In an ambitious and unique educational initiative, NASA launched 12.5 million tomato seeds into Earth orbit in 1984 as part of the 'Space Exposed Experiment Developed for Students' (SEEDS) project. The goal was to investigate how prolonged exposure to the harsh space environment might affect seed germination and subsequent plant growth. These seeds, all of the Rutgers California Supreme variety, spent 69 months, or nearly six years, traveling through space before their return to Earth.
A Delayed Return and a Global Classroom
The seeds were carried aboard the Long Duration Exposure Facility (LDEF), a 9.7-ton cylindrical satellite designed to expose various experiments to the vacuum, radiation, and micrometeorites of space. The Space Shuttle Challenger deployed the LDEF on April 7, 1984. Originally slated for retrieval within a year, the LDEF's mission was dramatically extended due to the Space Shuttle Challenger disaster in January 1986, which halted shuttle flights.
Without propulsion, the LDEF slowly lost altitude, eventually dropping to an orbit of about 280 kilometers. It was finally rescued by the Space Shuttle Columbia on January 12, 1990, after completing over 32,000 orbits around Earth. Throughout its extended mission, the tomato seeds remained sealed, exposed to solar radiation, cosmic rays, and microgravity within the LDEF.
The SEEDS Experiment: Students as Scientists
Upon their return, the space-exposed seeds became the centerpiece of one of the largest classroom science projects ever undertaken. Approximately 132,000 planting kits were distributed to teachers at around 40,000 schools across all 50 U.S. states, the District of Columbia, and 30 other countries. Each kit contained both space-traveled seeds and a control group of identical seeds that had remained on Earth.
Students meticulously recorded observations on germination rates, growth patterns, flowering, fruit formation, and the overall condition of leaves and stems. NASA received nearly 8,000 comprehensive reports submitted by participating classes, contributing to a vast dataset.
Unexpected Results and Lasting Impact
Preliminary data from the student observations showed some intriguing, albeit minor, differences. Space-exposed seeds exhibited a slightly higher germination rate (73.8% compared to 70.3% for Earth seeds) and germinated marginally faster, averaging 8 days versus 8.3 days. However, the project's summary ultimately concluded that there were no significant, lasting differences in the overall growth, development, or fruit production between the plants grown from space seeds and those from Earth-bound control seeds.
While the long journey through space did not produce dramatic botanical changes, the SEEDS project left an indelible mark as a pioneering and massive educational endeavor. It successfully engaged millions of students in real-world scientific inquiry, sparking curiosity about space exploration, plant biology, and the scientific method, cementing its legacy as a landmark classroom science experiment involving extraterrestrial materials.