A rocket is set to blast off towards one of Mars's moons tonight in an ambitious £262million mission.
The Japanese spacecraft, known as Martian Moons Exploration (MMX), will this evening begin its 300million-mile mission to Phobos - the larger of the Red Planet’s two satellites.
Its aim is to collect at least 10g of dust and rock from the moon's surface, before heading back to Earth.
The mission is expected to return the first-ever samples collected from the vicinity of Mars, with tiny grains of material believed to contain a wealth of scientific information.
Experts hope the samples will finally settle a decades-old debate over whether Phobos is an asteroid that was 'captured' by Mars's orbit, or the remains of a giant collision involving the Red Planet.
'Through detailed observations and analysis of the samples obtained from Phobos, this mission seeks to clarify the formation of the Martian sphere and the Solar System, explore how life began, and pave the way for future deep-space exploration,' the Japan Aerospace Exploration Agency (JAXA) said.
Phobos, the largest of the Red Planet's two moons, is the ambitious mission's set destination
The spacecraft's aim is to touch down on Phobos and scoop up at least 10g of dust and rock from the moon’s surface before beginning the long journey back to Earth (artist impression)
MMX is set to launch on an H3 rocket at 8.41pm (BST) today, from the country's Tanegashima Space Centre.
The spacecraft consists of three components with specific functions, including a propulsion module to get MMX to Mars, an exploration module with sample collection gear and a return module to deliver the sample to Earth.
After takeoff, the rocket will spend several years travelling through deep space before orbiting Phobos.
In early 2029, a small microwave-sized rover will drop down on to the moon’s surface and spend 100 days exploring its landscape.
Its findings will inform the exact area where the exploration module should land.
Once confirmed, the spacecraft will descend to the surface of Phobos then spend two-and-a-half hours collecting material.
Scientists hope to gather samples from one or even two separate locations, giving them a better understanding of the moon's composition.
To do this, MMX will use one of two collection systems. The primary option is the C-sampler, which can drill up to 0.8 inches (2cm) beneath the surface and retrieve material that has been shielded from the sun's radiation.
A second system, known as the P-sampler, uses a burst of nitrogen gas to blast dust and small rocks into a collection chamber.
In early 2029, a small microwave-sized rover will drop down on to the moon’s surface
The spacecraft will spend two-and-a-half hours collecting samples from Phobos for research
In total, the spacecraft is equipped with 13 scientific instruments that will be used to examine Phobos in unprecedented detail.
High-resolution cameras, called Tengoo and Orochi, will photograph and map the moon's surface, while a laser altimeter will create a detailed 3D picture of its shape and terrain.
Another instrument, called MIRS, will analyse the moon's minerals, and a gamma-ray and neutron detector known as Megane will help reveal its chemical makeup.
The mission will also study Mars's smaller moon, Deimos, from afar.
After it has gathered at least 10g of material, the spacecraft will then leave the Martian system and travel back home, arriving in 2031.
As the spacecraft approaches Earth, it will release a capsule carrying the precious samples.
The capsule will plunge through the atmosphere before descending by parachute into the Australian outback, where it will be recovered and flown to Japan for analysis.
Martian Moons Exploration is to launch at 8:41pm (BST) today from a Japanese space centre
Experts hope the samples will finally settle a decades-old debate over whether Phobos is a captured asteroid or the remains of a giant collision involving the Red Planet itself
Studying material directly in laboratories on Earth will allow far more detailed analysis than is possible in space.
‘Mars is a planet that shares many similarities with Earth, yet today it has only a thin atmosphere and a cold environment,’ JAXA said.
‘To unravel the mystery of how Mars evolved into its present state, scientists would ideally study Mars itself.
‘However, the planet's strong gravity presents significant technical challenges for landing and sample return missions.
‘For this reason, MMX has selected Phobos, one of Mars's moons, as the exploration target.’
Scientists are also hoping the samples may contain tiny fragments of Mars itself.
Because Phobos orbits so close to the planet, debris blasted from the Martian surface by asteroid impacts may have become embedded in the moon over billions of years.
The European Space Agency (ESA) has provided the spacecraft’s deep space communication equipment.
‘The data and samples returned by MMX are a window to study the evolution of Mars and the Solar System,’ Elliot Sefton-Nash, ESA MMX Project Scientist, said.
‘Bringing samples to our most sophisticated labs here on Earth is a multiplier for discoveries, because our most precise instruments are too large, complex or sensitive to send to space.
‘Even after the mission has been completed, future generations of scientists will study the Phobos samples with even more advanced instruments – samples brought to Earth are the gift that keeps on giving.’