LOS ANGELES - It was a week into the Bobcat fire and 300-foot flames were lapping at the historic Mount Wilson Observatory.
This was the moment firefighters and observatory officials had been fearing: the fire striking a direct blow to the complex. Glowing red embers chewed through brush and trees, and thick smoke billowed into dark skies typically reserved for stargazing.
"It was gaining a flame-front we couldn't manage," said Oscar Vargas, division chief for the Angeles National Forest. "One that could destroy the observatory."
Vargas described an infernal scene of smoke and heat as he and more than 100 firefighters moved into position atop the hill to try to save the famed site.
"It was intense," he said. "We'd have to hold the lines when we could, back out when it was too hot, then jump back in with hoses and helicopters to mop the flames down and prevent the loss of structures."
The Bobcat fire's path of destruction began Sept. 6. It quickly overtook a vast swath of the Angeles National Forest, charring hundreds of thousands of acres near the foothill neighborhoods of the San Gabriel Valley and spreading all the way to the desert communities of the Antelope Valley, where dozens of structures have been damaged or destroyed.
But among the biggest worries of the blaze - now one of the largest in Los Angeles County history - has been Mount Wilson, which repeatedly has come under threat from the fire.
Considered one of the cradles of astronomy, the observatory was founded in 1904 by George Ellery Hale. When the 100-inch Hooker telescope gathered its first light on Nov. 1, 1917, it overtook its 60-inch neighbor and became the largest telescope in the world - a position it held for more than three decades.
On the night of Sept. 15, flames came within just 5 feet of the storied structure.
"It sounded like a train, or a jet engine," Vargas said of the aggressive blaze. "The way the fire was spreading through the trees and all the brush - it was like an intense sizzling, cracking and popping."