Mars, Earth and the Sun are all set to line up in a cosmic alignment known as an 'Opposition'. Courtesy NASA.

THERE may not be life on Mars, but PLEASE: let there be light. And there was light. But where is it coming from?

An unexplained shard of light in a photo from NASA’s Curiosity rover has got UFO enthusiasts excited, the Houston Chronicle reports (technically, it doesn’t appear to be flying so it can’t be a UFO, so there’s one theory quashed - Unless, of course, it’s refuelling).

Scott C. Waring, who runs the UFO Sightings Daily site, posted the photo on April 6.

Waring said the light shines upward, as if from the ground, and is very flat across the bottom.

“This could indicate there is intelligent life below the ground and uses light as we do,” Waring noted on his website. “This is not a glare from the sun, nor is it an artifact of the photo process.”

The strange light, spotted in a photo taken by the rover’s right-hand navigation in a new study area known as the Kimberley, does not appear in pictures from the left-hand camera, suggesting the “light” is actually a speck of lost data, reports NBC. An imaging expert at NASA’s Jet Propulsion Laboratory says the blip appears to have been caused by a cosmic ray hit.

Although the space agency hasn’t issued any statement about the phenomenon, bloggers and NASA watchers have chimed in on what is seen in the photo, which was sent over millions of kilometres of space before being picked up by the Jet Propulsion Laboratory in Pasadena, California, the Houston Chronicle says.

Four different types of rock come converge at the Kimberley.

“This is the spot on the map we’ve been headed for, on a little rise that gives us a great view for context imaging of the outcrops at the Kimberley,” the Curiosity mission’s Melissa Rice, of the California Institute of Technology in Pasadena, said.

So what do you think it is? Tell us below

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