Thousands of people stopped their daily activities on Friday July 19 to smile at the sky while the spacecraft Cassini took a picture of Earth from Saturn, which was revealed to the world on Monday.
In the Cassini images, taken 1.45 billion kilometers away, Earth and the moon can be distinctly seen between the rings of Saturn, Earth appearing as a pale blue dot, with a white and bright moon next to it.
“Cassini’s picture reminds us how tiny our home planet is in the vastness of space, and also testifies to the ingenuity of the citizens of this tiny planet to send a robotic spacecraft so far away from home to study Saturn and take a look-back photo of Earth,” said Linda Spilker, Cassini project scientist, in a statement.
The probe MESSENGER, also took a picture of the blue planet on the same day as Cassini from Mercury, at 98 million kilometers from Earth. In the MESSENGER images, Earth and the moon appear very large as the image is overexposed in order to capture as much light as possible. The images from the probe were also released on Monday by the U.S. National Aeronautics and Space Administration (NASA).
On Friday, NASA invited people to wave at Saturn while the spacecraft was taking pictures of the blue planet. It was the first time people on Earth had an advanced notice their portrait was being taken from interplanetary distance. Over 20,000 people around the world participated in the event sharing pictures and comments over the Internet.
“It thrills me to no end that people all over the world took a break from their normal activities to go outside and celebrate the interplanetary salute between robot and maker that these images represent,” said Carolyn Porco, Cassini imaging team lead at the Space Science Institute in Boulder, Colorado. “The whole event underscores for me our ‘coming of age’ as planetary explorers.”
Cassini was able to take the picture of Earth because the sun had temporarily moved behind Saturn from the spacecraft’s point of view. Taking pictures of Earth is in fact rare and difficult due to the planet’s close proximity to the sun. Scientists are currently assembling a wide-angle image of Earth which will be part of a multi-image picture of Saturn’s rings. Due to the difficulty of the task, the image will not be available before several weeks.
Picture credit: NASA/JPL-Caltech/Space Science Institute and NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington