You won’t be able to hear it without a computer or a phone and you probably won’t be able to see it, either — at least not without binoculars — but hey, it’s a big deal when two Seattle icons have a meeting in the middle of the sky, right?

That’s what’s happening Thursday when seminal grunge band Mudhoney plays a live broadcast from the roof of the Space Needle to kick off Sub Pop Records’ Silver Jubilee. Video and audio streams of Mudhoney’s rooftop show will be broadcast live at 5 p.m. by radio station KEXP 90.3 FM.

Sub Pop is the label that launched Nirvana and put Seattle on the pop-music map in the early ’90s. Five years ago, for its 20th anniversary, the outfit flew a flag and had its name painted on top of the Needle, but sending a band up there is a new idea.

“This is the first time in our history that a band has played live from the roof,” said Space Needle public-relations manager Sean Marshall.

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When people imagine the top of the Needle, said Marshall, they think of harnesses and such, but, in fact, the musicians won’t need any special equipment — except their instruments.

“There’s actually a platform up there,” Marshall explained. “Access is internal, on a stationary, built-in ladder.”

The area where the band plays is flat, too, perched on top of the more familiar sloping disc you normally see.

Notices of the Mudhoney performance have been circulating for days, but details of this unusual celebration have only recently been made public. Here’s the scoop:

At 11 a.m. Thursday, KEXP’s Cheryl Waters will broadcast a live interview with Sub Pop President Jonathan Poneman and Vice President Megan Jasper at the KEXP studio.

From noon to 5:30 p.m., KEXP DJs John Richards and Kevin Cole will broadcast live from the observation deck of the Space Needle, playing music from Sub Pop’s catalog. They will also play interview highlights with label founder Bruce Pavitt, Soundgarden’s Kim Thayil, grunge-era photographer Charles Peterson and record producer Jack Endino. will stream live performances from the Space Needle roof by singer-songwriters Sera Cahoone at 1 p.m. and J. Mascis at 3 p.m. The Mudhoney set begins at 5 p.m.

During the broadcast, the public may access the observation deck, as usual, by buying a ticket. Mudhoney and the other performers, however, will be on the roof, not in the observation-deck area with the radio-station personnel.

The Thursday event is the kickoff for Sub Pop’s Silver Jubilee, which begins Friday with a comedy benefit show at the Moore Theatre and continues Saturday with a day of free music in Georgetown.

Normally, it costs money to use the Space Needle, which is a private business. But the Sub Pop celebration involves three nonprofits — KEXP, Northwest Harvest and the Northwest Parkinson’s Foundation — so in this case the Needle “eats the costs,” said Marshall.

Paul de Barros: 206-464-3247 or