Space Seeds Return to Earth

Seed pods from a commercial gardening experiment aboard the ISS are back on our planet. The far-out pods could hold the key to long-term habitation of space.

When the space shuttle Atlantis returned to Earth in July 2001, it brought home some unusual cargo - seed pods grown in space. They were the harvest of an 8-week-long commercial gardening experiment on board the International Space Station (ISS). Astronauts on the ISS have been tending a batch of fast-growing Arabidopsis plants (better known as "mustard weed") to discover whether plants can complete their entire seed-to-seed life cycle in a weightless environment.

Video from the experiment shows that seed pods were produced by the space-borne plants. But scientists aren't yet certain what's inside the pods.

"We are waiting for retrieval of the payload to see whether or not seeds are indeed inside the seed pods," says Weijia Zhou, Principal Investigator for the ADVANCED ASTROCULTUREtm plant growth chamber that harboured and nourished the seedlings on the ISS. "Personally, I have a very high confidence level that they will have seeds," he added.

Zhou is the Director of the Wisconsin Centre for Space Automation and Robotics (WCSAR), a NASA Commercial Space Centre that built the growth chamber. "This research is a joint endeavour between WCSAR and Space Explorers, Inc. (SEI)," explains Zhou. SEI is a private company specialising in the development of educational products for schools. Data from the ADVANCED ASTROCULTURE^TM experiment will allow SEI to complete an Internet-based multimedia program called Orbital Laboratory, which students and educators can use to study plant biology in classrooms.

If normal, healthy seeds were produced as Zhou suspects, the experiment will be a good sign that future astronauts can grow multiple generations of plants in space. Such self-perpetuating gardens will be a practical necessity for humans as they explore and colonise the solar system. Hardy space plants could provide fresh food, oxygen, and even clean water for explorers living for long stretches aboard orbiting outposts or on the Moon and Mars.