It's not clear what NASA will first send to Europa.
It could be a spacecraft similar to Cassini that will repeatedly fly past the moon, sending back information about it. However, the first mission also could be a spacecraft that will go into orbit around Europa, studying its surface, the geyser and gases.
After that mission, whatever it might entail, sends back data, NASA will send another robot — one that will likely land on Europa's ice shell.
"We're in the process of studying it," said Green. "Now that we're seeing the plumes, we have new ideas we never had before. We're in the pre-formulation phase. We're bringing the ideas together and figuring out what that first mission might be. There'll be a series of robotic missions."
Using current rocket technology, it would probably take eight to nine years for a spacecraft to reach Europa. However, if NASA uses one of the new heavy-lift rockets it's been working on, that trip could be shortened to two years.
NASA scientists speculate there might be life currently on Europa and are planning the first of a series of robotic missions to study Jupiters moon.
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