Japan’s Historic Mars Mission: Spacecraft Heads to Phobos to Bring Back Samples, Could Unlock Secrets of the Red Planet
Japan has launched an ambitious mission to explore Phobos, one of Mars’ two moons, and bring samples back to Earth for scientific analysis. The mission could offer crucial clues about how the Martian moons formed and provide new insights into the history of the Red Planet.
Japan has embarked on a landmark space exploration mission that could change scientists’ understanding of Mars and its mysterious moons. The country’s space agency is leading the Mars Moons Exploration (MMX) mission, which aims to collect material from Phobos and return it to Earth for detailed laboratory analysis.
If successful, MMX will mark the first time scientists have brought samples back from either Mars or one of its moons. Unlike observations made by orbiters and landers, laboratory analysis of material collected directly from Phobos could reveal details that are difficult to establish through remote sensing alone.
The mission is designed to investigate a longstanding scientific question: how did Mars’ two small moons, Phobos and Deimos, form? Scientists have debated whether the moons are captured asteroids or formed from material thrown into orbit around Mars following a major impact.
A journey to Mars and its mysterious moons
The MMX spacecraft is scheduled to reach the Martian system in August 2027. It will study Deimos before concentrating on Phobos, the larger and closer of Mars’ two moons.
The mission plans to deploy a small rover to examine Phobos’ rugged surface and help researchers understand its terrain. The spacecraft will then attempt to collect surface material, with the sample-gathering operation requiring precise navigation and careful control in the moon’s weak gravitational environment.
The collected material will be stored in a return capsule and transported back to Earth. The capsule is scheduled to land in Australia’s Woomera region in 2031, where scientists will recover the samples for analysis.
Why just 10 grams could make a difference
The mission aims to return approximately 10 grams of material from Phobos. Although the quantity may appear small, researchers believe it could support a wide range of scientific investigations.
Laboratory instruments can examine individual grains to study their chemical composition, mineral structure and possible origins. These findings could help determine whether Phobos formed from material originating on Mars or is a captured object from elsewhere in the Solar System.
Researchers will also be able to compare the returned material with meteorites, Martian observations and samples collected from other celestial bodies. Such comparisons could help scientists reconstruct the early history of Mars and the processes that shaped its moons.
The mission is therefore not simply about bringing back a piece of another world. It is an attempt to answer fundamental questions about how planetary systems develop and evolve.
A challenging mission with global scientific significance
Collecting samples from Phobos presents considerable technical challenges. Its low gravity, irregular shape and uncertain surface properties make landing and sampling operations particularly demanding.
The mission will combine remote observations, rover-based exploration and sample-return technology. Each stage is intended to provide complementary information about the moon and improve the scientific value of the material brought back to Earth.
The samples could also help researchers better understand the relationship between Mars and its moons, potentially offering new perspectives on the planet’s geological history and the evolution of the inner Solar System.
For planetary scientists, the mission represents a rare opportunity to investigate a world that has remained difficult to study directly.
India’s Mars exploration milestone: Mangalyaan
India has also made its mark in interplanetary exploration through the Mars Orbiter Mission (MOM), popularly known as Mangalyaan. Launched by the Indian Space Research Organisation (ISRO) on November 5, 2013, aboard the PSLV-C25 rocket, the mission entered Mars orbit on September 24, 2014.
Mangalyaan was India’s first interplanetary mission and established the country as the first to reach Mars orbit on its maiden attempt. It also made India the first Asian nation to achieve this milestone. The spacecraft was designed to operate for six months but continued functioning for more than eight years, providing valuable scientific data on Mars’ surface features and atmosphere. ISRO declared the mission’s operational phase over in 2022 after communication with the spacecraft was lost.
The mission carried five scientific instruments, including the Mars Colour Camera and the Methane Sensor for Mars. Its achievements demonstrated India’s ability to develop and operate cost-effective spacecraft for complex deep-space missions.
Chandrayaan-4: India’s upcoming lunar sample-return mission
India’s next major step in lunar exploration is Chandrayaan-4, an ambitious mission designed to collect lunar soil and subsurface material and bring it safely back to Earth. The Union Cabinet approved the mission in September 2024, and ISRO has identified the Moon’s southern polar region as its target area. The mission is planned for 2027, although the operational schedule remains subject to updates.
The mission aims to return approximately 2–3 kilograms of lunar samples for detailed laboratory examination. Unlike earlier Chandrayaan missions, which focused on orbital observations, landing and in-situ exploration, Chandrayaan-4 will demonstrate the complete process of collecting samples, launching from the lunar surface, transferring the samples between spacecraft modules and returning them to Earth.
The mission will involve two launches, followed by rendezvous and docking operations in Earth orbit. Its landing and sampling operations are expected to take place in the lunar south polar region, where scientists hope to investigate the Moon’s geological history and examine material from a region that remains comparatively unexplored.
India’s lunar exploration journey: From Chandrayaan-1 to Chandrayaan-5
India’s lunar programme has progressed through a series of increasingly complex missions. Chandrayaan-1 (2008): India’s first lunar mission helped advance understanding of the Moon’s mineral composition and contributed to evidence of water molecules on the lunar surface. Chandrayaan-2 (2019): The mission successfully deployed an orbiter, but its Vikram lander crashed during the attempted landing. The orbiter continued scientific observations. Chandrayaan-3 (2023): On August 23, 2023, India achieved a successful soft landing near the Moon’s south polar region, becoming the fourth country to land on the Moon and the first to achieve a landing in that region. Chandrayaan-4 (planned for 2027): The upcoming sample-return mission aims to bring lunar material back to Earth for laboratory analysis. Chandrayaan-5/LUPEX: A planned joint mission between ISRO and Japan’s space agency, JAXA, will investigate lunar resources, including water and other volatile substances, near the Moon’s south polar region.
A new era of sample-return missions
Japan’s MMX mission and India’s Chandrayaan-4 reflect a broader shift in space exploration: moving beyond observing distant worlds towards physically retrieving material from them for detailed analysis.
While MMX will investigate the origins of Mars’ moons, Chandrayaan-4 will focus on the Moon’s composition and geological evolution. Both missions will rely on advanced navigation, robotic sampling, spacecraft docking and safe-return technologies.
Their findings could strengthen scientists’ understanding of how planets and moons formed, how their surfaces evolved and how material moved through the early Solar System. For India, Chandrayaan-4 will also build technological capabilities that could support future human spaceflight and more ambitious planetary exploration.
Together, these missions represent an important step towards answering fundamental questions about our cosmic neighbourhood—not just by looking at other worlds, but by bringing pieces of them home.
