US: Nasa's Juno spacecraft buzzes Jupiter moon Europa, closest in years

Nasa’s Juno spacecraft has made the closest approach to Jupiter’s tantalising, icy moon Europa in more than 20 years.

On Thursday, Juno zipped within approximately 352km of Europa — thought to have an ocean flowing beneath its thick frozen crust — raising the possibility of underwater life. Scientists hailed the flyby as a success, with four pictures beamed down and released within several hours.

Scientists had hoped to observe possible water plumes shooting from the surface of Europa, close in size to Earth's moon. But none were immediately visible in the initial look.

“We have to be at the right place at just the right time," Juno's chief scientist, Scott Bolton of the Southwest Research Institute in San Antonio, said in a statement.

John Bordi, deputy mission manager at Nasa’s Jet Propulsion Laboratory, expected the spacecraft to go “screaming by pretty fast”, with a relative velocity of almost 23.6 kilometres per second.

The first photo from the flyby is a close-up of Europa's equatorial region, criss-crossed by ridges, troughs, and possibly an impact crater.

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