The Chicago Sinfonietta performs Gustav Holst's The Planets in Millennium Park's Pritzker Pavilion Friday at 7:30 PM. Accompanying the piece is a video of the solar system synchronized to the music, created by Adler Planetarium astronomer Jose Francisco Salgado. And from 7 to 9 PM, you can take a peek at the real thing through Adler's telescopes, which will be set up at the southeast corner of the Great Lawn (near the entrance to the BP bridge).