Mars Express, a spacecraft by the European Space Agency, will make its closest flyby to Mars moon Phobos. The spacecraft is estimated to come as close as 45 km from the moon’s surface.
Although the flyby will be very swift, making it impossible for the Mars Express to take any pictures, this will yield some information that can shed light on the moon’s gravitational field and internal structure. This phenomenon is also expected to produce data on the solar wind patterns on the planet’s surface. Previous flybys, including the closest at 67 km in March 2010, gave the experts data from which they presumed that Phobos is made up of large blocks with huge spaces in between them. Mars Express’ closest flyby is expected to happen on December 29.
Experts have long been studying the origin of Phobos and Mars’ another moon, Deimos, which orbits the planet three times farther than Phobos. Theories about the moon’s origins are they could be asteroids captured by Mars’ gravitational force or they are debris made by a large impact on Mars.
"At just 45 km from the surface, our spacecraft is passing almost within touching distance of Phobos," Mars Express Operations Manager Michel Denis, said in a press release.
Aside from the European Space Agency, ground controls from all over the world will be monitoring Mars Express position as it nears the red planet’s moon. For 35 hours, all space agencies is expected to track the position of the spacecraft as it goes near the moon, makes the flyby, and go on its course.
According to experts, the position of Mars Express and Phobos has to be in a high precision to be able to derive the most accurate data and calculations on the internal structure of the moon.
