Volcanoes on the ocean floor flare up on regular cycles - lasting from two weeks to 100,000 years. Do they help produce suddenly seesawing hot and cold periods?
A panoramic view of the desert world next door, from one of the highest elevations reached by the Mars rover Opportunity in its 11 years on the Red Planet.
The EarthSky team has a blast bringing you daily updates on your cosmos and world. We love your photos and welcome your news tips. Earth, Space, Sun, Human, Tonight. Since 1994.