The U.S. space agency says it is starting an initiative to launch small cube-shaped satellites for educational and not-for-profit organizations.

NASA said the satellites, nicknamed CubeSats, are a class of research spacecraft called picosatellites, having a size of approximately four inches, a volume of about one quart and weighing no more than 2.2 pounds.

The Monday announcement is NASA's first open announcement to create an agency-prioritized list of available CubeSats. They are planned as auxiliary payloads on launch vehicles already scheduled for 2011 and 2012.

"We're anticipating some exciting proposals for this pilot program with hopes to break down the barriers to the launching of CubeSats," said Jason Crusan, chief technologist for NASA's Space Operations Mission Directorate. "There are organizations that have been waiting a long time for a chance to see their satellites fly in space."

Officials said collaborators will be required to provide partial reimbursement of approximately $30,000 per CubeSat since NASA will not provide funding to support CubeSat activity or development.

Proposals must be submitted electronically and be received by 4:30 p.m. EDT April 15. Selection is anticipated by June 30, officials said.

More information is available at http://prod.nais.nasa.gov/cgi-bin/eps/synopsis.cgi?acqid=139845.