We already knew when the Flaming Lips were planning to break the Guinness World Record for most concerts in a 24-hour span -- as well as where they were scheduled to make it happen. And now, thanks to a press release issued by the band's label, we know who will be joining the band on its epic musical adventure.

Fittingly, given the band's fondness for the strange and unusual, they'll be playing host to an eclectic list of special guests, including rock legend Jackson Browne, YouTube sensations Karmin, and 'Jackass' star Chris Pontius. Also along for the ride: Neon Trees, Grace Potter & The Nocturnals, Gary Clark Jr., Hunter Hayes, GIVERS, Neon Indian, Grimes, New Fumes, and a host of other stars.

The whole thing will be broadcast via a 24-hour livestream in conjunction with the O Music Awards, the ceremony described in the press release as "a digitally driven event that celebrates and honors the artists, fans and innovators impacting digital music culture."

The band will attempt to perform eight concerts in a day, traveling around the Mississippi delta on a tour bus they've christened 'Endeavor.' You can take a look at their complete itinerary here -- and starting today (June 26), you can also purchase the Lips' 2012 Record Store Day release, 'The Flaming Lips and Heady Fwends,' at all physical and digital retailers.