Mauna Loa Solar Observatory
CHIP Telescope
(Chromospheric Helium I Imaging Photometer)


Shown on the left, the CHIP instrument being tested on the HAO roof in Boulder, Colorado. On the right, CHIP on the spar at MLSO.

A Chromospheric Helium I Imaging Photometer (CHIP) was installed with the Mk3 white light coronagraph and Digital Prominence Monitor at MLSO on 17 April 1996. CHIP was built by the HAO instrumentation group and is the first increment of the Advanced Coronal Observing System (ACOS).

CHIP is a differential device using properties of the Helium-I line at 1083 nm as an indicator of both chromospheric and coronal structures. CHIP records images of the sun at 1083 nm, as well as at a number of other nearby wavelengths (for calibration purposes). It is basically composed of a liquid crystal variable retarder Lyot filter connected to an IR CCD.

CHIP is unique compared with other Helium-I imagers, in that it obtains images every 3 minutes, the high cadence crucial to study the rapid evolution of CMEs. In addition, observations from CHIP should provide better understanding of coronal holes, coronal arcades, and the interaction between open and closed magnetic field structures.

An exciting example of a event observed with CHIP is the Disappearing Filament of September 25, 1996

Most recent CHIP data.

Calibrated CHIP data archive.

Movies of CHIP, Mk3 and DPM events.

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Last revision: 18 October 2000 - A. Stanger