JAXA Archives

October 21, 2023October 21, 2023 by Matt Williams

The Solar Wind Whistles as it Passes Mercury

Image of chorus wave generation on Mercury. Credit: NASA/JHUAPL/Carnegie Institution of Washington

Mercury is the closest planet to our Sun, ranging from 46 million km (28.58 million mi) at perihelion to 69.82 million km (43.38 million mi) at aphelion. Because of its proximity, Mercury is strongly influenced by the steam of plasma constantly flowing from the Sun to the edge of the Solar System (aka. solar wind). Beginning with the Mariner 10 mission in 1974, robotic explorers have been sent to Mercury to measure how solar wind interacts with Mercury’s magnetic field to produce whistler-mode chorus waves – natural radio emissions that play a key role in electron acceleration in planetary magnetospheres.

In addition to being the cause of geomagnetic storms and auroras in planetary atmospheres, these waves also lead to electromagnetic vibrations at the same frequencies as sound, producing chirps and whistles. In a recent study, an international research team consulted data from the BepiColombo International Mercury Exploration Project, which gathered data on Mercury’s magnetosphere during its first and second flyby. Their results are the first direct probing of chorus waves in Mercury’s dawn sector, which showed evidence of possible background variations in magnetic field.

August 28, 2023August 28, 2023 by Nancy Atkinson

Crew-7 Reaches the International Space Station

The SpaceX Dragon Endurance spacecraft, with four Crew-7 crew members aboard, approaches the space station for a docking on Sunday, Aug. 27, 2023. Credit: NASA TV

SpaceX Crew-7, the next group of four astronauts, are now on board the International Space Station, and this diverse crew is definitely putting “International” in the ISS. The new crew hails from four different countries: the US, Denmark, Japan and Russia. There will be 11 people on board the station for a few days before the Crew-6 foursome head back to Earth.

NASA has at least 200 science experiments and technology demonstrations queued up for Crew-7[‘s six months space, many of which will help prepare for the upcoming Artemis missions.

June 26, 2023June 26, 2023 by Matt Williams

Germany is Building a Tiny Rover That Will Roam the Surface of Phobos

Artist's impression of the IDEFIX rover on Phobos, with the MMX spacecraft in the background. Credit: DLR

At this very moment, eleven robotic missions are operating in orbit or on the surface of Mars, more than at any point during the past sixty years. These include the many orbiters surveying the Red Planet from orbit, the handful of landers and rovers, and one helicopter (Ingenuity) studying the surface. In the coming years, many more are expected, reflecting the growing number of nations participating in the exploration process. Once there, they will join in the ongoing search for clues about the planet’s formation, evolution, and possible evidence that life once existed there.

However, there’s also the mystery concerning the origin of Phobos and Deimos, Mars’ two satellites. While scientists have long suspected that these two moons began as asteroids kicked from the Main Belt that were captured by Mars’ gravity, there is no scientific consensus on this point. This is the purpose of the Martian Moons eXploration (MMX) mission currently under development by the Japan Aerospace Exploration Agency (JAXA), which will explore both moons with the help of a Phobos rover provided by the German Aerospace Center (DLR) and the French National Center of Space Studies (CNES).

March 26, 2023March 26, 2023 by Scott Alan Johnston

Asteroid Ryugu Contains Niacin (aka Vitamin B3)

In December 2020, JAXA’s Hayabusa2 spacecraft delivered a pristine sample of otherworldly dust and rock from asteroid Ryugu to Earth. Scientists have since had the opportunity to study the sample, and announced last week that the asteroid contains organic molecules important for life. In particular, they discovered Niacin, otherwise known as vitamin B3, and Uracil, one of the four core components of ribonucleic acid (RNA).

November 17, 2022November 17, 2022 by Evan Gough

JAXA’s Ambitious Mission to Phobos Will Even Have European-Built Rover

Phobos, a moon of Mars. — Japan is sending a spacecraft to Phobos to study it and collect samples for return to Earth. A German rover will be part of the fun. Image Credit: NASA/JPL-Caltech/University of Arizona

Japan and Germany have a history of collaboration in scientific and technological endeavours. The countries have a Joint Committee on Cooperation in Science Technology that has met many times over the decades. Both countries have advanced, powerful economies and sophisticated technological know-how, so it makes sense they’d collaborate on scientific activities.

This time, their cooperation concerns a small, potato-shaped chunk of rock: Mars’ moon Phobos.

