Japan's H3 rocket launches MMX probe to bring back a sample from Mars moon Phobos
In short
JAXA launched the Martian Moons eXploration probe MMX on H3 flight 10 from Tanegashima Space Center at 4:41 a.m. on 20 October. Outlets reported that the probe separated about 1 hour 11 minutes after liftoff and was put on a course toward Mars. It aims to return a sample from the moon Phobos in 2031, which would be a world first for the Mars region.
Read the full story 2 min read
The Japan Aerospace Exploration Agency (JAXA) launched the H3 rocket's tenth flight at 4:41:03 a.m. Japan time on 20 October from Tanegashima Space Center in Kagoshima Prefecture. The rocket carried the Martian Moons eXploration probe, MMX. Asahi Shimbun reported that the rocket accelerated to about 11.2 km per second to leave Earth's gravity and that the probe separated about 1 hour 11 minutes after launch. Mainichi Shimbun said the probe was put on a trajectory toward Mars, and Jiji Press reported it was placed in the planned orbit. [ 1 , 21 , 34 , 36 ]
The rocket was in the H3-24L form, with two LE-9 main engines and four SRB-3 solid boosters, which TBS described as the most powerful H3 configuration. TBS said it was the first time the H3 had used the long fairing. According to JAXA as cited by TBS, it is the first time the H3 has carried a planetary exploration mission. Yomiuri Shimbun, citing JAXA, said the second-stage burn after the second ignition was lengthened compared with earlier flights. [ 1 , 8 ]
MMX is meant to collect sand and rock from Phobos, one of Mars's two moons, and bring it to Earth. Outlets said that would be a world first for the Mars region. According to the plans reported, the probe reaches Mars orbit around August next year, studies Phobos and Deimos, and drops a rover developed by France and Germany on Phobos. It then lands twice on Phobos, with a target of at least 10 grams of sample. Mainichi gave around 2029 for the landings. Jiji Press said the probe would stay on the surface about two and a half hours and drive a tube-like device into the ground. The probe is to leave the Mars region in 2030 and drop the sample capsule to Earth in 2031; Jiji Press and Sankei Shimbun said it would be recovered in Australia. [ 1 , 2 , 5 , 6 , 34 ]
Mainichi Shimbun said the total development cost was 55.3 billion yen and that Mitsubishi Electric built the probe. It is 5.3 meters tall, 9 meters wide and weighs 4,480 kg, with three modules for the outbound trip, exploration and return. It carries 13 instruments, four supplied from abroad. According to Mainichi, NASA and the European Space Agency provided a spectrometer and communications equipment. Tokyo Shimbun, citing Kyodo, said NASA, ESA, the German Aerospace Center (DLR) and France's CNES take part. [ 6 , 34 ]
Asahi Shimbun said the sample is to be examined to learn whether Phobos is an asteroid captured by Mars's gravity or was formed from debris of an impact on Mars. JAXA project manager Yasuhiro Kawakatsu told a news conference on 18 October that preparations were complete. In Kyodo's report he also said the launch is not the goal but the start. Mainichi noted that China plans to launch around 2028 and aims for a sample return from Mars itself around 2031. [ 5 , 6 , 21 , 34 ]
Why it matters
Outlets describe the mission as an attempt at the first sample return from the Mars region, with the probe due to reach Mars next year. It is also the first time the H3 rocket has carried a planetary exploration mission.
Key facts
- H3 flight 10 lifted off from Tanegashima Space Center in Kagoshima Prefecture at 4:41:03 a.m. Japan time on 20 October, carrying the MMX probe. [ 1 , 21 , 31 ]
- The probe separated from the rocket about 1 hour 11 minutes after launch; Jiji Press and Sankei Shimbun reported it was placed in the planned orbit. [ 21 , 27 , 36 , 40 ]
- It is the first time the H3 rocket has carried a planetary exploration mission. [ 1 , 4 , 8 ]
- MMX is to reach Mars orbit around August next year, land twice on Phobos, and send a sample capsule to Earth in 2031. [ 5 , 6 , 34 ]
- Mainichi Shimbun gave the probe's development cost as 55.3 billion yen, built by Mitsubishi Electric, with a total weight of 4,480 kg. [ 34 ]
- The mission aims to collect at least 10 grams of sample from Phobos. [ 1 , 34 ]
Confirmed by several sources
- The H3 rocket's tenth flight, carrying MMX, launched from Tanegashima Space Center at 4:41 a.m. on 20 October. [ 1 , 21 , 27 , 31 ]
- The probe separated from the rocket about 1 hour 11 minutes after launch and was put on a course toward Mars. [ 21 , 27 , 34 , 36 , 40 ]
- The launch was the H3's first planetary exploration mission. [ 1 , 4 , 8 ]
- If it succeeds, bringing back a sample from the Mars region would be a world first. [ 1 , 2 , 6 , 8 , 34 ]
- The plan has MMX arriving in the Mars region around August next year and returning a sample capsule to Earth in 2031. [ 5 , 6 , 24 , 34 ]
- A rover developed by France and Germany is to be dropped on Phobos before the probe makes two landings. [ 2 , 5 , 6 , 34 ]
Still unclear
- Exact timing of the return to Earth Tokyo Shimbun (Kyodo) gave July 2031, while Mainichi Shimbun and Nippon TV gave fiscal 2031; other outlets said 2031.
- Size of Phobos Asahi Shimbun and Jiji Press gave a diameter of about 20 to 30 km, while Mainichi Shimbun gave 23 km.
- Whether the sample will contain material from Mars itself Asahi Shimbun said material that flew off Mars after meteorite impacts is thought to lie on Phobos, and that if the sample contains it, this could be another world first.
- Whether the landings and sample collection will succeed Mainichi Shimbun said the landings are planned for around 2029; the outlets describe the sample collection as a goal.
What local media are saying
Timeline, local time
- On 19 October the H3 flight 10 rocket was moved to the launch point at Tanegashima. [ 13 , 14 , 15 , 16 , 26 ]
- On 20 October H3 flight 10 lifted off with MMX. [ 1 , 21 , 31 ]
- Sankei Shimbun gave 05:52 as the separation time; Asahi Shimbun reported separation about 1 hour 11 minutes after liftoff. [ 21 , 30 ]
- Nippon TV reported the launch of H3 flight 10 as a success. [ 37 ]