Back in 2014, I bought some seeds that had been into space. They are cinnamon basil (Ocimum basilicum Cinnamon), still sealed into their space packet. 

According to the description:

“These seeds were flown to space on mission STS-121 aboard the Space Shuttle Discovery and attached to the exterior of the International Space Station on July 4, 2006. The seed remained attached as a component of the MISSE (Materials International Space Station Experiment) and returned to Earth on mission STS-118 aboard the Space Shuttle Endeavour on August 21, 2007.”

There’s a lot of information there to unpack. The first question I asked was whether it could be right that they launched on STS-121 but came back to Earth on STS-118. Weren’t the shuttle missions numbered sequentially? I looked it up, and it turns out that they were, mostly. But they were numbered as they were planned, and not as they were launched, so when missions got moved around in the schedule, their numbering didn’t change. (Wikipedia has a list of all the space shuttle missions, in launch order.) In this particular case, it was the Columbia disaster that forced the changes.

“Before the accident, Columbia had been assigned to missions STS-118 and STS-121. The STS-118 mission, also an International Space Station flight, was at first reassigned to Discovery, but was later assigned to Space Shuttle Endeavour.”


STS-121 was the only shuttle to launch on Independence Day, July 4. It was the second spaceflight for astronaut Mark Kelly, twin brother of Scott Kelly. Also onboard was Piers Sellers, who was born in England. He became an American citizen in 1991 so that he would be eligible to join the NASA astronaut corps. He later became a renowned climate scientist but sadly died in 2016.

A MISSE experiment on the exterior of the international space station
[Image credit: NASA]

MISSE is an ongoing series of experiments that tests how samples and specimens react to exposure to the space environment. As well as seeds, MISSE has been used to test everything from paints and lubricants to fabrics and solar panel technologies.

Fixed to the outside of the ISS for years at a time, the samples are exposed to extreme levels of radiation, temperature fluctuations and the vacuum of space.

The space station was still under construction in 2007, and STS-118 launched with a batch of components for it, with Scott Kelly as the commander of the mission. On August 18 2007, Mission Specialist Dave Williams and ISS Flight Engineer Clay Anderson spacewalked for five hours. They completed a variety of tasks, including retrieving two materials experiment containers to be brought home on the shuttle. 

My seeds were included in Materials International Space Station Experiment-3 and 4 (MISSE-3 and 4), which carried 875 specimens in suitcase-like cases called PECs (passive experiment containers).

“As part of an education outreach program, three million basil seeds were placed in containers located underneath the sample trays on MISSE 3 and 4 PECs. These seeds were returned to Earth as part of the STS-118/13A.1 mission in which Astronaut Barbara Morgan initiated the grown cycle of basil seeds inside the ISS. The seeds were sent to school children for them to plant and observe the differences between seeds exposed to space and seeds that have remained on Earth.”

Glenn Research Center

I love this video of Barbara Morgan explaining what happened inside the space shuttle when they unpacked some of the basil seeds: 

So that’s my space-flown basil seeds. Since they were pretty old by the time they got to me, I have never tried to germinate any of them. However, there are people trying to grow space-flown seeds:

What’s the story behind those seeds? In some ways, it is even more remarkable. In April 1984, NASA sent canisters containing 12.5 million Rutgers California Supreme tomato seeds as part of the Long Duration Exposure Facility (LDEF) experiment. LDEF was a cylindrical satellite, about the size of an American school bus, and Challenger mission STS-41-C deployed it into a low Earth orbit. 

The aim of the Space Exposed Experiment Developed for Students (SEEDS) experiment was to see how exposure to weightlessness and radiation affected the growth of the seeds. The plan was that Challenger would collect the LDEF during mission STS-51-L in January 1986, but that flight ended in disaster. The seeds finally got a ride home on Columbia in January 1990. 

The Long Duration Exposure Facility (LDEF) is lifted over Challenger’s payload bay on mission STS 41C
[Image credit: NASA]

After six years in space, schoolchildren all over the world grew the space-exposed tomato seeds and compared them with their Earth-bound counterparts. NASA did have to reassure parents and teachers alike that their extended stay in space would not have turned them into “killer tomatoes“. But due to the efforts of those intrepid students (and seeds!), NASA discovered that seeds can survive in space for long periods with little or no change in the resulting plant. Indeed, NASA’s press release on the project reported that “many student researchers were disappointed not to see drastically altered mutant plants and fruit.”

“Of the 8,000 reports returned to NASA, the findings suggest that the space-exposed seeds germinated slightly faster. In addition, the space-exposed seedlings had a faster initial growth rate, observed for the first 3 or 4 weeks of growth. Eventually, the Earth-based seedlings caught up with their counterparts and overall, no differences were found between the two types of plants or their fruits.”

NASA Press Release 92-49

It’s one of NASA’s more fascinating press releases, and there are some hilarious excerpts from the student responses:

“Dear NASA: Hi, My name is Matt. I am in grade 2. I really enjoy growing my plants. Here are my results. My Earth seed did not grow. My space seed grew but it fell off my desk. It died.”

A child in Ontario

A parent in Portland, Oregon reported that his child’s space plants were severely damaged by his 4-year-old stepsister’s “Michael Jordan 3-point shot”. However, both plants survived the assault, and one went on to produce a tomato that won the Youth Division Vegetable Oddity Blue Ribbon at the Oregon State University Extension Seed Harvest Fair. 

“Made enough Gazpacho for a week.” 

Anonymous SEEDS student researcher

One teacher planned to make tomato jam as Christmas presents. Another, based in California, “raced the nation in producing the first ripe space tomato. To celebrate, his classes organized the first Bacon, Lettuce and Space Tomato Sandwich Party.”

Sounds like they all had a blast!

“We sincerely hope the learning from SEEDS will continue for many years to come… for someday these budding scientists will be the experimenters and explorers on Space Station Freedom and at the lunar outpost, and they will be the first Martians.”

NASA Administrator Daniel S. Goldin

The space-flown seeds didn’t fare as well on this side of the Atlantic, unfortunately. Reginald Turnill, who had covered the Apollo rocket launches as the BBC’s aerospace correspondent, had arranged with NASA for some of the tomato seeds to be brought to the UK. His plan was for them to be grown on the Blue Peter children’s television show, and to be distributed to British schools. The plan fell foul of “The Ministry”, as the seeds did not have an import license!

And that’s not even the end of the story! In 2017, packets of the space-flown tomato seeds made their way to Italy and then to Australia. Unaccompanied by the proper paperwork, once they arrived in Sydney, the seeds only made it past the Biosecurity Officers after being blasted by gamma rays.

“All seeds or plant material imported to Australia must meet our biosecurity conditions regardless of the country, or galaxy, they’ve arrived from. These particular seeds posed a relatively low risk, as they did not encounter alien life forms when in orbit and the importer is keeping them on display as a collector’s item and not for sowing purposes.”

Head of Biosecurity Operations, Nico Padovan, via SBS News
Grow your own space lettuce! Outredgeous seeds are available from Suttons in the UK
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