A NASA Mars Orbiter will make it possible for manned missions, but food on the red planet could be a problem.

The Mars Reconnaissance Orbiter made its descent into the atmosphere of Mars at about 3:30 p.m. on March 10.

The Orbiter, which was in transit for seven months, will inspect potential landing sites for future manned missions, according to NASA’s Web site.

But a potential landing site isn’t the only issue when it comes to sending people to Mars.

Making sure the astronauts have a constant, quality food source is a major factor in a successful mission, and that’s where NASA’s Food Technology and Commercial Space Center comes in.

There are many problems that are facing scientists as they try to plan how to get food to Mars and how much is needed.

“The goal is that 90 percent of the food needed comes from what can be grown,” said Anthony Pometto, former director of NASA’s Food Technology and Commercial Space Center and professor of food science and human nutrition. “Over 3,000 pounds of food and 23,500 pounds of water per person, and the heavier the load, the more fuel needed – and the more expensive it gets. So the less we have to bring, the better.”

The current shelf life of packaged food is about three years, but NASA wants to raise that to five years by the time the mission is ready to go.

Creating the right amount of pressure in the packages is one key to longer-lasting food.

“If you reduce the pressure after the bags are full, they will start to blow up,” said Lester Wilson, professor of food sciences and human nutrition. “It’s sort of a pillow effect.”

Not only must the packaging withstand the dramatic changes in pressure, but it must be shield the food from radiation that could affect its functionality.

So as not to jeopardize the integrity of the planet, the missions must be 100 percent self-sufficient.

“They are not to use material from or put anything into the environment,” Wilson said.

Food preparation techniques must also be changed. All the items in a usual kitchen must be shrunk down to easily fit in a shuttle or station, and the preparation must be closely monitored.

“It’s not just like walking into a kitchen where if you burn something you can just open a window,” Pometto said.

To cut down on unnecessary items, a different style of food production called hydroponic agriculture is being used.

In this method, the nutrients float in water that is bathing the roots. The plant sucks up the nutrients, and the water can be recycled. The lighting, heat and air are controlled to create the best environment.

Growing food has advantages beyond saving money and space on the mission. The plants turn the carbon dioxide the astronauts create into oxygen, creating a fresh air cycle.

“There is a psychological benefit to growing plant for the astronauts,” Pometto said. “It goes beyond just food.”

As of now there is no timetable for a manned mission to Mars, but this orbiter could provide some answers.

“Ideally what we are looking for is a place where minerals indicate water was there for a long time,” said Sue Smrekar, deputy project scientist for the Mars Reconnaissance Orbiter. “Astronauts need subsurface ice for fuel.”

The Orbiter is equipped with a to find water-related deposits and radar to look for water or ice. This mission should collect more data than all previous Mars missions combined.

A new rover will be sent in 2009 to test a potential site that could be used for a manned spacecraft landing.