world by playing back the images in reverse order, starting with five close-up shots of Tempel 1's nucleus. Instead, the first images to pop up showed the comet as a tiny speck.
"We still don't understand fully why this didn't work the way we planned," said Chris Jones, an associate director at the Jet Propulsion Laboratory, which managed the mission.
All the pictures were stored aboard Stardust. "They're not lost," Jones said.
The glitch means scientists will have to wait several more hours for everything to download to study changes on the comet's surface.
The flyby, which occurred 338 million kilometers from Earth, is the second time Tempel 1 has been visited up close.
Onboard dust detectors revealed Stardust took several hits as it swooped past Tempel 1. The craft is armed with bumpers designed to protect it from comet shards as large as half an inch.
"We made it through," said mission control commentator Mykal Lefevre, of Lockheed Martin Space Systems in Denver.
Shortly after the closest approach, Stardust turned its antenna toward Earth to begin the downlink. The playback was delayed an hour due to inclement weather at a ground station in Spain.
When the close-up images didn't show up as planned, project leaders were seen pacing around mission control or huddling in groups to troubleshoot.
Comets are like frozen time capsules because they're thought to contain primordial material preserved from the aftermath of the solar system's birth some 4.5 billion years ago. Studying comets could yield clues to how the sun and planets formed.
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