SpaceX founder Elon Musk in Seattle announcing plans to build a 4,000-satellite constellation. Credit: Washington Aerospace Partnership via Twitter

WASHINGTON — SpaceX is planning to launch a series of experimental low Earth orbit communications satellites starting next year to test technologies for a future low Earth orbit (LEO) satellite constellation the company announced earlier this year.

In a May 29 filing with the U.S. Federal Communications Commission, SpaceX sought an experimental Ku-band communications license for two spacecraft, named MicroSat-1a and MicroSat-1b, that it plans to launch in 2016 on a Falcon 9. The satellites will operate in near-polar orbits at an altitude of 625 kilometers.

The company said the two satellites are the first of series of six to eight “test and demonstration” spacecraft the company plans to launch. “These are prototype engineering verification vehicles that will enable in-space performance assessment and rapid iteration of technologies,” the company said in its filing. “A main objective of the test program is to validate the design of a broadband antenna communications platform (primary payload) that will lead to the final LEO constellation design.”

SpaceX said in its FCC application that will test the satellites using three ground stations. One will be located at SpaceX headquarters in Hawthorne, California. A second will be at what SpaceX calls its “commercial satellite development center” in Redmond, Washington. The third will be at the Fremont, California, headquarters of Tesla Motors, the electric car company that, like SpaceX, is run by Elon Musk.

The FCC application offered few details about the two spacecraft themselves. The spacecraft, identical to each other, are designed to operate for six to twelve months, but SpaceX said it would consider operating them beyond that period “until such time as the primary mission goals can no longer be met.” The orbit inclination and small size implied by the “MicroSat” name suggests the satellites will be launched as secondary payloads on a mission from Vandenberg Air Force Base in California.

In a speech in Seattle in January, Musk said SpaceX was planning a 4,000-satellite constellation to provide broadband Internet access, and had submitted filings for that system to the International Telecommunication Union. He did not give a specific schedule for developing that system.

The FCC application also did not provide a schedule for that full-scale system, other than it plans to deploy the constellation “in the near future.”

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...