Researchers hunting for new and profitable fragrances have discovered that roses in Earth orbit don't smell the same as they do on Earth. Soon a pair of flowers will blast off on board the space shuttle where they will participate in the continuing search for exotic space scents.

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Shakespeare knew a few things about romance ... and roses. But here's something he never considered: roses in space. Would they smell as sweet in Earth orbit?

It's not as silly as it sounds--at least perfume industry giant International Flavors & Fragrances (IFF) didn't think so. New fragrances are much sought after in the competitive perfume industry. Some years ago IFF researchers began to wonder, Could space-traveling flowers yield something new and exotic? The answer might prove profitable, they figured.

Right: This miniature rose called "Overnight Scentsation" was cultivated by IFF researcher Dr. Braja Mookherjee for experiments in space. Credit: International Flavors and Fragrances.

And so began perhaps the most romantic space experiment ever done.

In 1998, IFF teamed with the Wisconsin Center for Space Automation and Robotics (WCSAR), a NASA Commercial Space Center (CSC) at the University of Wisconsin. WCSAR's job is to help companies research new products in space. NASA's Space Product Development program at the Marshall Space Flight Center supports 15 such CSC's around the country.

WCSAR researchers had developed a plant growth chamber called ASTROCULTURE^TM for the middeck of the space shuttle. It provides plants with the appropriate temperature, humidity, light, and nutrients during spaceflight, explains Dr. Weijia Zhou, WCSAR director. ASTROCULTURE^TM was perfect for IFF's purpose, and so on Oct. 28, 1998, a tiny rose selected by IFF was able to leave Earth for a 10-day flight onboard the shuttle Discovery (STS-95).

Right: The ASTROCULTURE^TM plant growth chamber. [more]

IFF researchers quickly learned that what we call a rose does indeed smell sweet in space ... but it does not smell the same.

Here's why:

Fragrance, in flowers, is a variable and elusive commodity, evolved solely to help plants reproduce by attracting the insects and animals they need to spread their pollen, or sperm, around. Although we tend to think of floral smells as sweet and appealing, flowers produce a variety of odors, depending on the preferences of their pollinators. If bees are lured by the same kinds of smells that we like, carrion flies, for example, may be drawn by ranker odors, like that of skunk cabbage.

But whatever they smell like, the odors themselves come from "volatile oils," also known as essential oils, because they carry the essential fragrance of the plant. These highly concentrated plant extracts all share certain traits: For example, they readily bind to receptors in olfactory neurons. They also tend to be soluble in alcohol, but not water, and they often feel oily. Most important is that they evaporate at room temperature. Indeed, the fragrances used in perfumes are classified on a scale from 1 to 100, according to how readily they dissipate.

A plant's production of volatile oils is strongly affected by its environment, explained Dr. Braja Mookherjee, who, until his recent death, was Director of Global Natural Products at IFF. Some plants, for example, produce more oils at night when their pollinator is active, and some produce more in the daytime. Temperature, humidity, and the age of the flower are influential, too.

It's no wonder, said Mookherjee, that low-gravity should affect a flower's smell just as other environmental factors do.

Left: Space-scent researchers Braja Mookherjee (IFF Director of Global Natural Products) and Subha Patel (IFF Sr. Research Chemist). Credit: International Flavors & Fragrances.

The flower that flew on STS-95 was a miniature rose called "Overnight Scentsation"--a plant no more than seven inches high, with two buds just ready to open. The rose needed to be small to fit inside ASTROCULTURE^TM, which is a 17 by 9 by 21 inch enclosure.

"Ninety-nine percent of miniature roses have no odor," said Mookherjee, but Overnight Scentsation is an exception. It emits a fragrance, which Mookherjee described as "a very green, fresh rosy note."

In low gravity, said Mookherjee, the rose actually produced fewer volatiles than it did on Earth. But the fragrance that it did generate was critically altered.

And, no, the astronauts didn't just sniff the flower.

To collect the scent, they reached into the ASTROCULTURE^TM chamber and touched the rose using a tiny silicon fiber. Less than one centimeter long, and only 1 to 2 millimeters in diameter, the fiber was coated with a special liquid to which molecules around the flower petal adhere. After the shuttle returned to Earth, IFF researchers took the fiber and analyzed the molecules they found on it.

"We identify the constituents, we know the quantity, and then we can synthesize [the fragrance] here in the lab," explained Mookherjee. The fragrance of a rose is made up of nearly 200 different compounds, he added.

Right: A lab technician demontrates the use of a silicon fiber to collect scent-molecules from a rose. Credit: International Flavors & Fragrances.

The rose was sampled four times throughout the STS-95 shuttle mission. Each time, says Mookherjee, they got a different result. The scent that they finally arrived at was the average of those samplings, and the new fragrance has since been incorporated into "Zen", a perfume produced by the Japanese company Shiseido.

The collaboration between IFF and WCSAR will continue on STS-107, a shuttle mission slated for launch in January 2003. This time the plan is to send up two different plants--a rose and an Asian rice flower--again placed in the ASTROCULTURE^TM facility. Like Romeo and Juliet, the flowers will touch each other. This as well as the low gravity, said Mookherjee, will alter the molecules they emit.

The ability to do research in space, concluded Mookherjee, gives a whole new dimension to the field of fragrance studies. "It's a fantastic opportunity," he said ...one that the Bard himself might have appreciated.

Web Links

Space Product Development (NASA/SPD ) -- The goal of NASA's Space Product Development (SPD) program is to help American businesses explore the potential--and reap the rewards--of doing business in space. Doing this helps bring the benefits of space down to Earth where it can, and does, enrich the everyday lives of the American public. "Industry investment in space is high," says Mark Nall, manager of NASA's SPD program at Marshall Space Flight Center. "We assist companies developing experiments and help them explore how space research can contribute to the growth of their businesses."

The STS-107 research mission (NASA/OBPR ) -- Space-traveling roses are merely one of 80 wide-ranging experiments that will take place during this much-anticipated flight of the shuttle Columbia in January 2003. See also the STS-107 ASTROCULTURE^TM fact sheet.

Wisconsin Center for Space Automation and Robotics -- A NASA Commercial Space Center at the University of Wisconsin. The ASTROCULTURE^TM facility was designed by WCSAR researchers.

Solid-phase microextraction (SPME): During STS-95, astronauts collected scent-molecules from the tiny rose using a technique called solid-phase microextraction (SPME). The SPME device looks much like a syringe, but instead of a needle, it has a tiny silicon fiber less than one centimeter long and only 1 to 2 millimeters in diameter. The fiber was coated with a liquid to which molecules around the flower petal would adhere. For IFF, WCSAR scientists modified the enclosed ASTROCULTURE^TM growth chamber to accommodate the SPME equipment. The changes allow the astronauts to work the tiny device from outside the box, using video equipment so that they can see where to place it.

more: Space Research Results in Unique Fragrance Note (IFF) IFF and WCSAR to conduct "space flower" experiment on NASA space shuttle (IFF); ASTROCULTURE on STS-95 (WCSAR); Space Rose Pleases the Senses (NASA Spinoffs)