MIO. The name may sound strange and the vehicle itself looks a little unusual. But the van-turned-roving laboratory has a serious, scientific purpose.

The Mobile Ionospheric Observatory -- its formal name -- was designed and equipped by Boston University scientists to take them where the astronomical action is.

The BU astronomers got the idea for the MIO in September of 1982, after they had taken a load of delicate instruments into the jungles of Brazil to monitor a series of rocket experiments.

"We got excellent data on three of the experiments," says BU astronomy Prof. Michael Mendillo, "and none on the fourth. You always like to bat 1,000." They were set to record the fourth launch when an unexpected tropical thunderstorm came up and they had to disconnect their computers and other equipment and get them under cover.

Later, says Mendillo, "We thought, 'If all this equipment had been indoors, we wouldn't have had to pull the plug.' " A self-contained mobile observatory, the professor and his fellow BU astronomers realized, was what they needed. A couple of years later, that's exactly what they had.

"I have to credit my colleague Jeffrey Baumgardner," says Mendillo. "He designed all the equipment and integrated it into this vehicle. It is a unique set of diagnostic equipment."

What Baumgardner did was gut the inside of a traditional motorized van and fill it with miniaturized electronic research equipment. Explains Mendillo, "It has the computer and several pieces of sophisticated observing equipment to either monitor radio signals from satellites or take pictures using a very sensitive, image-intensified camera system."

How sensitive? "It's a state-of-the-art system that allows us to photograph extremely faint signals thousands of kilometers away in space . The signals are electronically amplified before we take the picture. Virtually everything we take pictures of, you can't see."

The MIO more than proved itself Dec. 27 when the National Aeronautics and Space Administration carried out an "artificial comet" experiment. The plan, says Mendillo, was to have three ground-based observatories, the MIO -- as a roving observatory -- and two airborne laboratories, record data as a NASA satellite released Barium gas into the path of solar particles -- "the solar wind" -- 70,000 kilometers from Earth.

"For the experiment to be successful," he says, "three separate observations had to be made so that we could do triangulation and figure out where the comet was as a function of time, to measure the position accurately."

As it turned out, the three land-based observatories -- in Hawaii, New Mexico and Arizona -- all were clouded that night. "The airborne observatories were above the clouds and they got data."

The MIO saved the night. "We decided in advance, based on weather forecasts and the statistics of clear skies at various sites in the western United States, that Boulder, Colo., would be a good place to go."

Mendillo's team shipped the MIO to Denver and drove it from there to Boulder Canyon. "We were the only observatory on the ground that got extensive data," says Mendillo. As the third facility able to record the data, the BU vehicle was what made the experiment a success.