The seasons on Mars are like exaggerated versions of those on Earth. They have the same cause: their planet’s tilt on its axis. And they have the same cadence: summer in the northern hemisphere is longer than summer in the south. But they’re a whole lot longer.
Today marks the start of northern summer on Mars. It will last 183 Earth days. By comparison, southern summer lasts only 158 Earth days.
Both Earth and Mars are tilted at an angle of about 23 degrees. So as they orbit the Sun, their poles take turns dipping toward the Sun. It’s summer for the hemisphere that nods toward the Sun, and winter for the hemisphere that tilts away from it.
Earth and Mars follow stretched out orbits. Each planet is closest to the Sun in northern summer, and farthest during southern summer. A planet moves more slowly when it’s farther from the Sun, stretching the season that’s in progress then: in this case, northern summer.
One difference between the seasons on Earth and Mars is that Mars’s orbit is much more lopsided, so there’s a much bigger swing in seasonal temperatures. On Mars, summers in the northern hemisphere are cooler than those in the south. And northern winters are much warmer. So if you’re looking for more temperate conditions on Mars, the northern hemisphere is the place to be.
Mars is lost in the Sun’s glare now. It’ll pass behind the Sun in October, then return to view in the dawn sky around Thanksgiving.
Script by Damond Benningfield