Martian Solar Eclipse: Passage of the Martian moon Phobos in front of the Sun.© NASA/JPL-Caltech/ASU/MSSS/SSI
Moon in front of the sun: The Mars rover Perseverance has filmed the clearest video of a Martian solar eclipse to date. During this April 2 eclipse, Mars’ small moon Phobos passed in front of the Sun as a dark blob. The rover mast camera image even shows structures on the dark moon. The details of the passage help track the orbit of Phobos and how it changes.
The Martian moon Phobos is a fragile dwarf: The irregularly shaped chunk is only a good 20 kilometers across and is marked by long cracks and impact scars. In addition, it orbits Mars dangerously low at an altitude of only 6,000 kilometers and could therefore in a few million years break apart. Planetary researchers also suspect that the small moon of Mars once emerged from the rubble of a larger one predecessor or from an early one ring of mars originated.
Phobos’ passage in front of the sun
On April 2, 2022, the Mars rover perseverance observed the Martian moon Phobos during a special event – a Martian solar eclipse. The potato-shaped moon passed directly in front of the sun. Because Phobos is 157 times smaller than our Earth’s moon, it only covered a small part of the sun’s disk – so it didn’t get dark on Mars. The eclipse also lasted only 40 seconds – but was spectacular for planetary researchers:
Thanks to a special filter, the rover’s mast camera filmed the lunar passage in high resolution and without being overshadowed by the sun. “You can see details in the shape of Phobos, like rock ridges and hills in the lunar landscape,” says Mark Lemmon of the Space Science Institute in Boulder. “And you can see sunspots. It’s just great that we’re seeing this eclipse exactly as the rover experienced it on Mars.”
Information about the orbit of the moon of Mars
Perseverance is not the first Mars rover to send images of a Phobos passage to Earth: the two rover Spirit and Opportunity delivered the first time-lapse images of such a solar eclipse in 2004, and the Curiosity rover also filmed such an event. However, Perseverance’s camera system now delivers recordings of the Phobos transit in the highest frame rate and resolution to date.
The recordings of the various passages of Phobos in front of the sun have already helped to determine the orbit of the Martian moon more precisely over the past two decades. This allows planetary researchers to study the development of Phobos’ slow approach to Mars more closely and thus better predict its fate.
Source: NASA