samschooler
The fourth photo is Olympus Mons, not a volcano on Mars; it is the volcano on Mars. I'm sure a lot of you know this, however reminding myself of how big this peak is is always breathtaking. A hypothetical ascent in our future would be the single largest climbing feat human kind ever could undertake in our known solar system [0].

Mt. Everest is 8,848.86 m (29,032 ft) [1].

Mauna Kea (assuming you're climbing from the local bottom of the ocean is 9,330 m (30,610 ft) [2].

Olympus Mons' prominence is 21,900 m (71,850 feet 4.724 inches) [3].

Try climbing Everest, twice, where the entire mountain (and planet) is the "death zone" and your supplies have to be flown in from one planet over.

Edit: Also! For a sense of scale, the crater in the photo is 85 km (53 miles) in diameter [4]. About the distance from the Taco Bell in Half Moon Bay to the Taco Bell just east of Santa Cruz as the crow flies [5].

[0]: https://en.wikipedia.org/wiki/List_of_tallest_mountains_in_t...

[1]: https://web.archive.org/web/20201208113343/https://www.natio...

[2]: http://www.ngs.noaa.gov/cgi-bin/ds_mark.prl?PidBox=TU2314

[3]: https://tharsis.gsfc.nasa.gov/mola.summary.pdf

[4]: https://www.britannica.com/place/Olympus-Mons

[5]: https://www.gaiagps.com/map/?loc=8.6/-122.6459/37.2976&pubLi...

johncarlosbaez
Strange title, since we've known for a long time that Mars has an atmosphere unlike our own.