NASA’s Curiosity rover has supplied scientists with surprising perception into the gravity on Mars by utilizing the rover’s sensors as a makeshift gravimeter.
The Curiosity rover has accelerometers for measuring acceleration and gyroscopes for measuring orientation and angular velocity on board, similar to the sensors in a smartphone which inform you the place you’re on a map and through which path you’re going through. The very correct sensors on the Curiosity are used to navigate the floor of Mars and level its different devices in the precise path. Whereas these devices weren’t designed for measuring gravity, scientists realized that they might use them to assemble information on the mountain that Curiosity is presently exploring, known as Mount Sharp.
The inspiration for the gravity measurement approach got here from a lunar mission virtually 50 years in the past. Again on the Apollo 17 mission to the Moon in 1972, astronauts had been in a position to measure the lunar gravity utilizing a device that they had on board their buggy known as a gravimeter. Whereas there aren’t any astronauts to gather information on Mars, researchers realized that there have been instruments within the Curiosity that they might mix collectively to get the identical details about Mars as that they had on the moon.
Aspect-by-side pictures depict NASA’s Curiosity rover (left) and a moon buggy pushed through the Apollo 16 mission. NASA/JPL-Caltech
Mount Sharp is likely one of the largest mountains on Mars, and it’s positioned surprisingly throughout the enormous 96-mile-wide Gale Crater. The mountain rises 18,000 ft from the crater’s ground, and scientists nonetheless aren’t certain the way it developed, although they assume it might be because of the crater having been crammed with sediment and compacted downwards.
When the Curiosity is stationary, the accelerometers detect the gravitational pull of the planet on the rover. And when Curiosity is ascending a slope, because it has been since 2014, researchers can see how a lot extra gravity is added by the mountain. The reply seems to be lower than anticipated, which means that Mount Sharp is much less dense than beforehand believed.
“The decrease ranges of Mount Sharp are surprisingly porous,” lead researcher Kevin Lewis of Johns Hopkins College stated in an announcement. “We all know the underside layers of the mountain had been buried over time. That compacts them, making them denser. However this discovering suggests they weren’t buried by as a lot materials as we thought.”
“To me, Mars is the uncanny valley of Earth,” he added. “It’s comparable however was formed by completely different processes. It feels so unnatural to our terrestrial expertise.”
The findings are revealed in Science.