We don’t know whether alien life ever existed on Mars.
But we know there’s some pretty strange stuff on the Red Planet regardless of whether extraterrestrial organisms ever lived there.
Now Nasa has spotted a gigantic and very unusual natural formation resembling a ‘dandelion clock’.
For those whose childhood was spent in front of a screen, a dandelion is said to turn into a ‘clock’ hwne it produces lots of downy seeds.
Kids used to claim they could tell the time by blowing away these feather-light hairs, but now they use smartphones and Apple Watches for this purpose instead.
The crater is interesting because it shows the interface between two different sorts of Martian terrain.
Nasa wrote: ‘This observation was originally intended to image the “contact” between two terrain types: a rocky ridge separates the rugged left from the smoother right side.
‘But during planning, a targeting specialist chose to extend the image further north (to the top), to capture a nearby crater.
‘That extension has given us a bonus beauty! The steep walls of the crater are covered with slope streaks formed by material falling down towards the crater’s centre.
‘There are so many in this case that the crater is reminiscent of a delicate dandelion clock. Looking closer, we can also see that the exposed layering gives us more information about the subsurface of Mars.’
A Nasa exploration robot recently picked up strange pulses in the magnetic field of Mars.
The Insight lander touched down on the Martian surface last year on a mission to look for ‘Marsquakes’ and analyse the Red Planet’s interior structure.
Insight’s instruments include a seismometer and a probe to monitor the flow of heat beneath the surface of the planet.
But it is also the first Mars probe capable of examining changes in the planet’s magnetic field.
It discovered strange ‘pulsation trains’ which erupt in the dead of the Martian night.
In a new paper analysing the data gathered by Insight, a team of scientists wrote: ‘During nighttime conditions near midnight local time, long pulsation trains are occasionally detected in the magnetic field.
‘These can last as long as two hours and have wave periods of longer than one minute.
‘These waves are strongest in the north direction and weakest vertically.
‘These measurements have important implications for future Mars exploration.’
The pulsation trains on Mars are large invisible waves detected in its weak magnetic field.
Earth has a strong magnetic field believed to be generated by liquid metal in its core, but Mars’ own field is nowhere near as strong.
Our planet’s field protects us from the ‘solar wind’ – a stream of dangerous charged particles which gushes from the sun’s superheated surface.
It’s hoped the Martian pulses will allow scientists to work out what’s going on deep beneath the surface of Mars.
Scientists think Mars once had a magnetic field like Earth’s, but this disappeared when the ‘dynamo’ deep beneath its surface was ‘turned off’.
This happened about 500 million years ago and allowed the solar wind to strip away the Martian atmosphere, causing its water to disappear and rendering it uninhabitable for life.