A “gravity map” of Mars by NASA is offering a unique perspective of the Red Planet. Using years of data accumulated by numerous spacecraft that orbit Mars, the map allows us to see the insides of the planet.
NASA has offered an unprecedented view of Mars that’s akin to an X-ray, which allows us to peer inside the human body. Using gravitational anomalies experienced by NASA spacecraft as they soared above the Red Planet, NASA has collated the data and compiled the images into a unique map that exposes what lies beneath the surface of Mars.
Speaking about the gravity map through a statement released by NASA, Antonio Genova of the Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts said, “Gravity maps allow us to see inside a planet, just as a doctor uses an X-ray to see inside a patient. The new gravity map will be helpful for future Mars exploration; because better knowledge of the planet’s gravity anomalies helps mission controllers insert spacecraft more precisely into orbit about Mars.”
NASA spacecraft were able to sense the subtle differences in the gravitational field. Although relatively minuscule, the changing gravitational pull caused a change in the trajectory of the spacecraft. These differences were carefully measured, geotagged, and eventually compiled into a singular map of Mars, reported the Daily Mail. The entire exercise involved Mars Global Surveyor (MGS), Mars Odyssey (ODY), and the Mars Reconnaissance Orbiter (MRO). NASA estimates that it took about 16 years to carefully collate the data and compile the gravity map.
Although the gravity map could have been created using data obtained from a single satellite, three offered a very high degree of accuracy. Besides, the data-points were so small, the variation in the gravitational pull had to be re-verified through multiple inputs. Eventually, the NASA-MIT team required almost two years to scrutinize the data and develop the gravity map.
Why is the gravity map of Mars important? The map offers an entirely new perspective about the planet. The variation in gravitational pull is allowing the team to closely calculate the planet’s crust or upper land surface. Previous assumptions had to be quite vague due to limitations of the equipment, but this technique offers a much higher resolution of 75 miles, continued the statement.
“Like all planets, Mars is lumpy, which causes the gravitational pull felt by spacecraft in orbit around it to change. For example, the pull will be a bit stronger over a mountain, and slightly weaker over a canyon.”
Previous missions to Mars have also indicated that the planet has a liquid outer core of molten rock. Such geological formations can significantly impact the gravitational forces exerted by the planet over its circumference. Interestingly, the routine alteration of these forces over time has led the scientists to conclude three to four trillion tons of carbon dioxide freezes out of the atmosphere onto the northern and southern polar caps during a Martian winter, reported Gizmodo. Considering the mass of the entire planet, the gas alone makes up about 12 to 16 percent of the Martian atmosphere.
Apart from the atmosphere, the gravity map could offer new suggestions that explain the vast variation that’s easily observable in the southern and the northern hemisphere. While the southern highlands are heavily cratered, the northern lowlands are distinctively smoother, reported Fox News.
Mars is undoubtedly the planet that’s of highest importance not just to NASA, but other space agencies, including the European Space Agency and Russia’s Roscosmos. Recently, the European-Russian ExoMars program successfully sent two space probes to the Red Planet to confirm the presence of prehistoric life or Mars’ abilities to sustain inhabitation. NASA aims to send manned missions to Mars within the next 20 years, and a gravity map could be indispensable.
[Photo by Derek Berwin/Getty Images]