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What Is the Surface Gravity on Mars?

The fourth planet from the sun, Mars has transfixed scientists for centuries. Its name comes from the Roman god of war, and it was given to the planet because its iron-rich, red surface is reminiscent of blood. Scientists today study Mars because there is tantalizing evidence of water beneath its surface. Many wonder if Mars, with seasons and gravity similar to Earth, could be the next planet colonized by humans.

Definition of Gravity
- Gravity isn't a force; it's the bending of space and time. Picture space and time like a big blanket. If you stretch the blanket out and hold it above the ground and then place a basketball in the middle, the ball will create a depression in your space time blanket. If you then release a marble at one edge of the blanket, it will roll toward the basketball, but the basketball doesn't pull it; the depression and curve of the blanket guide its trajectory. Gravity is weak, but it affects every part of your life.
Martian Gravity
- Mars is much smaller than Earth; its diameter is about half of Earth's diameter. Earth is 10 times as massive and about 20 percent more dense. These differences make the gravity of Mars about 38 percent that of Earth. So if you weighed 170 lbs. on Earth, you'd weigh only about 64 lbs. on Mars.
Effects of Zero Gravity on the Human Body
- Our bodies were designed to work within the construct of Earth's gravity. Removing that gravity causes serious changes in how our bodies function. Astronauts in space experience dehydration due to the redistribution of fluid in their bodies. Gravity normally keeps fluid in the lower part of our bodies. With no gravity, fluid rises and the brain reacts by getting rid of the fluid. Since our hearts don't have to move blood against the pull of gravity, they start to beat slower. Bone and muscles begin to atrophy without gravity's pull to keep them strong.
Mission to Mars
- With the continued destruction of Earth's habitats, scientists are looking to Mars as the next place for humans to colonize. One of the many problems astronauts will face during a manned mission to Mars is gravity. Depending on the type of mission, astronauts could spend anywhere from 400 to 650 days in space with only 30 to 90 of those days on the Martian surface. While there is no hard data, scientists agree that tackling the problem of going from Earth's gravity, to zero gravity, to Martian gravity and then back is key to a successful mission.
Mars Gravity Biosatellite
- The Mars Gravity Biosatellite is a joint venture of MIT and the Georgia Institute of Technology. The planned research satellite will launch 15 mice into a low Earth orbit to simulate the gravity found on Mars. Students hope to study the effects of Martian gravity on mammals to provide important information for a future manned mission to Mars.

Astronomy