Yet another fire broke out in California Tuesday morning, threatening the state’s Mt. Wilson Observatory. The fire started just before 4 a.m. and continued burning in the hills above Pasadena, Arcadia and Altadena, according to KABC-TV.

The observatory was evacuated Tuesday, Robert Diaz of the Los Angeles County Fire Department confirmed to KPCC radio. Homes and other buildings in the area were not under any evacuation orders.

Firefighters said the fire could potentially reach up to 600 acres but hoped they would be able to contain it before winds and temperatures picked up throughout the day. A fire in the very same area in 2009 burned some 160,000 acres. The terrain, not the wind, was driving Tuesday’s fire, officials said. It had not yet been contained at all as of Tuesday morning.

Some 60 firefighters from the Los Angeles County Fire Department to put out the blaze, the Los Angeles Times reported. Helicopters dropped water on the area in an effort to quell the flames before they ripped through the hillside.

Mt. Wilson Observatory is home to the famed 100-inch Hooker telescope, completed in 1917. The telescope had the honor of being the world’s largest from 1917 to 1949. The observatory is celebrating the telescope’s 100th anniversary this year. But aside from the observatory’s communication towers, no homes or other buildings were threatened by Tuesday’s fire. Firefighters had not yet determined the cause of the fire. No injuries had been reported.

Flames and smoke from the Mt. Wilson fire could be seen from Los Angeles and the surrounding area. Social media users shared photos of the smoke and flames from the blaze Tuesday morning.