Mars helicopter photographs Mars rover

The American space agency's Ingenuity Mars helicopter has photographed the Perseverance rover.

The one-tonne robot, which acts as the drone's radio base-station, is seen nestled in the upper-left corner of a newly released image.

The picture was acquired by Ingenuity during its third demonstration flight on Sunday.

At the time, the mini-helicopter was about 85m from the rover and flying laterally at an altitude of 5m.

Sunday's sortie was the most ambitious yet for for Ingenuity and saw it travel 100m over the course of 80 seconds.

Nasa says the drone's next two flights, to be conducted in the coming days, will be its last and will push the chopper technology very hard in terms of speed and distance travelled.

Engineers want to find the Ingenuity's limits, even if that means crashing it in the process.

The major difficulty in flying on the Red Planet is the very thin atmosphere, which has just 1% of the density here at Earth.

This gives the rotor blades on a rotorcraft very little to bite into to produce lift. There's help from the lower gravity at Mars, but still - it takes a lot of work to get up off the ground.

The Nasa chopper was therefore made extremely light and given the power to turn those blades super-fast - at over 2,500 revolutions per minute.

Ingenuity was carried to Mars by the Perseverance rover, which landed in Jezero Crater in mid-February.

As well as acting as a base station for the chopper, the six-wheeled robot has been taking stills and movies to document the demonstration flights. Soon, however, Perseverance must abandon the helicopter to begin its primary mission of searching for signs of life on the Red Planet.