A Japanese space mission is about to launch towards Mars. But it will not land on the planet itself. Instead, the Martian Moons Exploration (MMX) mission will focus on Phobos, the bigger of Mars’s two small moons.

The mission will lift off on Monday October 19 at 20:41 BST on an H3 rocket from the Tanegashima Space Center, in the south of Japan.

This will start a five-year mission, during which the spacecraft will orbit and explore Phobos, deploy a lander, touch down and collect soil and small pebbles. In a world first, these samples will be delivered to Earth for study in laboratories.

MMX is led by the Japanese Aerospace Exploration Agency (Jaxa), in collaboration with the US, France, Germany and the European Space Agency (Esa). The overall science objective is to unravel the origins of the two Martian moons, the smaller of which is called Deimos. Mission scientists also want to examine the wider evolution of Mars and its local environment in space.

We still have no clear understanding of how the red planet got its moons. These natural satellites could have been hapless asteroids that were passing by Mars when they got captured by its gravity.

Another possibility is that that they formed when an asteroid collided with Mars, causing rocky material to be thrown out into space. Gradually, this material coalesced into Phobos and Deimos. The MMX mission will give us Phobos’s chemical composition, which could help distinguish between theories.

Grabbing samples from Phobos will be no easy task, however. Russia tried this in 2011 with its Phobos Grunt mission. The spacecraft launched successfully to low Earth orbit, but failed to fire its engines to send it toward Mars.

However, Jaxa is well placed to succeed. The space agency has already proved that it can return samples from asteroids with its Hayabusa space missions, which lasted from 2003-10 (Hayabusa) and 2018-20 (Hayabusa 2).

MMX will trial sophisticated sampling techniques designed for Phobos’s low gravity. The moon has about 0.1% the gravitational pull that Earth does. This means that a human on Phobos could jump a distance of 1.5 km horizontally without much effort.

The mission will also be a test of communication between the spacecraft and a newly developed ground station. After launch and deployment, MMX will take a year to reach Mars, arriving in August 2027. It will first circle the red planet before slipping into orbit around Phobos about a month later.

The spacecraft consists of three modules with distinct functions: a propulsion module to get MMX into orbit around Mars, an exploration module with landing and sample collection gear and a return module to deliver the sample to Earth.

The mission will make use of 13 science instruments to explore Phobos. High resolution cameras called Tengoo and Orochi will map the surface and a laser altimeter (Lidar) will build up a picture of the moon’s contours. Lidar uses laser pulses to measure the distance from the spacecraft to features on the surface.

An infrared spectrograph called MIRS will survey Phobos’s minerals, while a gamma ray and neutron detector, called Megane, will determine the moon’s elemental composition. From a greater distance, MMX will also gather data on Mars’s smaller moon Deimos.

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Read more: How did Mars get its moons? Japan’s MMX space mission aims to solve the puzzle

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The instruments will send back data that controllers will use to decide where and how to land the spacecraft on Phobos.

In early 2029, the MMX exploration module will deploy a small microwave oven-sized rover called Idefix, which has been developed jointly by Jaxa, the French space agency Cnes and the German Aerospace Center (DLR). Idefix will drop down onto Phobos’ surface from between 40 and 100m in altitude.

The rover will then right itself and travel over the surface during an operational period expected to last about 100 days. It will be using several sensors, including a Raman spectrometer and radiometer, to make a final call about where the exploration module should land.

In 2030, the module will swoop down and land on Phobos, remaining on its surface for about 2.5 hours. It will be able to extract samples from the surface once or possibly twice by landing again at a different location. The ability to sample from more than one place on Phobos is vital to understanding the moon’s composition.

The exploration module will use either an instrument called the C-sampler to drill a core or a device knowns as the P-sampler, which blows a jet of nitrogen gas to blast soil and loose pebbles off the surface and into a sample collection chamber.

The C-sampler would be able to collect a core from up to 2cm below the surface. This would provide the mission with a sample composition unaltered by solar radiation, which causes chemical changes to planetary surfaces over time. The P-sampler is a back-up option, but carries some small risk of toppling the spacecraft in low gravitational fields like the one on Phobos.

Having gathered at least 10 grams of material, the spacecraft will leave the Martian moon, separating from its landing gear. It will then travel back to Earth, arriving in 2031. On its approach, the spacecraft will eject its sample probe, which will then descend through Earth’s atmosphere. It will land using parachutes in Australia, where it will be recovered and transported to Japan.

A potential side-benefit of the mission is that samples from Phobos might also include material from Mars. Phobos closely orbits the red planet and is thought to be constantly hoovering up Martian soil. This soil is thought to be regularly ejected from the planet’s surface by asteroid impacts.

MMX could therefore be considered a lite-version of the Mars Sample Return (MSR) mission. MSR, a collaboration between the US and European space agencies, would have sent rock samples from the Martian surface to Earth. However, budgetary pressures led to the programme being effectively cancelled by US Congress.

