Wide Field and Planetary Camera

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^{Also can refer to 105.3 WFPC-LP}

The Wide Field/Planetary Camera (WFPC) (pronounced as wiffpick) was a camera installed on the Hubble Space Telescope. It was one of the instruments on Hubble at launch, but its functionality was severely impaired by the defects of the main mirror optics which afflicted the telescope. However, it produced uniquely valuable high resolution images of relatively bright astronomical objects, allowing for a number of discoveries to be made by HST even in its aberrated condition.

WFPC was proposed by James A. Westphal, a professor of planetary science at Caltech, and was designed, constructed, and managed by JPL. At the time it was proposed, 1976, CCDs had barely been used for astronomical imaging. However, their high sensitivity offered such promise that many astronomers strongly argued that they should be considered for Hubble Space Telescope instrumentation.

WFPC consisted of two separate cameras, each comprising 4 800X800 pixel Texas Instrument CCDs arranged to cover a contiguous field of view. The Wide Field camera had a 0.1 arcsecond pixel scale and was intended for the panoramic observations of faint sources at the cost of angular resolution. The Planetary Camera had a 0.043 arcsecond pixel scale and was intended for high-resolution observations. Selection between the two cameras was done with a four-facetted pyramid that rotated by 45 degrees.

As part of the corrective service mission (STS-61 in December 1993) the WFPC was swapped out for a replacement version. The Wide Field and Planetary Camera 2 improved on its predecessor and incorporated corrective optics needed to overcome the main mirror defect. To avoid potential confusion, the WFPC is now most commonly referred to as WFPC1.

WFPC2 was itself to be replaced by the Wide Field Camera 3 which has been under construction since 1997. It is due to be installed using the space shuttle during SM4 (service mission #4), which is now scheduled for 2008.