Snow falling on telescopes: Astronomy shut down on Mount Hamilton

A huge slab of ice and snow slides off the huge domed roof of the Great Refractor telescope at Mount Hamilton’s Lick Observatory and smashes thunderously to the asphalt.

“Don’t stand too close to the dome,” warns resident astronomer Elinor Gates, who has worked for 25 years at the research station atop the Bay Area’s highest peak. “That would’ve hurt.”

Mount Hamilton and Lick’s nine telescopes spread out over a half mile of ridges and peaks east of San Jose have received more than five feet of snow this winter. Historical data is incomplete, but that amount is either the largest of any winter since record keeping began in 1947 or close to it, said National Weather Service meteorologist Dalton Behringer. After the latest series of storms began delivering heavy snow on Feb. 24, more than four feet have fallen on the mountaintop. “It’s definitely unusual to have that amount in this short a time,” Behringer said.

All that snow has upended work at the University of California’s observatory, which serves as a testing ground for new optical astronomy instruments and technologies and provides crucial educational opportunities for astronomy students throughout the UC system.

Cold weather has kept much of the snow from melting. Although Lick technicians have been trudging through heavy snowdrifts and steering clear of falling ice slabs to perform vital maintenance on the delicate and expensive instruments that sit beneath the telescopes’ protective domes, astronomers have had to keep the domes shut.

The famed scientific research facility has, for now, gone blind.

“It completely disrupts our science operations,” said Gates, whose car bears the custom license plate “2650” after “Asteroid 2650 Elinor” that she discovered in the belt between Mars and Jupiter. “Snow is pretty, but when you have so much of it, it’s a real pain in the tuchus.”

A few hundred yards away, inside a cavernous dome, four space heaters provided a jury-rigged antidote to humidity and condensation that could damage the Shane telescope — the observatory’s largest, with a 10,000-pound glass mirror. A mop bucket sits near the telescope’s base. “When you get so much snow and ice on the domes, you get leaks, so we have some buckets in strategic places,” Gates said.

For telescope technician Shawn Stone, the requirement to keep all the telescopes’ cameras at an extremely low temperature — minus 166 Fahrenheit — meant multiple journeys along snow-covered roads and paths every day to refill the microwave oven-sized cooling tanks holding the image-capturing sensors. “We have to feed them a steady diet of liquid nitrogen every 12 hours,” Stone said. Staff put plastic covers on certain equipment as an added shield against intruding elements. “Our primary responsibility is to protect the telescopes,” Stone said.

After the first big snow in February, telescope technician Donnie Redel climbed 40 feet up the Shane telescope’s dome to shovel snow off the encircling catwalk. But after heavier snow fell, avalanches coming off the dome made that work unsafe. Redel, who also maintains the laser astronomers use to zap the atmosphere and create a “false star” reference point for canceling out atmospheric turbulence, typically enjoys snow. Now, he said, he’s “over it.”

The snowstorms interrupted Gates’ research into black holes in quasars, and other scientists now have holes in their data about the constantly changing behavior of exploding stars, she said. But hardest hit have been the astronomy students whose “on sky” time is severely limited by the relative scarcity of telescopes and who must finish their research by specified deadlines. Lick has been a University of California facility since its 1888 founding, and its telescopes are used by undergraduate and graduate students as well as eminent astronomers from the UC system, the Lawrence Berkeley Lab and Lawrence Livermore Lab.

Dozens of students, mostly from UC Santa Cruz and UC Berkeley, have lost precious telescope time to the snow-related closure, Gates said. Stone and Redel and other staff kept telescopes’ infrastructure operational inside the domes so students, working remotely, could at least practice basic operations and calibration to improve the odds their work would be successful when they did get “on sky,” Stone said.

The snowstorms also threw a big wrench into the daily lives of the 15 scientists and observatory staff who live in houses and apartments on site, some with their families, Gates said. Three electricity lines went down amid high winds and heavy snow, shutting off outside power for more than three days. The observatory has a facility-wide generator system, but that came under threat when authorities at the roadblock barring public access to the mountain during the storms initially refused to let the diesel truck come up to replenish the generator’s supply.

On Feb. 25, the U.S. Postal Service — despite postal workers’ motto about rain, sleet, hail and snow — couldn’t get through, even in an all-wheel-drive Subaru. “It wasn’t safe,” said mailman Faber Johnston, who delivers to the observatory from San Jose.

Lick maintenance worker Billy De Caneo, one of three staffers working with snowplows, snowblowers and shovels to clear roads, paths and driveways throughout the facility, said the snowfalls this month and last have been comparable to the big storms he lived through in Lake Tahoe before starting work at the observatory in September. “It’s been non-stop, can’t even keep up with it,” De Caneo said. “You wake up, you think it’s going to be over, another seven, eight inches the ground,” he said. “The drifts are out of this world.”

Observatory residents strapped cleats to their boots to get around on foot when whiteouts and high winds didn’t make leaving home too dangerous. After the first major dumps of snow in February, before De Caneo and other staff cleared all the roads and driveways, many of those on site were trapped for a couple of days.

Snow continued to fall on Mount Hamilton this week, with Lick receiving an inch Tuesday night. But a warm atmospheric river headed for the Bay Area was expected to douse the observatory with four to five inches of rain between Thursday morning and early Saturday, meteorologist Behringer said.

Gates said she and Lick’s other scientists and staff had worries on several fronts. The roadway could wash out, as it did once already this winter. If that happens to both the east and west, everyone at the observatory could be stuck on the mountaintop. Rain may cause “ice dams” to form on buildings and domes, diverting water inside. Snow and ice getting washed off telescope domes could hurt people and damage equipment.

“We are doing what we can to remove snow and ice from vulnerable places,” Gates said, “but with the sheer volume of snow and ice and our small staff, there is no way we can clear everything before the heavy rains start.”