By Mark Brown, Wired UK

The Japanese Space Agency (JAXA) has sent an aquarium to the International Space Station. Its not for relaxation, mind: the fish tank will be used to see how microgravity impacts marine life, including a transparent fish.

First up, researchers plan to examine the Medaka (Oryzias latipes) fish, and look at the impacts of radiation, bone degradation, muscle atrophy, and developmental biology.

Medaka is a perfect specimen for research: the astronauts can see their organs through their transparent skin and they breed quickly in microgravity environments. Plus, the animals genome has already been fully sequenced, so it will be easy to recognise changes to the fishs genes.

Water habitats have been launched into space before, but this AQH facility will feature an improved water circulation system that monitors water conditions and removes waste, while ensuring proper pressure and oxygen flow rates.

The special bacteria filter purifies waste materials, such as ammonia, so that we can keep fish for up to 90 days, said Nobuyoshi Fujimoto, an engineer at Jaxa. This capability will make it possible for egg-to-egg breeding aboard station, which means up to three generations may be born in orbit. This would be a first for fish in space.

While the currently planned investigations only use fish, the air-water design of the facility means it could potentially house amphibians. Thats right: space frogs.

Images: JAXA

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