If bad weather or a minor technical problem scrubs the launch attempt Tuesday, there is another chance to fly on Wednesday. After that, however, Boeing will have to wait for NASAs space shuttle to fly on Friday before getting another turn on the Eastern Range.

This will be the seventh time that a Boeing Delta 2 rocket is to carry four of the Globalstar satellites on a single mission. Six Delta 2 missions during the past two years have launched 24 of the spacecraft into orbit.

"We've done a lot of business together and had a lot of success and I certainly intend wholeheartedly to continue that streak," Rich Murphy, Boeings director of launch operations, said Monday.

Six Russian Soyuz rockets launched the other 24 satellites from Kazakhstan.

After these four new satellites are in orbit, Globalstar will rearrange their spacecraft so that of the total 52 in space, 48 are declared operational and four are treated as spares, said John Klineberg, president of Space Systems Loral.

Although there is no need for any spares just yet, Globalstar managers say they want to be prepared to move quickly should an operational satellite fail.

"The satellites have been working very, very well," Klineberg said, noting that they are designed to last at least 10 years in low Earth orbit, but exposure to radiation and atomic oxygen molecules in space will eventually damage the satellites.

With that in mind, Globalstar has ordered Space Systems Loral to build eight more satellites and has procured two more Delta 2 rocket flights from Boeing, but it will probably be two years or more before any of the hardware is launched.

When they fly, the additional Globalstar spares will ride on the same version of the Delta 2 rocket being used on Tuesday the 7420 model. This Delta 2 model has only four strap-on solid rocket boosters instead of the nine boosters used on all other Delta 2 missions.

The Globalstar satellites dont weigh as much and dont have to go as high as other communication satellites launched by Boeing, so they literally dont need as much rocket power.

All four of the solid rocket boosters ignite on the ground along with the first stage Rocketdyne main engine. The solids burn out and are jettisoned from the rocket 67 seconds after launch.

If all goes well during Tuesdays launch, a small camera inside the Delta rocket that points forward will show the rockets nosecone separating and then, later, the four Globalstar satellites being deployed.