Mars and NASA space probe MAVEN

NASA’s MAVEN Dodges Hurtling Mars Moon: Space Probe Avoids Crash By Seconds

NASA took precautionary measures this week to avoid its MAVEN orbiter spacecraft becoming so much space junk as it and Mars’ speedy little moon Phobos were moving toward what appeared to be a point of intersection, space agency officials announced. Should the MAVEN spacecraft have maintained its appointed orbital movement, the tiny orbiter, and the substantially larger moon may have attempted to occupy the same area of space at the same time, an occurrence that would have had an unfortunate outcome for the NASA science satellite.

According to the Daily Mail, Flight controllers who operate the MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft out of NASA’s Jet Propulsion Laboratory in Pasadena, California, sent the signal to the craft, which is orbiting Mars to study its atmosphere, to engage its engine to give itself enough momentum to steer clear of the hurtling potato-shaped rock that is Phobos, which measures about 10 by 14 miles by 11 miles (16 by 22.5 by 18 kilometers, respectively). Turning on the engine, called a “rocket motor burn” by NASA in its announcement, gave MAVEN an increase in acceleration of 1.3 feet per second (0.4 meters per second), just enough to push the space probe, which measures 37.5 feet (11.4 meters) at its widest, out of Phobos’ way.

The small moon, which is the largest of Mars’ two captive planetoids, flies around the Red Planet in an egg-shaped orbit at 1.3 miles per second (2.1 kilometers per second), swinging around the red world three times in a day.

Mars and its largest moon Phobos
Phobos is the closest orbiting moon to its parent planet in the Solar System. [Image by Nostalgia For Infinity/NASA/Shutterstock]

This is the first time NASA has had to move MAVEN to avoid a collision.

NASA said in its statement that moving MAVEN was necessary after it became clear to those monitoring the orbital path of the orbiter that it would come within seven seconds of reaching the point in space that would also be occupied by Phobos on its orbital swing. The orbits of the two cross several times a year, the space agency noted, but at no time have they ever come so close as to prompt the space probe to be moved. Given Phobos’ size (NASA’s algorithms consider the moon at 30 kilometers in diameter, just to be on the safe side), moving MAVEN out of the way seemed the best option.

The rocket motor burn was executed to place MAVEN roughly 2.5 minutes away from Phobos as it flew past.

The maneuver was accomplished on Thursday, March 2. The avoided impending — and now negated — crash was calculated to occur on Monday, March 6.

Among the important data gathered, MAVEN lists as one of its accomplishments the detection of the deterioration of Mars’ atmosphere, which was found to increase significantly during solar storms. As reported in November 2015, the atmospheric loss to space was likely a major factor in Mars’ gradual shift from a carbon dioxide-dominated atmosphere, which would have provided the planet with a relatively warm insulator, allowing the planet to support liquid surface water. The loss would have led to the cold, arid, and barren world the Red Planet is today. The shift is estimated to have taken place between about 4.2 to 3.7 billion years ago, just about the time scientists believe life was emerging on Earth (a theory that may have been given further credence by the recent unconfirmed discovery of bacteria fossils in Canada that have been dated at 3.8 billion years, and which lend hope for finding life on Mars, suggested the discoverers).

Mars and its thin atmosphere
Mars has a vestigial atmosphere which was believed once to be thick enough to provide the greenhouse effect needed to sustain bodies of water. [Image by HelenFIeld/Shutterstock]

MAVEN was launched in November 2013, and entered Mars orbit in September 2014. It has a ten-year mission, where it will study Mars’ upper atmosphere, ionosphere, and the planet’s interactions with the sun and solar wind. As it runs out of fuel, the orbiter will enter a decaying orbit and eventual crash onto Mars itself. Oddly enough, Phobos is also in a decaying orbit and is estimated to break up and form a planetary ring or slam into the Red Planet in roughly 30 to 50 million years.

[Featured Image by Stanislaw Tokarski/Shutterstock]