Nasa wants to send helicopter drones to Mars to scout out the red planet for rovers

Though gravity is much less strong on Mars, the atmosphere is far thinner

An early design for the helicopter as it would look on Mars (Nasa)

Nasa plans to send drone helicopters to Mars, so that they can fly around the planets surface and scout it out.

The helicopters, which Nasa compares with remote control toy drones, will be able to scope out areas of Mars so that scientists can use the information to decide where drones should head to.

Nasa’s Jet Propulsion Laboratory is in the early stages of development of the helicopters,

The biggest challenge for those behind the plan is making a helicopter that can take off and land safely on the planet, where the atmosphere is vastly different from that on Earth.

While helicopters might seem to be easier to fly on Mars, given the plane has three-eighths of the gravity of Earth, it is actually much harder since the atmosphere is around 100 times less dense.

Helicopter blades work using the density of the atmosphere — so one on Mars would have to spin much faster, or use bigger rotor blades.

Nasa has been testing prototype machines in a big vacuum chamber, where scientists can change the atmospheric density so that it’s like that on Mars. They have built scale models of the helicopters, which must spin at around 2400 revolutions per minute to be able to take off.

The system is designed to fly for about two or three minutes per day. The rest of the time will be spent charging the helicopter using onboard solar panels, which will keep it warm as well as providing energy for the flights.