Japanese Lunar Exploration: Robots Now, People Later

By Keith Cowing
October 31, 1999
Filed under ,

The Canadian Space Agency (CSA) held the Second Canadian Space Workshop at the University of Calgary in Calgary, Alberta last week. The workshop was intended to provide the Canadian space exploration community with “an
opportunity to propose new ideas, assess potential scenarios, and to identify potential Canadian capabilities and technologies in the space exploration field.” The outcome of the meeting will be used to help shape Canada’s future space exploration activities.

Among the presenters was Koichiro Tsuruda from the Japanese Ministry of Education’s Institute for Space and Astronautics (ISAS). Tsuruda spoke most enthusiastically about Japan’s upcoming missions to the
moon. His particular attention was focused upon the “Selene” mission.

Selene is named after the Moon goddess of Greek mythology. The word is also an acronym which stands for “SELenological and ENgineering Explorer”. This mission will be developed and managed in Japan by ISAS.

Planet-A impactorSelene is scheduled for launch aboard an H-IIA rocket in 2003. After a five day trip it will enter an elliptical orbit around the Moon. As Selene begins to lower its orbit, it will release a relay satellite that will remain in an elliptical orbit with an apoapsis (or maximum distance) from the moon of 2,400 km. The relay satellite will serve to relay information between Selene and Earth. Selene will then lower its down to a more circular orbit with an altitude of 100 km.

Selene will orbit the Moon for approximately one year. During this time it will make surveys of the Moon’s mineralogical composition and map variations in its gravitational field. At the end of this survey, expected in 2004, Selene will separate again, this time into two parts – the propulsion module and the Selene lander. The lander will then proceed to make a soft landing on one of the Moon’s large flat “seas”. On the surface, the lander will perform studies aimed at understanding the technology required for temperature control and energy storage on the lunar surface.

Selene will be Japan’s second mission to the moon – its first, Lunar A will be launched in 2002. Lunar-A will orbit the Moon for approximately one year and will use the LIC camera to observe the Moon’s surface. Shortly after entering orbit, Lunar A will eject two penetrator probes 13 centimeters in diameter and 90 centimeters long. Upon impact, the penetrators will be buried approximately two meters under the Moon’s surface and will radio back readings on seismic and temperature events to the Planet-A spacecraft.

The target impact points for the penetrators are in the general proximity of the Apollo 12 landing site in the Sea of Storms – a location which is also the Surveyor III landing site.

Lunar-A was originally planned for launch in January 1999. However, problems with the penetrator probes and caused a delay. This delay resulted in increased shadow exposure for the probe and an increase in battery requirements, thus forcing the deletion of one penetrator from the three that were originally planned. The mission has been rescheduled for a 2002 launch.

Japan speaks of these two missions in the context of being the beginning of a 30 year plan to explore the Moon – one that will start with unmanned landings and eventually lead to the establishment of a manned base.

SpaceRef co-founder, Explorers Club Fellow, ex-NASA, Away Teams, Journalist, Space & Astrobiology, Lapsed climber.