What 30 years of experiments in space have brought

Despite bad weather, Kennedy Space Center in Cape Canaveral, Florida, is ready for launch.

The final experiment of the NASA space shuttle Atlantis is the center of attention. The craft will carry four astronauts and 30 mice.

The purpose of the experiment is to conduct tests on animals for a new drug for osteoporosis developed by Amgen, a U.S.-based biotech company. Space provides the best conditions for tests on the disease because calcium in bones decreases an average of 1 percent per month in space.

The space shuttle will also carry arabidopsis thaliana, which astronauts will use to test how plants react in zero gravity.

The following are five unique and interesting experiments conducted in space shuttles.

Salmonella, a cause of food poisoning, was carried to space by the space shuttles Atlantis (2006) and Endeavor (2008). Surprisingly, the bacteria got three to seven times more virulent in space.

Living in space for 12 days, salmonella was injected into mice but only 10 percent of the salmonella survived. In contrast, 40 percent of mice survived after the injection of the bacteria that stayed on Earth.

Scientists assume that the DNA of the bacteria was transformed in space to become more virulent. This is because they found that 167 genes and 73 proteins in the DNA of “space salmonella” were changed. Astrogenetics, a U.S. biotech company, developed a salmonella vaccine based on it.

What about the smell of a rose in space? In 1998, the Discovery carried two roses to the International Space Station. The odor changes depending on where roses are grown, so soil, light, temperature and humidity are major factors. In zero gravity, the smell was much more mysterious and sweet.

Discovery astronauts brought the smell of a “space rose” back to Earth after sealing a small stick coated with the rose smell.

Shiseido Cosmetics of Japan launched “Zen,” a perfume using the space odor. In 2007, NASA put another rose on a space shuttle but that flower was destined for the annual New Year’s ceremony in Pasadena, California, not a perfume.

The trip of the space shuttle Columbia on Nov. 29, 1983, marked the first time that the mission of all astronauts was to conduct science experiments. Back then, they conducted experiments in space at Space Lab performed on the 10-day flight.

Space Lab is a reusable laboratory for space shuttles equipped with devices necessary for experiments and served as a venue for 22 space experiments until 1998.

If protein is crystallized in space, it grows freely because they are free from gravity. There is no foreign matter in the crystal because of lack of convection current. In other words, a perfect protein crystal is created.

A three-dimensional structural analysis of the crystals can be used to predict the efficiency or toxicity of potential new drugs. Korea’s first astronaut Lee So-yeon conducted the analysis in 2008.

The tardigrade, a kind of insect, hitched a ride on the space shuttle Endeavor, which was retired after its final trip last month. Though just 1.5 millimeters long, the “hardest animal on Earth” is known as a good survivor.

The insect appeared in the Cambrian period 530 million years ago and has survived temperatures as high as 151 degrees Celsius and as low as minus 273 degrees, or absolute zero. The tardigrade was discovered in the Himalayas 8,000 meters above sea level and 4,000 meters below sea level in the oceans.

Even exposure to 1,000 times the lethal dose of radioactivity to humans does not kill the insects. Scientists hope to find a clue from tardigrades to preserve human life.

Sand has also been used as a material in space experiments. Sand was onboard three space shuttles –- Atlantis (1996), Endeavor (1998) and Columbia (2003), which exploded while returning to Earth.

To build a sand castle, sand should be neither too dry nor too wet because the surface tension works as a cohesive of sand grains. The characteristic was found only a decade ago.

Astronauts tested sand in zero gravity to understand why the earth moves like liquid when an earthquake strikes.

uneasy75@donga.com