Japan launches MMX probe to bring back samples from Mars moon Phobos
In short
Japan's space agency JAXA launched the Mars moon probe MMX on an H3 rocket from Tanegashima Space Center at about 04:41 on 20 October. The probe separated about 1 hour 11 minutes later and entered its planned orbit toward Mars. It aims to collect sand from Phobos and return it to Earth in July 2031.
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Japan's space agency JAXA launched the Mars moon probe MMX on 20 October at about 04:41 local time. An H3 rocket, flight No. 10, carried it from Tanegashima Space Center in Kagoshima Prefecture, Japanese media cited by Newsis and Korea Economic Daily reported. Yonhap reported from Tokyo that the launch succeeded. [ 2 , 3 , 4 ]
According to Newsis, the probe separated about 1 hour 11 minutes after launch at an altitude of about 592 km and entered its planned orbit toward Mars. Korea Economic Daily said the rocket shed its four boosters and first stage in turn on the way up. [ 3 , 4 ]
MMX aims to collect sand and other samples from Phobos, one of Mars's two moons, and bring them to Earth. Newsis says it is due to reach Mars orbit around August next year and observe Phobos with its onboard cameras. Newsis says it will then land twice around early 2029 and use a robotic arm to collect samples. A rover developed by Germany and France is to be released onto Phobos first. Asia Economy gave a different schedule, saying MMX is to approach to about 40 m from the surface in late 2028 or early 2029 and release the rover, which would survey the terrain for about 100 days before MMX attempts a landing. [ 3 , 5 ]
After sampling, MMX is to fly past Deimos, the other Mars moon. It is due to leave the Mars region in November 2030 and drop the sample capsule in an Australian desert area in July 2031, the reports said. Yonhap, Korea Economic Daily and Asia Economy all say the aim is to return the samples in 2031. [ 1 , 3 , 4 , 5 ]
Yonhap and Korea Economic Daily say success would be a first sample return from the Mars region. Newsis quoted Yomiuri as saying it would be an achievement neither the United States nor China has reached. Asia Economy noted that Russia launched a probe in 2011 to bring back Phobos samples but failed, and that no probe has yet landed on Phobos. [ 1 , 3 , 4 , 5 ]
Yonhap and Newsis say JAXA and Mitsubishi Electric developed MMX at a cost of about 55.3 billion yen. The probe weighed 4,480 kg at launch, which Yonhap called the heaviest of any Japanese probe. NASA, the European Space Agency, Germany's DLR and France's CNES took part. Newsis says four of the 13 onboard instruments came from overseas agencies. Asia Economy lists a NASA spectrometer among the instruments and says NASA's support was about 87 million dollars. [ 1 , 3 , 5 ]
Korea Economic Daily said the H3, developed by JAXA and Mitsubishi Heavy Industries since 2014, failed on its first flight, then had five straight successes and failed again last December. It said the rocket has succeeded since launches resumed in June, and that the overall success rate rose from about 78% to 80% with this tenth launch. [ 4 ]
Yonhap and Korea Economic Daily describe two theories on how Phobos formed. In one, a body passing near Mars was captured by it. In the other, debris from an impact on Mars gathered into the moon. [ 1 , 4 ]
Why it matters
If MMX succeeds, it would be the first sample return from the Mars region, according to Yonhap and Korea Economic Daily. Samples are expected to help explain how Phobos formed, which Newsis says could help clarify how the solar system formed. The launch also extended the H3 rocket's run of successes after its December failure.
Key facts
- JAXA launched the Mars moon probe MMX on an H3 rocket (flight No. 10) at about 04:41 on 20 October from Tanegashima Space Center in Kagoshima Prefecture. [ 1 , 2 , 3 , 4 ]
- MMX separated about 1 hour 11 minutes after launch at an altitude of about 592 km and entered its planned orbit toward Mars, Newsis reported. [ 3 , 4 ]
- The probe is due to reach Mars orbit around August 2027, land on Phobos twice and collect sand and other samples. [ 3 , 4 ]
- MMX is due to leave the Mars region in November 2030 and drop the sample capsule in an Australian desert area in July 2031. [ 1 , 3 , 5 ]
- JAXA and Mitsubishi Electric developed MMX at a cost of about 55.3 billion yen; it weighed 4,480 kg at launch, the heaviest Japanese probe so far, according to Yonhap. [ 1 , 3 ]
- NASA, the European Space Agency, Germany's DLR and France's CNES took part in the project. [ 1 , 3 ]
Confirmed by several sources
- MMX was launched on 20 October at about 04:41 aboard an H3 rocket from Tanegashima Space Center. [ 1 , 2 , 3 , 4 ]
- The probe separated from the rocket about 1 hour 11 minutes after launch and entered its planned orbit toward Mars. [ 3 , 4 ]
- The sample capsule is planned to return to Earth in 2031, landing in Australia. [ 1 , 3 , 4 , 5 ]
- A small rover developed by Germany and France is to be released onto Phobos before MMX itself lands. [ 1 , 3 , 5 ]
Still unclear
- When MMX will land on Phobos. Newsis says two landings are planned around early 2029; Asia Economy says the probe is to come within about 40 m of the surface in late 2028 or early 2029, before the rover is released and MMX attempts a landing.
- The cost of the mission. Yonhap and Newsis give about 55.3 billion yen for development by JAXA and Mitsubishi Electric; Asia Economy says JAXA has put in about 350 million dollars so far. The documents do not say whether these figures cover the same costs.
- How Phobos formed. Yonhap and Korea Economic Daily describe two theories: capture of a passing body, or an accumulation of debris from an impact on Mars. Asia Economy says the reason for Phobos's near-circular orbit is not yet clear and that scientists do not know the state of its surface.