Mount Wilson Fire Threat Wanes

A massive effort by thousands of firefighters on the ground and by retardant-carrying aircraft appears to have greatly lessened the threat that a massive wildfire poses to the Mount Wilson Observatory – home to two historic telescopes – officials said Wednesday.

The wildfire, known as the Station Fire, is now more than 38 percent contained after having consumed more than 144,000 acres over the last seven days, the US Forest Service said.

“Mount Wilson is still a concern, but fire personnel are feeling more comfortable that the observatory will not be damaged,” posted authorities on the Incident Information System Web site, InciWeb, Wednesday afternoon.

“The observatory grounds are in the best possible shape, the firefighters remain determined and in position, and we expect to survive this unless the approaching fire obtains far more aggressiveness and complexity than it now presents,” wrote Director Hal McAlister on the observatory’s Web site Wednesday afternoon. “I remain optimistic, but we cannot declare the end to any danger until the fire is declared contained by authorities.”

UCLA’s Towercam on the mountain, which had been providing views of the fire for interested observers, is offline due to phone line damage caused by backfires authorities set to protect the observatory site.

The observatory’s Web site was temporarily relocated to a server for the Center for High Angular Resolution Astronomy (CHARA) at Georgia State University, where McAlister teaches, after its own site went down when the phone lines were damaged. CHARA operates the CHARA Array, a six-telescope optical/infrared interferometric array atop Mount Wilson.

The field of astrophysics was founded at the 105-year-old Mount Wilson Observatory, which is home to the 100-in. Hooker telescope, named after John D. Hooker, who provided the funds for its giant mirror. It was the largest telescope in the world from 1917 to 1948, when the 200-in. telescope was built on Palomar Mountain 90 miles away. Discoveries made with the 100-in. telescope include Edwin Hubble’s landmark work on the expansion of the universe and the establishment of the cosmic distance scale. In 1919, the first optical interferometer ever used for astronomical research was used on the 100-in. telescope to measure the sizes of distant stars.

The observatory also houses the Snow solar telescope, a 60-in. telescope, a 150-ft solar telescope, and the University of California, Berkeley’s Infrared Spatial Interferometer, among other instruments. Mt. Wilson itself is also home to broadcast towers for more than 50 TV and radio stations, making it a major communications hub for Southern California.

So far, the Station Fire has burned 226 square miles within the Angeles National Forest and surrounding foothill communities. Sixty-four homes have been destroyed, and some 12,000 remain threatened. Helicopters have dropped 1.7 million gallons of water and 18,000 gallons of flame retardant, and air tankers have dropped 670,000 gallons of retardant and gel.

McAlister wrote Wednesday that he and his wife were headed to Mount Wilson today.

“Deputy Chief Powers has arranged for a fire department escort from La Canada to Red Box through all the road blocks, and we plan on staying on the mountain – in the Kapteyn Cottage – if we can,” he wrote, adding that he plans to post photos of the observatory this weekend.

For more information, visit: http://joy.chara.gsu.edu/CHARA/

See also: Fire Threatens Observatory