Astronomy News
The Challenges of Mars Missions
This coming October 20, 2026, Japan’s Martian Moons eXploration (MMX) mission is set to carry forward one of planetary science’s most ambitious goals: exploring Phobos and bringing a sample of the Martian moon back to Earth. But this pursuit did not begin with MMX. There were predecessors who tried to take up on this challenge, laying important groundwork through their own attempts to investigate Phobos.
Cr: JAXA
Reaching Mars and its moons is easier said than done. A spacecraft must navigate millions of kilometers through space and perform precise maneuvers to enter the orbit while trying to withstand high levels of radiation. The Red Planet’s thin atmosphere makes landing a spacecraft with just a parachute alone too difficult. But it is still thick enough to generate intense heating during entry. The final descent is usually referred to as the “Seven Minutes of Terror.” This is due to the fact that radio signals take more than 12 minutes to travel one way between Earth and Mars which means mission control cannot intervene immediately,leaving the spacecraft to figure things out autonomously.
The history of Mars exploration includes several examples of how small errors can lead to major setbacks. NASA’s Mars Climate Orbiter was lost in 1999 after a navigation error involving a mismatch between imperial and metric units. The Mars Polar Lander and its Deep Space 2 probes were also lost in 1999. Europe’s Beagle 2 lander failed to establish communication after reaching Mars in 2003, while the Schiaparelli lander crashed during its descent in 2016. Each mission illustrates the technical and operational challenges involved in reaching another planet.
In July 1988, the Soviet Union launched two spacecraft, Phobos 1 and Phobos 2, as part of the Phobos program. The missions were designed to study Mars and its moons, with international cooperation involving several European countries and support from NASA’s Deep Space Network, which helped track the spacecraft.
Phobos 1 lost its mission in late August 1988 while on its way to Mars. An incorrect command caused critical systems to stop functioning. Phobos 2, however, reached Mars orbit in January 1989 and returned observations of the Sun, interplanetary matter, Mars’s surface and atmosphere, and Phobos itself. The spacecraft sent back 37 images of Phobos, with a best resolution of about 40 metres.
The mission ended in March 1989, just before Phobos 2 was due to approach the moon closely and deploy two landers. Contact with the spacecraft was lost. The failure was attributed to a computer malfunction that led to a loss of attitude control and, ultimately, power. Although the program did not complete its planned lander operations, the observations gathered by Phobos 2 contributed to scientific knowledge of Mars and its moon.
Russia later attempted to return to Phobos exploration with Phobos-Grunt. Launched in November 2011, the spacecraft was intended to collect approximately 200 grams of material from Phobos and return it to Earth. It also carried Yinghuo-1, a small Chinese Mars orbiter. However, the engine burn needed to leave low Earth orbit failed, leaving the spacecraft stranded around Earth. Recovery attempts were unsuccessful, and Phobos-Grunt re-entered Earth’s atmosphere in January 2012 over the Pacific Ocean.
Japan has also faced setbacks in its efforts to explore Mars. Jaxa’s Nozomi spacecraft, which was launched in 1998 to study the Martian atmosphere, experienced technical problems such as propellant loss and complications associated with a solar storm. Although Nozomi, whose name means “hope” in Japanese, never entered orbit around Mars as planned, it continued its journey around the Sun instead. There might be setbacks but it does not mark the end of progress. JAXA’s Hayabusa mission encountered numerous technical difficulties on its journey to reach the asteroid Itokawa, but it successfully returned samples back to Earth in 2010. This success helped pave the way to develop Hayabusa2 which successfully returned samples from the asteroid Ryugu in 2020.
These missions show how challenging it can be to conduct space explorations. Despite setbacks, these represent important chapters in the history of planetary exploration and how lessons gained from difficult missions can support improvements in designing upcoming spacecrafts and planning operations in the continuing effort to understand these small, enigmatic worlds. JAXA’s MMX mission is preparing to take the next step, it builds on this legacy, bringing renewed hope that humanity can finally study a sample of Phobos directly on Earth.
With just two days to go before the anticipated launch of MMX, join NARIT and ITCA as we continue to uncover the science and history behind this much awaited mission to explore the Martian moons!