During his yearlong mission aboard the International Space Station, Scott Kelly traveled over 143 million miles in orbit around Earth.
On average, Mars is 140 million miles away from our planet.
Coincidence? Well, basically.
NASA astronaut Scott Kelly took this selfie with the second crop of red romaine lettuce in August 2015. Research into things like replenishable food sources will help prepare the way for Mars. (And the red lettuce even kind of matches the Red Planet!)
There’s nothing average about a trip to Mars; so of course you don’t travel an “average distance” to get there. Launches for robotic missions – the satellites and rovers studying Mars today – are timed around when Earth and Mars are about a third of that distance, which happens every 26 months.
While the shortest distance between two points is a straight line, straight lines are hard to do in interplanetary travel. Instead, Mars missions use momentum from Earth to arc outward from one planet to the other. The Opportunity rover launched when Earth and Mars were the closest they’d been in 60,000 years, and the rover still had to travel 283 million miles to reach the Red Planet.
On the International Space ...