August 21, 2022August 21, 2022 by Matt Williams

Were Phobos and Deimos Once a Single Martian Moon That Split up? Not Likely, says New Study

A composite image of Mars and its two moons, Phobos (foreground) and Deimos (background). Credit: NASA/JPL/University of Arizona

The origin of Phobos and Deimos, the two Martian moons, has been a mystery to astronomers. These two bodies are a fraction of the size and mass of the Moon, measuring just 22.7 km (14 mi) and 12.6 km (7.83 mi) in diameter. Both have a rapid orbital period, taking just 7 hours, 39 minutes, and 12 seconds (Phobos) and 30 hours, 18 minutes, and 43 seconds (Deimos) to complete an orbit around Mars. Both are also irregular in shape, leading many to speculate that they were once asteroids that got kicked out of the Main Belt and were captured by Mars’ gravity.

There’s also the theory that Phobos and Deimos were once a single moon hit by a massive object, causing it to split up (aka. the “splitting hypothesis”). In a recent paper, an international team of scientists led by the Institute of Space and Astronautical Science (ISAS) revisited this hypothesis. They determined that a single moon in a synchronous orbit would not have produced two satellites as we see there today. Instead, they argue, the two moons would have collided before long, producing a debris ring that would have created an entirely new moon system.

June 20, 2022June 20, 2022 by Matt Williams

Samples of Asteroid Ryugu Contain More Than 20 Amino Acids

Artist's impression of the Hayabusa2 spacecraft touching down on the surface of the asteroid Ryugu. Credit: JAXA/Akihiro Ikeshita?

In 2014, the Japan Aerospace Exploration Agency (JAXA) dispatched its Hayabusa2 spacecraft to rendezvous with 162173 Ryugu, a Near-Earth Asteroid (NEA) that periodically passes close to Earth. In 2018, this sample-return mission reached Ryugu and spent the next year and a half studying its surface and obtaining samples from its surface and subsurface. By 2020, these samples made it back to Earth, where scientists began analyzing them in the hopes of learning more about the early history of the Solar System and answering key questions about the origins of life.

Earlier this year, the first results of the analysis showed that Ryugu is (as expected) rich in carbon, organic molecules, and volatiles (like water) and hinted at the possibility that it was once a comet. Based on a more recent analysis, eight teams of Japanese researchers (including one from JAXA) recently announced that Ryugu carries strains of no less than 20 different amino acids -the building blocks of DNA and life itself! These findings could provide new insight into how life is distributed throughout the cosmos and could mean that it is more common than previously thought.

June 15, 2022June 15, 2022 by Evan Gough

Japan’s Upcoming Mission Will Use a Vacuum to Get its Sample From Phobos

The Martian Moons eXploration (MMX) mission (courtesy: JAXA/NASA).

JAXA, the Japanese Aerospace Exploration Agency, is carving out a niche for itself in sample-return missions. Their Hayabusa mission was the first mission to sample an asteroid when it brought dust from the asteroid Itokawa to Earth in 2010. Then its successor, Hayabusa 2, brought back a sample from asteroid Ryugu in 2020.

Now JAXA has the Martian moon Phobos in its sights and will send a spacecraft to sample it as soon as 2024. The mission is called Martian Moons eXploration (MMX), and it’ll use a pneumatic vacuum device to collect its samples.

June 14, 2022June 14, 2022 by Laurence Tognetti

ESA Gives Green Light on its Comet Interceptor Mission

Comets, with their long, beautiful, bright tails of ice, are some of the most spectacular sightings in the night sky. This was most apparent when Comet NEOWISE passed by Earth in the summer of 2020, dazzling viewers from all over the planet while being mainly visible in the northern hemisphere. Even though the sky might look the same night after night, comets are a humble reminder that the universe is a very active and beautiful place.

March 24, 2022March 24, 2022 by Evan Gough

Asteroid Ryugu Might Actually Be a Dead Comet

egion of the highest resolution image. Yellow boxes correspond to the region in Figure 1. (Left) The region is shown on the ONC-T global image of Ryugu. (Right) ONC-W1 image, taken at 70 m height. 2018-09-21 13:02(JST). Credit: JAXA

In 2014, the Japanese Space Agency JAXA launched the Hayabusa 2 spacecraft to visit asteroid Ryugu. It arrived at the asteroid in June 2018 and studied it from orbit for over a year. Hayabusa 2 even dispatched four rovers to the asteroid’s surface. After departing, it flew past Earth in December 2020, dropping off a sample of Ryugu.

Of all the scientific results from that impressive mission, the most interesting one might be this: Asteroid Ryugu might not be an asteroid. It might be the remnant of a comet.