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MegaPrime Observing Conditions Query Help


General Description

This form can be used by registered CFHTLS users to browse the catalog of MegaPrime Observing Conditions data. MegaPrime observations generate a large amount of meta-data. Some meta-data document observing conditions as measured by an array of probes at the telescope. Queries can be executed based upon time, temperature, wind, humidity and atmospheric pressure constraints.

Time Constraints

Field Name Description
Date and Time Date and time (Universal Time) of observing condition measurements.


Temperature Constraints

Field Name Description
Mirror Temperature Primary mirror temperature in celsius during observations.
Top Ring Temperature Top ring temperature in celsius during observations. Nearest location to MegaPrime.
Tower Temperature CFHT weather tower temperature in celsius during observations.


Wind Constraints

Field Name Description
Wind speed Wind speed in knots as measured by the CFHT weather tower during observations.
Wind direction Wind direction (azimuth) as measured by the CFHT weather tower during observations (N=0 E=90 S=180 W=270).


Humidity and Pressure Constraints

Field Name Description
Relative Humidity Atmospheric relative humidity in percent during observations.
Atmospheric Pressure Atmospheric pressure in kilopascals during observations.