Tiffany Day is one of our astronomy guides and in this post she discusses robotic explorers of our Solar System and beyond.

If you’ve been paying attention to recent space news, you would have heard that the New Horizons space probe completed a successful flyby of Pluto – our first ever high resolution view of the planet in the history of our species – back in July of this year, or that the Curiosity rover successfully landed on Mars three years ago, and has just recently provided the first hard evidence of liquid water on Mars.

But how many space craft do we actually have out there in the Solar System right now?

The list is quite extensive, but it depends on whether we count space craft from which we are no longer receiving data or not. If we count only active probes and rovers, this handy little graphic from chartgeek.com provides a comprehensive list at a glance.

Here we see that the planet Mars is by far the object we’ve visited the most, with two active rovers – Opportunity and Curiosity – and three orbiting satellites currently sending data from the rusty planet back home to Earth. Our own Moon is the next most actively observed object, with three orbiting satellites collecting data. Voyager 1, launched in 1977, is our winning space craft in terms of distance from Earth, now just leaving our Solar System for the first time ever in history.