Olympus Mons: 10K

Welcome to Olympus Mons, Recon 5, it's a beautiful day on Mars. You're going to run to the top of the highest mountain in the solar system! That's a distance of almost 200km, and a climb of 22km.

You've just climbed a cliff that's almost 8km tall, about the same height as Mount Everest! The outer edge of Olympus Mons is surrounded by this escarpment, the only shield volcano on Mars that has this! Now you're properly on the volcano, the incline should become much gentler.

Mars is only half the diameter of Earth, so the Horizon is only 3km away, and Olympus Mons is the size of Italy, you won't get much of a view. Not a great photo spot!

In 1979, an Italian astronomer, Giovanni Schiaparelli noticed that the mountain was one of the few things that could be seen during the dust storms of Mars. He names it Nix Olympica, after the home of the Greek gods. Appropriate, since lightning was detected on Mars in 2009!

Olympus Mons is so high because of the lower gravity of Mars and because Mars didn't have mobile plate tectonics when it formed. It's hundreds of millions of years old, but the most recent lava flows look to be about 2 million years old, meaning it might still be active occasionally.

Your normal running gait won't work well on Mars due to the lower gravity. The Apollo astronauts developed the 'Apollo Stride' to walk on the moon, which more resembles the gait of a long-distance skier.

No probes or rovers have visited Olympus Mons due to the dust, which obscures the underlying bedrock making it hard to get samples. It's also very fine and could wear down delicate machinery. The spots on Mars that could have harboured life or water tend to be at lower altitudes, and that's what researchers tend to be interested in.

The air is getting very thin, and the sky is almost completely black. Atmospheric pressure here is just 72 pascals, compared to 600 pascals lower down on the surface, and 100,000 pascals on Earth. Some scientists believe that Mars used to have a thicker atmosphere and large oceans of water, which were stripped away when Mars lost its magnetic field.

Mars is not exactly hospitable, but some would like to change that through terraforming. The first thing would be to warm the planet up, potentially using mirrors to reflect more light onto its surface. If they aim them at the ice caps, that would also release carbon dioxide and CFCs into the atmosphere which would speed up the process. They'd then need to use bacteria and algae which consume carbon dioxide and release oxygen to make the air breathable. It might make it a pleasant place to live... in a few hundred or thousand years!

At the top of Olympus Mons are six calderas; craters formed when the top of the volcano caves in. Going into one would be a 3km descent!

Just 500m from the summit!

Congratulations! You've reached the top. As late as the 1900s, humans saw 'canals' on Mars and thought there was a thriving alien civilisation. We know more about Mars today, but we still have so much to discover!