Moon Dirt From Mars! A Daring Mission to Mars’s Tiny Moon Launches in Days
Quick Summary
Japan’s space agency, JAXA, is about to launch the most ambitious Mars-region mission ever. A spacecraft called MMX will travel to Phobos — one of Mars’s two tiny moons — scoop up dirt, and fly all the way back to Earth. Today, NASA held a special meeting to explain its role in this exciting trip.
What Happened?
NASA scientists held a public teleconference today to talk about the Martian Moons eXploration mission, known as MMX. The spacecraft is sitting on a launchpad in Japan right now, ready to lift off on Monday, October 19. It will ride into space on a powerful rocket called the H3.
Phobos is one of the strangest objects in our solar system. It is shaped a bit like a lumpy potato. It is so small that if you stood on it, you could throw a ball fast enough to launch it into space. Phobos is only about 14 miles wide — smaller than many cities.
MMX will take about a year to reach Mars. Then it will do something no spacecraft has ever done before. It will slip into a special orbit that keeps it close to Phobos while Mars’s gravity keeps pulling on it. Over the next three years, the spacecraft will study the moon’s surface very carefully. It will land — at least once, maybe twice — and scoop up at least 10 grams of dust and rock. That is about the weight of two paper clips.
Then the spacecraft will make the long journey home. Scientists expect those tiny samples to arrive back on Earth in 2031. That is five years from now.
MMX is not going alone. It carries a small rover built by teams from France and Germany called Idefix. NASA contributed a special science tool called MEGANE that measures what the surface is made of using invisible rays.
Why Does It Matter?
Scientists are still arguing about where Phobos came from. Did a giant rock crash into Mars long ago and create Phobos, the way Earth’s Moon was made? Or did Mars’s gravity capture a wandering asteroid? The dirt samples should help answer that mystery.
The answers matter beyond just Mars. Understanding what happened in the early solar system helps us understand how planets like Earth formed — and whether life could have started in other places. This will be the first time humans have ever collected a sample from a moon that orbits another planet.
Big Words
- Phobos — one of Mars’s two small moons; its name means “fear” in ancient Greek
- Sample return — a space mission that brings a piece of another world back to Earth for scientists to study in a lab
- Orbit — the curved path one object takes as it travels around another, held in place by gravity
- Rover — a small robotic vehicle that rolls around the surface of a moon or planet to explore
- MEGANE — the NASA science instrument on MMX; it uses gamma rays and neutrons to figure out what elements make up Phobos’s surface
Fun Fact
Phobos is so close to Mars that it orbits the planet three times every single day. If you lived on Mars, you would watch Phobos rise in the west, zip across the sky, and set in the east — all in about four hours!
Think About It
If you could choose any moon or asteroid in the solar system to send a sample-return mission to, which one would you pick and what do you think scientists would find?
Sources
- ESA — Mars moon lander set to launch on 19 October
- Planetary.org — MMX, Japan’s Martian Moons eXploration mission
- SpaceWatch.Global — JAXA’s Martian Moons eXploration (MMX) Mission Set to Launch Next Tuesday on H3 Rocket
- CNES — MMX mission page (updated September 29, 2026)
- SpaceCalendar.com — NASA Media Telecon on NASA’s Role in JAXA’s MMX Mars Mission, Oct 15 2026