Rover Captures Sunset, Eclipse on Mars

The Opportunity rover’s latest accomplishments? Cinematographer. Two new movies created by images taken by the long-lasting rover show a blue-tinted Martian sunset, while another clip shows the Mars’ moon Phobos passing in front of the sun. “These visualizations of an alien sunset show what it must have looked like for Opportunity, in a way we rarely get to see, with motion,” said rover science team member Mark Lemmon of Texas A&M University. Dust particles make the Martian sky appear reddish and create a bluish glow around the sun.

These holiday treats from the rover’s panoramic camera lets the rest of us feel like we are — almost — there on Mars, standing beside the rover.

Lemmon worked with Pancam Lead Scientist Jim Bell, of Cornell University to plot the shots and make the moving-picture simulation from images taken several seconds apart in both sequences.

The sunset movie, combining exposures taken Nov. 4 and Nov. 5, 2010, through different camera filters, accelerates about 17 minutes of sunset into a 30-second simulation. One of the filters is specifically used to look at the sun. Two other filters used for these shots provide color information. The rover team has taken Pancam images of sunsets on several previous occasions, gaining scientifically valuable information about the variability of dust in the lower atmosphere. The new clip is the longest sunset movie from Mars ever produced, taking advantage of adequate solar energy currently available to Opportunity.

At the American Geophysical Union conference last week, MER project manager John Callas said Oppy is producing 600 watt-hours per day, and that the slight dust covering the solar arrays put the energy output at 60% of full power. Not too bad for the almost-7-year-old solar arrays, which have been repeatedly cleaned off by wind gusts.

The two Martian moons are too small to fully cover the face of the sun, as seen from the surface of Mars, so these events — called transits or partial eclipses — look quite different from a solar eclipse seen on Earth. Bell and Lemmon chose a transit by Phobos shortly before the Mars sunset on Nov. 9, 2010, for a set of Pancam exposures taken four seconds apart and combined into the new, 30-second, eclipse movie. Scientifically, images years apart that show Phobos’ exact position relative to the sun at an exact moment in time aid studies of slight changes in the moon’s orbit. This, in turn, adds information about the interior of Mars.

The movies show an artistic side to those working with the images returned by the rovers.

“For nearly seven years now, we’ve been using the cameras on Spirit and Opportunity to help us experience Mars as if we were there, viewing these spectacular vistas for ourselves,” Bell said. “Whether it’s seeing glorious sunsets and eclipses like these, or the many different and lovely sandy and rocky landscapes that we’ve driven through over the years, we are all truly exploring Mars through the lenses of our hardy robotic emissaries.

“It reminds me of a favorite quote from French author Marcel Proust: ‘The real voyage of discovery consists not in seeking new landscapes, but in having new eyes,'” he added.