Why does the Curiosity rover only have a 2MP camera, along with just 8GB flash storage? Is it some special NASA trick that pulls more info from low-res sensors? Is it something to do with the kind of space radiation that turned Reed Richards and team into the Fantastic Four? Nope – it turns out that the reason that the Mars Rover is using 8-year-old camera technology is because the camera design was specced eight years ago, way back in the swirling mists of 2004.
Not that the data pipe between here and Mars could handle much more data than a 2MP camera can produce, anyway. The UHF radio that beams back photos and other data talks to two spaceships in Mars orbit and can manage to beam back just 250 megabits per day to Earth.
The camera was designed by a team headed by Mike Ravine, at Malin Space Science Systems, and there were actually four of them. This also led to design compromises, as the mission’s cameras had different purposes but shared the same basic architecture. For instance, to capture the rover’s descent, the team wanted high-speed video. Back in 2004, this meant 2MP sensors, as 4MP sensors ran at half the speed.
The final reason for using the Kodak KAI-2020 sensor was that the team had used them before, and found them easy to work with. When your camera is – on average – 225 million kilometers away, then reliability and familiarity count for a lot more than pixel counts. Especially as Curiosity is perfectly capable of stitching together panoramas.
Source: DP Review.