Another great discovery is always behind another hill, but what to do if you can't see behind it? This is a problem NASA faces with Mars vehicles that travel on its surface. That's why NASA is looking for solutions in robotic helicopters that could examine the surface in advance of the vehicle moving in that direction, giving engineers on Earth data to help them better steer the vehicle.

Current vehicles on Mars have a major disadvantage in this. Curiosity and Opportunity can only be seen ahead within the limits allowed by the arms on which the cameras are located. This is quite restrictive, especially on a small planet like Mars, where the horizon is very close - already at a distance of 3,4 km. In contrast, the Earth has a visible horizon at a distance of 4,7 km. In addition, the Mars terrain is very mountainous, which creates dead spots where the cameras of the vehicles cannot see. Although NASA has probes in orbit (such as Mars Reconnaissane), it's similar to trying to find a parking space from a distance of 8 km with the help of binoculars.

One solution NASA is researching is to launch small robotic helicopters the size of a small box. Conceptual tests are currently underway. Helicopters will use cameras and other sensors to examine the vehicle's surroundings to find the safest route for it.

According to NASA, the goal is to create a helicopter specially designed for this task. The space agency says it must weigh a maximum of 1 kg, there must be two counter-rotating rotors with a diameter of 1,1 meters. It looks like a lot, but the Mars atmosphere is very sparse, so the rotors have to be bigger to develop enough buoyancy. Even with such a large diameter, they will have to rotate at 2400 speeds per minute (= 40 revolutions per second).

The robotic helicopter will be powered by a solar panel located on the rotor hub cover. The estimated flight time is 2 to 3 minutes within a distance of 500 meters from the parent vehicle. At the same time, electricity will ensure helicopter warmth during Mars chilly nights.

NASA is currently testing a prototype with an anchored flying robot in a vacuum chamber simulating conditions on Mars at the Jet Propulsion Laboratory (JPL), Pasadena, California.

When can we expect robotic helicopters on Mars? It will be possible around 2020 to 2021, when a carriage is to be placed on Mars Curiosity 2.

The following video sets out a discussion on what it will take to use a helicopter on Mars. The video is in English with English subtitles.