In May, the "Mars Webcam" aboard the Mars Express will be available for public imaging requests, according to the European Space Agency (ESA). There are observation slots available to the public. ESA is inviting schools, science clubs, astronomy groups and youth organizations to submit a proposal to use the webcam and to image another planet.

The webcam, or VMC, is a low-resolution camera that was intended for visuals of the Beagle lander separation, but since 2007, the webcam has provided the world with unique images of Mars - images that can't be obtained from Earth, according to ESA.

While not a scientific instrument, per say, the camera has provided quality photos of martian atmospheric activity and features like Olympus Mons and the Tharsis Montes.

"In May, Mars will be in solar conjunction, meaning that line-of-sight radio signals between Earth and Mars Express will be disrupted by the Sun," wrote ESA. "As a result, the spacecraft's professional scientific payload will be switched off. This offers a first-ever, three-day period when the VMC camera can be freely pointed at almost any target from almost any point in the 300 x 10 000 km orbit."

The campaign will take place May 25, 26 and 27. Interested groups must register by March 27, 12 CET. There will be a tutorial via an #ESAHangout in Google+ and YouTube on the VMC camera and how its images are planned and acquired on March 19. Any submitted proposals can be amended, but all proposals are final on the cut-off date, March 27.

According to ESA: "While any number of eligible groups may submit proposals, only the most promising will be selected, one slot per group, corresponding to the eight (or so) observation slots available (the number varies depending on the targets proposed).

"Proposals must include the desired observation target, a brief note about why it's interesting and a description of the intended project that will fully exploit the images. Proposals with strong educational value and representing a cohesive team effort will have the best chances of being accepted.

"In return, ESA expects that groups that are awarded a slot will use 'their' image set in a scientific or artistic project that makes full, imaginative use of the visual information they contain. The projects must be shared with us, and we'll publish these later in the VMC blog."

For more information, Tweet using the official hashtag #vmcschools or post a question in the Mars Express blog.