If you want to have a starship captain’s view of flying past the Earth, then NASA is happy to oblige. This week, the space agency released a video made of images taken by the Juno space probe as it shot past our planet last October. The unmanned spacecraft was using the Earth’s gravity to build up its velocity by over 8,800 mph (14,100 km/h) and slingshot it on its way to Jupiter. And as it did so, it took the time to receive a “Hi” from ham radio operators back home.
On October 9, at 3:21 PM EDT, the US$1.1 billion Juno probe passed within 347 mi (559 km) of Earth as it hurtled over South Africa. It had already made an epic voyage of over 879 million mi (1.4 billion km) since it launched in 2011. Its trajectory took out beyond the orbit of Mars and then back to Earth in a maneuver designed to build up enough speed to send it to Jupiter, where it will orbit the planet after reaching it on July 4, 2016, on a mission to study the giant planet’s atmosphere.
When the start of the video was made, Juno was still 600,000 mi (966,000 km) away from Earth and was turning at two revolutions per minute. The images that make up the footage were taken by four cameras normally used for orienting the magnetic sensors for the Magnetic Field Investigation (MAG) experiment on the spacecraft's giant solar panels. These cameras calculate the position of the panels by looking at faint stars as landmarks. Since these low-resolution cameras weren’t meant for filmaking, putting together the frames for the video required planning and exact timing.
"If Captain Kirk of the USS Enterprise said, ‘Take us home, Scotty,’ this is what the crew would see," says Scott Bolton, Juno principal investigator at the Southwest Research Institute, San Antonio. "In the movie, you ride aboard Juno as it approaches Earth and then soars off into the blackness of space. No previous view of our world has ever captured the heavenly waltz of Earth and moon."
While Juno made its flyby, amateur radio operators around the world beamed "Hi" (or specifically ".... .." in Morse code) to the spacecraft. This was picked up by Juno’s Waves instrument, which is designed to measure the Jovian magnetosphere’s radio and plasma waves. Later, the spacecraft retransmitted the message to Earth. NASA then cleaned up the message’s radio noise and produced a video presentation of it.
The final video of the Juno flyby includes an original score by Vangelis – check it out below.