Cape Canaveral, Fla. ? NASA’s upcoming mission to Jupiter can’t get much greener than this: a solar-powered, windmill-shaped spacecraft.

The robotic explorer Juno is set to become the most distant probe ever powered by the sun.

Juno is equipped with three tractor-trailer-size solar panels for its 2 billion-mile journey into the outer solar system. It will be launched Friday morning aboard an unmanned Atlas V rocket — barely two weeks after NASA’s final space shuttle flight.

The shuttle’s demise is giving extra oomph to the $1.1 billion voyage to the largest and probably oldest planet in the solar system. It’s the first of three high-profile astronomy missions coming up for NASA in the next four months.

Jupiter — a planet several NASA spacecraft have studied before — is so vast it could hold everything else in the solar system, minus the sun. Scientists hope to learn more about planetary origins through Juno’s exploration of the giant gas-filled planet, a body far different from rocky Earth and Mars.

“Look at it this way — it is a new era,” said Jim Green, NASA’s director of planetary science. “Humans plan to go beyond low-Earth orbit. When we do that, it’s not like ‘Star Trek.’ It’s not ‘go where no man has gone before.”‘

Plunging deeper into space will require robotic scouts first, he said.

Southwest Research Institute astrophysicist Scott Bolton, Juno’s principal investigator, said it’s also important for people to realize “NASA’s not going out of business.”

“If we’re going to learn who we are and where we came from, and how the Earth works, we’ve got to keep doing these science missions, not just Juno,” Bolton said.