If that is what you want then hit up Palomar Mt. There is a reason there is one monster telescope up there. It would be no more than an hour from you if you take the 74e over and then hit the 15s to the 76 and go east up the Mt.
Better check road conditions.
"Division of Traffic Operations - Road Information - California Highway Information
This highway information is the latest reported as of Thursday, August 8, 2013 at 22:47 .
SR 74
[IN THE SOUTHERN CALIFORNIA AREA]
IS CLOSED FROM ANTONIO PKWY /IN SAN JUAN CAPISTRANO/ (ORANGE CO) TO
GRAND AVE /IN ELSINORE/ (RIVERSIDE CO) - DUE TO A WILD FIRE - MOTORISTS ARE
ADVISED TO USE AN ALTERNATE ROUTE
1-WAY CONTROLLED TRAFFIC AT VARIOUS LOCATIONS FROM 3.7 MI EAST TO 8.7 MI
EAST OF MOUNTAIN CENTER (RIVERSIDE CO) FROM 1900 HRS EACH NIGHT TO 0500 HRS
EACH MORNING 7 DAYS A WEEK THRU 8/22/13 - DUE TO CONSTRUCTION - MOTORISTS ARE
SUBJECT TO DELAYS OF UP TO 15 MINUTES
1-WAY CONTROLLED TRAFFIC AT VARIOUS LOCATIONS FROM PINYON DR TO
CAHUILLA WAY /IN PALM DESERT/ (RIVERSIDE CO) FROM 1900 HRS EACH NIGHT TO
0500 HRS EACH MORNING 7 DAYS A WEEK THRU 8/22/13 - DUE TO CONSTRUCTION
- MOTORISTS ARE SUBJECT TO DELAYS OF UP TO 15 MINUTES"