The Tera-hertz Explorer (TEREX) mission is a planned orbiter and lander that will be carrying a terahertz sensor to the surface of

Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury. In the English language, Mars is named for the Roman god of war. Mars is a terrestrial planet with a thin at ...

to measure the oxygen

isotope Isotopes are two or more types of atoms that have the same atomic number (number of protons in their nuclei) and position in the periodic table (and hence belong to the same chemical element), and that differ in nucleon numbers (mass numb ...

ratios of various molecules in the

Martian atmosphere The atmosphere of Mars is the layer of gases surrounding Mars. It is primarily composed of carbon dioxide (95%), molecular nitrogen (2.8%), and argon (2%). It also contains trace levels of water vapor, oxygen, carbon monoxide, hydrogen, and no ...

. The lander, TEREX-1, was originally supposed to launch as a piggyback with another payload during the July 2020

Mars launch window The planet Mars has been explored remotely by spacecraft. Probes sent from Earth, beginning in the late 20th century, have yielded a large increase in knowledge about the Martian system, focused primarily on understanding its geology and habi ...

, but this has subsequently been delayed to 2022 and then to the mid 2020s. As of September 2017, no official launch arrangement with a primary mission had yet been reached. The spacecraft will orbit Mars for a short while before landing the instrument on the surface. A dedicated orbiter, TEREX-2, was planned for launch in 2024. It will conduct a global survey of the Martian atmosphere and surface for water and oxygen levels. The mission is being developed by Japan's

National Institute of Information and Communications Technology National may refer to: Common uses * Nation or country ** Nationality – a ''national'' is a person who is subject to a nation, regardless of whether the person has full rights as a citizen Places in the United States * National, Maryland, c ...

(NICT), and the

University of Tokyo , abbreviated as or UTokyo, is a public research university located in Bunkyō, Tokyo, Japan. Established in 1877, the university was the first Imperial University and is currently a Top Type university of the Top Global University Project b ...

Intelligent Space Systems Laboratory (ISSL). The project is based on a past proposal named FIRE (Far InfraRed Experiment), which was a sensor intended for JAXA's cancelled MELOS Mars orbiter. If successful, it will be Japan's first successful Mars spacecraft since the ill-fated Nozomi mission.

Development

ISSL has previously developed two deep space probes: the

PROCYON Procyon () is the brightest star in the constellation of Canis Minor and usually the eighth-brightest star in the night sky, with an apparent visual magnitude of 0.34. It has the Bayer designation α Canis Minoris, which is Latinized ...

asteroid probe and the

EQUULEUS Equuleus ( ) is a constellation of stars that are visible in the night sky. Its name is Latin for "little horse", a foal. Located just north of the celestial equator, it was one of the 48 constellations listed by the 2nd century astronomer Ptolem ...

CubeSat A CubeSat is a class of miniaturized satellite based around a form factor consisting of cubes. CubeSats have a mass of no more than per unit, and often use commercial off-the-shelf (COTS) components for their electronics and structure. CubeSats ...

mission to Earth–Moon L₂ Lagrangian point. NICT will put into use their experience developing the SMILES (Superconducting Submillimeter-Wave Limb-Emission Sounder) instrument on board the

ISS The International Space Station (ISS) is the largest modular space station currently in low Earth orbit. It is a multinational collaborative project involving five participating space agencies: NASA (United States), Roscosmos (Russia), JAXA (J ...

Kibo module, and SWI (Sub-millimeter Wave Instrument) on board the

Jupiter Icy Moons Explorer The Jupiter Icy Moons Explorer (JUICE) is an interplanetary spacecraft in development by the European Space Agency (ESA) with Airbus Defence and Space as the main contractor. The mission will study three of Jupiter's Galilean moons: Ganymede, ...

, which the institute jointly developed with

ESA , owners = , headquarters = Paris, Île-de-France, France , coordinates = , spaceport = Guiana Space Centre , seal = File:ESA emblem seal.png , seal_size = 130px , image = Views in the Main Control Room (120 ...

and DLR (

German Aerospace Center The German Aerospace Center (german: Deutsches Zentrum für Luft- und Raumfahrt e.V., abbreviated DLR, literally ''German Center for Air- and Space-flight'') is the national center for aerospace, energy and transportation research of Germany ...

). Unlike the Japanese Space Agency ( JAXA), which is under the jurisdiction of the Ministry of Education, Culture, Sports, Science and Technology, NICT's parent agency is the

Ministry of Internal Affairs and Communications The is a cabinet-level ministry in the Government of Japan. Its English name was Ministry of Public Management, Home Affairs, Posts and Telecommunications (MPHPT) prior to 2004. It is housed in the 2nd Building of the Central Common Government Of ...

(MIC). MIC formally approved the Tera-hertz Explorer mission in early 2017.

Spacecraft

The preliminary lander's dimensions are a 50 cm cube, and may have a mass of including propellant. Its landing system is proposed to employ an inflatable

aeroshell An aeroshell is a rigid heat-shielded shell that helps decelerate and protects a spacecraft vehicle from pressure, heat, and possible debris created by drag during atmospheric entry (see blunt body theory). Its main components consist of a heat ...

decelerator, and an airbag.Mars Entry, Descent, and Landing by Small THz Spacecraft via Membrane Aeroshell
Akifumi Wachi, Ryohei Takahashi, Ryo Sakagami, Yuki Koshiro, Yasuko Kasai, Shinichi Nakasuka. AIAA SPACE and Astronautics Forum and Exposition, AIAA SPACE Forum, (AIAA 2017-5313). Published by the Aerospace Research Central.

References

External links

TEREX project website
{{Future spaceflights Missions to Mars Japanese space probes Proposed space probes 2020s in spaceflight 2020s in Japan