

Carrier Context :
Unique Projects
  La Silla: a finer view of the heavens
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The Atacama may be known for intense sunlight during the day, but radiational
cooling at night quickly lowers the outside temperature even in the summer. That's
why anyone walking around inside the actual telescope dome is usually wearing a jacket.
The cooling system is designed for the telescope, not for the astronomers,"
Silva quips. "Of course, all the astronomers work in control rooms outside the
dome, so the low temperature doesn't really matter. The control rooms are air conditioned
by Carrier, too, so the astronomers have the best of both worlds."
Using historical weather data, the dome's daytime interior temperature is based on
projections of what the exterior temperature will be that night. When the dome is
opened, Silva says, there is rarely more than a degree or two of temperature difference.
That wasn't as easy as it would seem since the distance from the dome's floor to
the ceiling is an uninterrupted 15 meters. The temperature difference between floor
and ceiling used to be seven degrees Celsius. To reduce temperature stratification,
Silva's design discharges some cool air directly under the telescope's 3.6-meter-wide
mirror at floor level; the rest of it flows up through snake-like insulated ducts
toward the dome's ceiling.
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