Seconds after landing Sunday night, Curiosity took a handful of fuzzy black-and-white photographs.
One, taken with a device on its rear known as a Hazcam, captured the pebble-strewn ground beneath the rover, one of its wheels -- and a faint but distinctive blotch on the horizon.
Two hours Curiosity sent home a new batch of higher-resolution photos -- minus the blotch, the Los Angeles Times reported Wednesday.
That led to widespread speculation Curiosity may have captured the crash landing of the so-called sky crane that delivered the rover to the surface and then plummeted to the martian surface a safe distance away as planned.
While the blotch did look like a billowing plume of some sort erupting from the martian horizon, capturing the crash "would be an insane coincidence," one engineer at NASA's Jet Propulsion Laboratory in Pasadena, Calif., said.
JPL engineers subsequently received a new image of the landing zone, taken by another satellite, that showed Curiosity, pieces of the spacecraft jettisoned on the way to landing, and 2,000 yards away the wreckage of the "sky crane" -- in the direction Curiosity's Hazcam was facing when it took its first photos.
The new photo also showed the crashing sky crane threw up a violent wave of dirt that marked the surface of Mars.
So the "insane coincidence" may have happened after all, JPL scientists said.
"I don't think you can rule it out," Curiosity mission manager Michael Watkins said Tuesday. "It bears looking into."