If scientists get lucky with the samples from MMX, they might get a nice consolation prize.

Daniel Brown does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

Nasa has named the crew of its next Artemis mission, which it promised would be an “extraordinary demonstration of what is possible”. Artemis is the ambitious American-led effort to return humans to the lunar surface by 2028.

However, the Artemis III mission will not travel to the Moon. Instead, the Orion spacecraft will stay in low Earth orbit and aim to dock with lunar landing vehicles launched separately by one or two space companies.

Nasa astronauts Randy Bresnik, Frank Rubio and Andre Douglas and Italian European Space Agency astronaut Luca Parmitano will carry out the mission in late 2027.

There are two potential landers that could fly on their separate mission to then rendezvous with the Orion spacecraft; one made by Elon Musk’s SpaceX and the other by Jeff Bezos’ firm Blue Origin. They will carry astronauts down to the Moon’s surface on subsequent missions.

However, the timetable for Artemis III and the first mission to return astronauts to the lunar surface (Artemis IV) has been thrown into doubt by the recent explosion of a New Glenn rocket. This rocket is intended to launch Blue Origin’s lander, called Blue Moon.

The blast could add significant delay to the Artemis schedule and there is speculation that it could even put the US out of contention to reach the Moon before China, which is planning its own Moon landing mission for 2030.

On May 28, 2026, Blue Origin’s New Glenn rocket, which is able to carry heavy payloads, was undergoing a standard engine fire test. For reasons which are still unclear, a huge explosion destroyed the rocket and damaged Blue Origin’s only launchpad, located at Cape Canaveral Air Force Station in Florida.

To reduce costs, Nasa’s Artemis programme relies on companies like Blue Origin to deliver key elements for lunar missions, like the landers.

Rockets capable of lifting heavy payloads into orbit will be needed for launching the building blocks of Nasa’s Moon base, which will be assembled over the next few years.

Under previous plans, SpaceX’s Starship vehicle would have been used as the lander for the first two Artemis missions to touch down on the Moon. However, Starship ran into problems during flight tests, so Nasa hatched a plan B.

This backup plan brought Blue Origin’s Blue Moon lander into the mix for Artemis IV, the first mission back to the lunar surface. Now, with the explosion, even their Plan B seems to have moved out of reach.

How bad is the situation though? Blue Origin only has one launch pad that, at the moment, cannot be used. But recent updates by the company’s CEO, Dave Limp, indicated that the situation may not be as dire as it might have been. He indicated that New Glenn might even return to launch before the end of the year.

The propellant farm (which stores the rocket fuel and oxidiser that are pumped into the rocket just before launch), as well as the water tower were undamaged. So were the booster and upper stages of another New Glenn rocket held in the pad’s integration facility. The launch tower will only need to be repaired and not rebuilt.

To gain some insight into the potential impact on the timescale for a next launch, we might be able to look at a similar situation faced by SpaceX in September 2016 where a Falcon 9 rocket exploded on one of their launchpads.

They were able to continue only four months after, but from one of their alternative launch sites, none of which were fully operational at that time. But Blue Origin has no alternative site at all. SpaceX needed more than a year to start up operations again on their damaged launch site.

Kiko Dontcev, vice president of launch at SpaceX, commented on the task ahead for Blue Origin. He described the rebuild as a high precision dissection of the damaged site to help better understand the incident. “In the initial days and weeks after you’re using a scalpel not a bulldozer,” he commented on X.

This might cast doubt on hopes that New Glenn could launch again this year. Indeed, Nasa’s chief Jared Isaacman told CNBC that the launch pad might not be restored until 2028. Currently, we just do not have the full picture of the damage and work needed. So, we can only hope that New Glenn launches can resume as soon as possible.

Nasa is already trying to limit the impact of the New Glenn explosion by urging Blue Origin to look at other rockets for launching its Blue Moon lunar landers. This would allow Nasa to still meet its deadline of landing astronauts on the Moon in 2028.

But New Glenn is still needed to land hardware such as the lunar terrain vehicles for Artemis missions and a robot rover called Viper, which will scout for water ice at the Moon’s south pole.

Exploring with pride

However, with 2030 approaching fast, the knock-on effects of the explosion could lead to China beating the US to the Moon. But the Artemis programme had already been hit by delays as a result of Nasa’s dependence on government whims and variable funding. Overall, the Artemis programme has had a relatively tight budget to work with.

Space agencies like Nasa must try (as much as possible) to decouple their efforts in space from ongoing turmoil in domestic politics. It could also do well to rely less on ventures led by billionaires, who often have their own private objectives.

One could view the Chinese lunar programme as being more stable, because of their one-party state as well as their strong sense of national pride. However, there is also a lack of transparency in their space programme and a focus on propaganda.

As an outside observer, it appears that Nasa’s current timeline for landing on the Moon and establishing a permanent lunar base is slipping away. But this may not be the disaster some in the space industry think it is. Perhaps we should embrace a pride in exploring space as a community of nations working together.

Daniel Brown does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.