Sirius XM Radio has been bailed out of immediate problems but at a high price. Liberty Media will loan the satellite radio operation a total of over a half a billion dollars at an interest rate of 15%, secured against substantially all its assets, in return for a 40% equity stake. That will enable Sirius XM to repay bonds due to satellite television company EchoStar and avoid the need to seek bankruptcy protection. It is unlikely to be enough to save Sirius in the longer term, but it looks like a characteristically clever deal that gives Liberty a strong claim over the company and its satellites.

John Malone, the chairman of Liberty Media Corporation, will join the Sirius XM board. The loan will come from the Liberty Capital Group. Liberty Media also has an interactive group, which includes interests in QVC and Expedia, and an entertainment group, which has interests in DIRECTV and Starz Entertainment, among other media interests.

Greg Maffei, the chief executive of Liberty is also expected to join the board. “Sirius XM’s ability to grow subscribers and revenue in a difficult financial and auto market is indicative of how listeners view this as a ‘must have’ service,” he said.

“We are pleased to have come to this agreement with Liberty Media, particularly in light of today’s challenging credit markets,” said Mel Karmazin, the chief executive of Sirius XM Radio. “This agreement enables Sirius XM to continue to develop the opportunities first outlined in the merger of Sirius and XM.”

Ironically, the $6 billion of losses built up by Sirius XM could be its biggest asset, which Liberty can use over time to offset against taxable revenues.

There are potential synergies between DIRECTV and Sirius XM which could be used to bundle the service to satellite television subscribers, offer more channels of mobile video for in-vehicle entertainment, or simply use the spectrum and terrestrial repeater network to offer other services.