Satellites are devices launched into orbit to collect information or aid in communication. Although they're invaluable tools, they also are enormously expensive to send into space. But using an amazing adaptor called an ESPA ring, engineers at an Air Force research lab in Albuquerque, New Mexico are helping send up more satellites by adding them to existing, larger missions. An ESPA is fitted between a launch vehicle, or the rocket, and the primary satellite and can hold up to six small satellites. Before ESPA existed, space engineers would put ballast weight into the payload attach to get the correct performance out of the rocket. ESPA gives the Air Force a much better use for that weight capacity because a rocket that used to only carry one satellite now can take many. "ESPA satellites are kind of riding as second-class citizens -- hitchhiking, if you will," says mechanical engineer Janice Stuart. "Satellites that couldn't afford to be launched are now getting into orbit, making important research possible."