NASA'S Curiosity rover on Mars successfully captured images of Mercury as it made its way in front of the Sun.
These images were the first taken of the smallest planet of the Solar System from a planet other than Earth. They were also the first captured from Mars' viewpoint. Since Curiosity took the pictures from a great distance, these pictures depicted Mercury as a tiny dot passing in front of the Sun, creating an empirical observation of its orbital path.
Curiosity used its two-eyed Mast Camera with a telephoto camera attached to it to document Mercury passing the Sun.
"This is a nod to the relevance of planetary transits to the history of astronomy on Earth," Mark Lemmon of Texas A&M University, College Station, Mastcan science team member explained in a press release. "Observations of Venus transits were used to measure the size of the solar system, and Mercury transits were used to measure the size of the sun."
The images were taken on June 3, 2014. During that time, the rover was on the Gale Crater of the Red Planet. Aside from showing Mercury's path as it crossed in front of the Sun, it also showed at least two sunspots, both of which were as big as our planet. The sunspots followed the rotation of the Sun at a much slower pace than Mercury's movements.
In June 2012, Venus was seen from Earth making its transit in from the Sun. According to the scientists, a Mercury transit would be visible on Earth in May 9, 2016. The transits of Mercury and Venus were the most often viewed transits from our planet, but Mars could also be a viewing point from which one can watch Earth's movement.
Curiosity's main mission on the Red Planet was to look for clues regarding the ancient habitable environments that once flourished in Mars.
