Among the most common questions people have about spaceflight are what kinds of foods do astronauts eat, and how do they eat them in orbit. Through the Space Food Systems Laboratory at the Johnson Space Center and the Food Technology Commercial Space Center at Iowa State University, NASA's Office of Biological and Physical Research has a hand in serving up the answers for public consumption.

Fortunately for crewmembers, the pantry is well-stocked during missions. Due to American and Russian astronauts sharing living space aboard the ISS, NASA provides half the food supply, and the Russian Space Agency furnishes the other half. Entrees such as beefsteak, chicken teriyaki, scrambled eggs, and beef stroganoff with noodles make up the NASA menu, while the Russian ration includes chicken and rice, fish, ham omelets, and prune omelets. Both menus also feature an assortment of fruits, vegetables, and snacks.

Above: Commander Yury Usachev (middle) and Flight Engineers Susan Helms and Jim Voss hang around the dinner table with drinking straws in hand in the Zvezda Service Module during the Expedition 2 mission aboard the ISS in 2001. Credit: NASA/Johnson Space Center. Source: NASA Human Spaceflight Web site (http://spaceflight.nasa.gov) .

The groceries from each country arrive at the station on separate pallets but are stored inside the same cabinet, which is located in the Zvezda Service Module, where the station's galley is located. The Russian Space Agency primarily uses cans to preserve its food; NASA uses flexible foil packaging to maintain food preservation and to help trash compaction. American food stored on the ISS is prepared at the Space Food Systems Laboratory at Johnson Space Center in Houston, Texas. Food prepared for the station must be able to stay stable at room temperature for nine to 12 months, because there is no refrigerator or freezer on the station. It would take a lot of power to keep a re-frigerator running.

The space dining experience has improved immensely since the earliest crewed flight missions. On Mercury's first flight to orbit in 1962, astronaut John Glenn found eating fairly easy, but the menu was limited to bite-size cubes of gelatin-coated food, freeze-dried powder, and semi-liquids in aluminum tubes.

By the time the Gemini missions took place in the mid-1960s, improved packaging boosted the quality of foods. Gemini astronauts enjoyed selections such as shrimp cocktail, chicken and vegetables, and butterscotch pudding. The Apollo program not only put a man on the Moon but also put hot water inside the spacecraft, which made rehydrating foods easier. On the space shuttle and the ISS, crews prepare food much as they might a prepackaged convenience meal at home - minus the microwave. Each astronaut opens a food package; adds water if needed at the rehydration station; pops it in the forced-air convection oven, which takes about 20 minutes to reheat food items due to low power input; and finally consumes the meal using regular utensils on a tray attached to his or her lap.

But even with the improvements in space fare, there are still some challenges to dining in orbit. As soon as crewmembers enter the microgravity environment, they experience a fluid shift. Some of the fluid normally in the lower body shifts to the upper body, leaving the crewmembers with a slight congested feeling. This affects the way foods taste in much the same way having a cold does. To make up for this, crewmembers often douse their food with hot sauce and ketchup to liven up the flavor.

"We see this happening a lot on the space shuttle," says Vickie Kloeris, sub-system manager for space shuttle and space station food at the Johnson Space Center, "but on ISS what we're seeing more is the crewmembers want to add condiments to relieve some of the boredom with the food."

Limited food selection is a challenge. It is difficult to supply enough variety for a whole ISS mission increment, as Flight Engineer Jim Voss discovered firsthand. "I enjoyed all the food during the five and a half months I was there," says Voss. "The Russian au gratin potatoes were especially good, but the menu did get old after about four months of eating menus on an eight-day rotation."

To help break up the monotony, there are usually two space shuttle visits that deliver a bonus container about the size of a lunchbox filled with items not included in the baseline menu such as candy, cookies, preferred store-bought items, and fresh fruit.

A future goal for ISS menu planning is to provide appropriate ethnic foods for crewmembers of varying nationalities and religious beliefs. Among the active payload specialists and career astronauts, 40 are from countries other than the United States and Russia, and their home cuisines are not represented in current ISS selections. For now, says Charles Bourland, former manager of the Space Food System Laboratory, international crewmembers usually bring a few food items from their own countries as token samples. This also holds true for American astronaut Ed Lu, who will take some Asian dishes when he embarks on Expedition 7 to the ISS, slated for launch in early 2003. As for Payload Specialist Ilan Ramon, an STS-107 astro-naut from Israel, his token samples will be kosher, or ritually fit for use according to Jewish law (not all of Ramon's food will be kosher, but his menu selections were chosen using kosher guidelines). Ramon's kosher food is commercially purchased. "All we do is wash the pouch, put a label on it, and stow it in the tray," Kloeris says.

This tradition is likely to continue to accommodate crewmembers not from the United States or Russia, and alternative solutions to providing a taste of home may be on the horizon. The National Space Development Agency of Japan (NASDA) has expressed interest to NASA in providing a portion of the food supply for Japanese crewmembers aboard the ISS.

The FTCSC is an OBPR-funded communication center that encourages faculty and commercial involvement with long-term space food research. Through workshops, student contests, and outreach, the FTCSC not only brings more minds to the table, but also en-riches public awareness about space research.