NASA is about to discover how solar heat devours a comet.
"For the first time, we'll see the same comet before and after its closest approach to the sun," explains Joe Veverka, principal investigator for NASA's Stardust-NExT mission.
The comet is Tempel 1, which NASA's Deep Impact probe visited in 2005. Now another NASA spacecraft, Stardust-NExT, is closing in for a second look on Valentine's Day, Feb. 14, 2011. The two visits bracket one complete orbit of the comet around the sun--and a blast of solar heat.
"Close encounters with the sun never go well for a comet," says Veverka. "Fierce solar heat vaporizes the ices in the comet's core, causing it to spit dust and spout gas. The cyclic loss of material eventually leads to its demise."
Researchers suspect the flamboyant decay doesn't happen evenly all over a comet's surface*, but until now they've lacked a way to document where, exactly, it does occur. Stardust NExT will image some of the same surface areas Deep Impact photographed 6 years ago, revealing how these areas have changed and where material has been lost.
"Deep Impact gave us tantalizing glimpses of Temple 1," says Veverka. "And we saw strange and unusual things we'd like a closer look at."
At a January 2011 press conference, Veverka and other Stardust-NExT team members listed the features they're most interested in seeing again:
For starters, parts of the comet's surface are layered like pancakes.
"Earth has layers because water and wind move dirt and debris around here, but layering on a comet was a surprise – and a mystery," says Veverka.
"For the first time, we'll see the same comet before and after its closest approach to the sun," explains Joe Veverka, principal investigator for NASA's Stardust-NExT mission.
The comet is Tempel 1, which NASA's Deep Impact probe visited in 2005. Now another NASA spacecraft, Stardust-NExT, is closing in for a second look on Valentine's Day, Feb. 14, 2011. The two visits bracket one complete orbit of the comet around the sun--and a blast of solar heat.
"Close encounters with the sun never go well for a comet," says Veverka. "Fierce solar heat vaporizes the ices in the comet's core, causing it to spit dust and spout gas. The cyclic loss of material eventually leads to its demise."
Researchers suspect the flamboyant decay doesn't happen evenly all over a comet's surface*, but until now they've lacked a way to document where, exactly, it does occur. Stardust NExT will image some of the same surface areas Deep Impact photographed 6 years ago, revealing how these areas have changed and where material has been lost.
"Deep Impact gave us tantalizing glimpses of Temple 1," says Veverka. "And we saw strange and unusual things we'd like a closer look at."
At a January 2011 press conference, Veverka and other Stardust-NExT team members listed the features they're most interested in seeing again:
For starters, parts of the comet's surface are layered like pancakes.
"Earth has layers because water and wind move dirt and debris around here, but layering on a comet was a surprise – and a mystery," says Veverka.
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