Last week there was a magnitude 5.4 earthquake northwest of Borrego Springs and east of Lake Riverside. It was only 25 miles from our house and the observatory. I was worried about the roof of the observatory jumping the rails.

During construction, there was a lot of discussion on how to protect the roof in windy conditions. We never thought about earthquakes which are probably a greater risk for a 3,000 lb roof. Nonetheless, we devised a good hold down mechanism for the roof, with steel flanges preventing any full derailment at virtually all open positions. The upshot of this protection is that we did not provide for any tie down of the roof.

Upon hearing of the earthquake, I became concerned that the shaking might derail the roof. While we had dealt with a move from the wind, I was concerned that the quake might have introduced movement we hadn’t anticipated.

All is well. As far as a nighttime inspection can find, we have no earthquake effect, let alone damage. It’s a good thing we didn’t take any lava home from Hawaii, so Pe’Lee is on our side.