The search for life on Mars has taken a giant leap with Nasa’s most sophisticated rover yet.
Perseverance successfully landed on the red planet on Thursday after a six-month journey through space.
It’s chock-full of pioneering technology, including a super-light helicopter, to help it look for ancient signs of life.
It will also investigate the possibility for people to live and work on Mars.
Here’s what you need to know about humanity’s latest efforts to expand its extra-terrestrial footprint.
Mars is seen as an ideal candidate for exploration because it is close by in our solar system and is the most similar to Earth.
One of the biggest questions is whether life has existed beyond Earth and Mars is a good place to start investigating, given that evidence points to it once being full of water, warmer and with a thicker atmosphere, making it a potentially habitable environment.
What will this rover do?
It is Nasa’s most ambitious Mars mission yet, totalling around £2.16 billion ($3 billion).
The US is dispatching a six-wheeled rover the size of a car, named Perseverance, to collect rock samples that will be brought back to Earth for analysis in about a decade.
It touched down in an ancient river delta and lake known as Jezero Crater, which has a diameter of around 30 miles.
Besides seeking signs of past microscopic Martian life, Perseverance will also release a spindly, 4lb (1.8kg) helicopter that will be the first rotorcraft ever to fly on another planet.
Its cameras will shoot colour video of the rover’s descent, providing humanity’s first look at a parachute billowing open above Mars, while microphones capture the sounds.
The rover will also attempt to produce oxygen from the carbon dioxide in the thin Martian atmosphere.
This is important because extracted oxygen could someday be used by astronauts on Mars to breathe as well as for making rocket propellant.
While prowling the surface, Perseverance will peek below, using radar to locate any underground pools of water that might exist.
Nasa wants to return astronauts to the moon by 2024 and send them from there to Mars in the 2030s.
To that end, the space agency is sending samples of spacesuit material with Perseverance to see how they stand up against the harsh Martian environment. How did it land safely?
It was difficult – only the US has ever managed to land a rover onto Mars.
Spacecraft have blown up, burned up or crash-landed, with the casualty rate over the decades exceeding 50%.
Dr. Melissa Rice, Associate Professor of Planetary Science at Western Washington University, explains why landing will be so difficult
China’s last attempt, in collaboration with Russia in 2011, ended in failure.
Perseverance made it thanks to brand-new guidance and parachute-triggering technology, which helped to steer the craft away from hazards.
Ground controllers were helpless, given the 10 minutes it takes radio transmissions to travel one-way between Earth and Mars.
Jezero Crater is worth the risks, according to scientists who chose it over 60 other potential sites.
Where there was water, and Jezero was apparently flush with it 3.5 billion years ago, there may have been life, though it was probably only simple microbial life, existing perhaps in a slimy film at the bottom of the crater.
But those microbes may have left tell-tale marks in the sediment layers and Perseverance will hunt for rocks containing such biological signatures, if they exist.
Along with Perseverance, China and the UAE have also launched missions.
The three nearly simultaneous launches are no coincidence: the timing is dictated by the opening of a one-month window in which Mars and Earth are in ideal alignment on the same side of the Sun, which minimises travel time and fuel use. Such a window opens only once every 26 months.
Who has made it to Mars?
The US is the only country to successfully land a spacecraft on Martian soil so far, having done so eight times since 1976 – its InSight and Curiosity rovers are still operational.
Eight other spacecraft are currently observing Mars from above, including three belonging to the US, two European and one apiece from India, China, and the UAE.
What of China’s latest attempt?
China’s Tianwen-1 probe successfully completed its journey to Mars’ orbit last week, in the first stage of a quest to eventually land on the red planet and search for signs of life.
It is the first time the country has successfully made the journey, after its attempt with Russia in 2011 failed to make it through Earth’s orbit.
But the hardest part of the mission will be managing to land a rover on the Martian surface, a complex feat that has so far only ever been achieved by Nasa.
China plans to attempt to send its rover down to the surface in May, where they hope to search for underground water as well as evidence of possible ancient life.
The solar-powered rover weighs 529lb (240kg) and should operate for about three months, while the Tianwen-1 orbiter is expected to last two years.
Last week Tianwen-1 – or the Quest Tor Heavenly Truth – sent back its first photo of Mars, taken 1.4 million miles away from the planet.
And what about the United Arab Emirates’ mission?
The United Arab Emirates set off to Mars seven months ago – though this is a probe, so will not take on the difficult task of landing on the planet.
Amal – or Hope – is the first interplanetary mission for the Arab world and will look at the upper atmosphere and monitor climate change for at least two years.
Entering the planet’s orbit involved a critical and tricky manoeuvre, Mars orbital insertion (MOI).
Achieving MOI saw the spacecraft rotated to position for a deceleration burn of 27 minutes and slowed down from its cruising speed of 121,000km/h to something nearer to 18,000km/h.
Isn’t Europe planning a mission?
The European Space Agency, along with the Russian Roscosmos, is hoping to send its first rover, named after English chemist Rosalind Franklin, to Mars.
Originally planned for launch last summer, the ExoMars mission has been postponed for at least two years as a number of key tests still need to be carried out.
Given that the journey from Earth to Mars can only be attempted when the planets are in specific positions, the next launch date will not be until between August and October 2022.