Juno broke a Guinness World Record: Fastest craft ever

Before NASA’s spacecraft Juno fired its engine on July 4 to slow it and place it in Jupiter’s orbit, the probe was zipping through space at a speed so fast it's hard to comprehend. And now, Guinness World Records has announced that the basketball court-sized spacecraft is a record-holder: it’s the fastest spacecraft ever.

It was traveling at a mind-boggling 165,000 miles per hour (measured relative to Earth) prior to a 35-minute engine burn, which slowed the craft down by 1,212 mph. Guinness World Records said that the record Juno shattered was first set four decades ago by a craft called Helios 1.

After its launch in August of 2011, Juno traveled 1.7 billion miles to reach Jupiter. And it turns out that its patriotic orbital insertion date of July 4 is actually a coincidence, according to NASA.

The craft is now in orbit around the gas giant— our solar system’s largest planet— and takes about 53 days to complete one loop around it. But starting in October, Juno will begin to make shorter orbits of 14 days each, when the space agency will start studying the science of the planet, all while braving high levels of radiation and cruising close to its clouds.

The solar-powered Juno will explore the planet’s magnetic field and composition, working on mysteries like whether or not it has a core. And since Jupiter is such an ancient planet, scientists hope that understanding the gas giant will help them unlock secrets of our solar system’s formation.

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