The atmosphere is a nuisance for optical telescopes, so placing them on mountaintops where the air is thinner is a good strategy. But this winter, being above the riffraff was too much for North America’s highest astronomical observatory.
Sometime after October, no one knows exactly when, violent winds over Colorado’s Front Range blew the 15-year-old observatory’s dome to pieces.
The University of Denver’s Myer-Womble Observatory is perched at 14,148 feet near the summit of Mount Evans. “The elevation is the main thing going for it, and of course by getting above low altitude one gets above the haze layers,” said the observatory’s director and DU astronomer, Robert Stencel, “It also buys you very clear, dry, and stable air overhead at times.”
Earlier this winter, Stencel and his students looked at the building’s interior webcam and noticed unusual shadows inside. Then Stencel found some photos that winter hikers posted online. Something seemed wrong on the mountain.
In summer, visitors can take North America’s highest road to Myer-Womble, but it’s a cold and lonely place in the winter. Stencel recruited mountaineer Adam Jones, who is training to climb Everest, to check out the observatory. Jones hiked up above the weatherbeaten tree line and discovered a big hole in the observatory’s 22-foot dome.
Over four weekend visits, Jones, who is now in Nepal, slept in the shredded observatory, documented the damage and secured the observatory’s computers and binocular telescope, which appear to have escaped the wind’s wrath. He also picked up metal scraps around the building, never finding the largest missing piece.
Thanks to Jones, Stencel said the site is now stabilized and they don’t have to “go in with snowplows a-blazing” before the road opens in May.
Astronomers use Myer-Womble to educate students and the public and complement other research projects. Stencel said it might not be repaired until October, just in time for the road to close again.
Last year, Stencel and his students used Myer-Womble to observe a rare eclipsing binary star system, Epsilon Aurigae. The eclipse only comes around once every 27 years, so the past few summers were an important time for the observatory.
Stencel and his colleagues found that it’s not an ordinary second star that’s causing the eclipse, but a dark, solar system-sized disk of material. “This is the first time anyone has a picture of what’s going on,” said Stencel.
Stencel did much of the research with other space and ground-based telescopes, such as the Mount Wilson observatory in southern California, which was threatened by fires in 2009. Infrared photometry from Meyer-Womble supplemented the in-depth snapshots of Epsilon Aurigae that Stencel got from Mount Wilson. Meyer-Womble gave them as much long-term data as they wanted.
There were no weather instruments on Mount Evans this winter and past wind sensors have just blown away. Old wind gauges clocked speeds of up to 110 miles per hour on the mountain, but the sensors ice over so it could be an underestimate.
Matt Kelsch, a meteorologist at the University Center for Atmospheric Research, in Boulder, said there were five damaging storms with gusts of at least 80 miles per hour in the city this winter. Guessing which one assaulted Meyer-Womble, he picked a January storm that affected the entire east side of Colorado’s mountains and caused 95-mile-per-hour gusts at an elevation of 6,184 feet in Boulder.
Last winter was a La Nina year, when the strongest part of the jet stream tends to park over Colorado more often. When that river of air hits the Rockies from the west, it’s deflected down the slopes and windy havoc ensues.
The company that manufactured the dome is looking into wind records and trying to reconstruct when and why it failed.
“It gets into fluid dynamics and wind speed,” said Richard Olson, president of Ash Manufacturing Company, which has built thousands of otherwise sturdy observatories. “It’s a bump on the top of the mountain and it’s going to be vulnerable.”
Jet Stream Damages US Highest Astronomical Observatory