Wide varieties of scientific, medical, and educational experiments are conducted on the International Space Station (ISS) – Japanese Experiment Module (JEM).
JEM, also known as Kibo, the Japenese word for “hope”, is the Japanese science module of the ISS and the largest ISS module. JEM provides extensive opportunities for space environment utilization. These includes experiments to be conducted by Japanese astronauts, in-orbit testing of new technologies in actual space environments, as well as launching of cubesats and microsats.
SSTA is Singapore’s sole administrator for the utilization of JEM for education and technical development.
Features of Space Environment
The space environment has features which cannot be easily obtained on the ground, such as microgravity, high level of vacuum, excellent visibility, and space radiation. A variety of fields of research and experiments or observations is expected to utilize these features.
Space provides a large-scale high-level vacuum environment. At the ISS altitude about 400km (250mi), the pressure of the environment is about one 100,000th of 1Pa, which is about 0ne 100 milllionth of the pressure on the ground.
Visibility for observing space is excellent since there is almost no atmosphere and no meteorological effects in space close to the Earth. The whole Earth can be observed from outside of the atmosphere. Abundant, constant, and high-density solar energy is also available.
The space radiation environment is composed of various types of particles. These include a radiation belt consisting of particles captured by the Earth’s magnetic field and surrounding the Earth like a donut; protons with energies ranging from 10 through 1016 Mev; galactic radiation composed of many types of nuclei such as helium, carbon, oxygen, and iron; and high levels of particles generated by solar flares.
Means of Conducting Microgravity Experiments
Space is an ideal place for conducting long-term microgravity experiments while microgravity environment can be obtained on Earth via several means. The means and the comparison are shown in the table below.
|Methods of microgravity experiments||Microgravity level||Duration||Information, Examples|
|International Space Station||10-4～10-6G||Weeks to several years|
|Aircraft||10-2～10-3G||10 to 25 seconds||Weeks to Months|
|Drop Tower||10-3～10-4G||one to ten seconds||Weeks to Months|
|Space shuttle||10-3～10-5G||One to two weeks|
|Free flyer||10-5g or over||Depends on mission duration (about six months)||Weeks to Months|
|Small rockets||10-2～10-3G||Several minutes||Space experiments by launching small rockets|
|Mir||10-3～10-5G||Weeks to Months||Russia’s Mir Space Station|