Top Secret

Top Secret (HM21HB)

Location: Leadville, CO 80461 Lake County
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Country: United States of America
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N 39° 22.048', W 106° 11.32'

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During World War II, the Fremont Station of the Harvard College Observatory on Ceresco Ridge was strictly off-limits to mine employees.
No one knew what went on there.
But Mine Superintendent Jack Abrahms regularly left his office so Observatory Director Walt Robert could use the phone in private.
Whatever was going on, it was important.

The observatory housed a piece of equipment called a Lyot-type coronagraph, a specialized telescope used to observe solar flares.

Roberts and his staff used the coronagraph to record flare activity, which interferes with radio communications.
They coded the data, and phoned it to the Western Union office in Leadville, from where it was wired to Washington.
Military planners used the information to schedule every major operation of World War II.

The University of Colorado became involved with the operation of the observatory after the war.
It was moved to the slopes of Chalk Mountain (directly above you) to escape the town's lights.
Data collected here in the 1960's was used by NASA to help schedule manned space flights.
HM NumberHM21HB
Marker ConditionNo reports yet
Date Added Wednesday, September 6th, 2017 at 1:02pm PDT -07:00
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Locationbig map
UTM (WGS84 Datum)13S E 397604 N 4358229
Decimal Degrees39.36746667, -106.18866667
Degrees and Decimal MinutesN 39° 22.048', W 106° 11.32'
Degrees, Minutes and Seconds39° 22' 2.8799999999999" N, 106° 11' 19.2" W
Driving DirectionsGoogle Maps
Area Code(s)719, 970
Closest Postal AddressAt or near CO-91, Leadville CO 80461, US
Alternative Maps Google Maps, MapQuest, Bing Maps, Yahoo Maps, MSR Maps, OpenCycleMap, MyTopo Maps, OpenStreetMap

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