Olympus Mons Martian surface atmospheric pressure is less than one percent of Earth's, the much lower gravity of Mars increases the atmosphere's scale height; in other words, Mars's atmosphere is expansive and does not drop off in density with height as sharply as Earth's. The composition of Olympus Mons is approximately 44% silicates, 17.5% iron oxides (which give the planet its red coloration) 7% aluminum, 6% magnesium, 6% calcium, and particularly high proportions of sulfur oxide with 7%. These results point to the surface being largely composed of basalts and other mafic rocks, which would have erupted as low viscosity lava flows
Doom Mons Titanean "mountains" are little more than hills. However, some of these mountains rise to some several hundreds of meters high. Doom Mons is currently believed to be possibly the largest Titanean mountain range and with the eponymous peak one of the highest; the title of highest peak on Titan is thought to be held by the Mithrim Montes, which may have been formed by global contraction. Doom Mons is believed to be a twin-peak that rises above the relatively flat surrounding plain, and a probable massive cryovolcano. It has a 500–600 m deep indentation on its western side, containing a