Wide Field and Planetary Camera

Wide Field and Planetary Camera

WFPC image of Messier 100 (NGC 4321)
On the left, an un-corrected WFPC image of M100 in November 1993, next to an image by its replacement instrument with corrected optics

The Wide Field/Planetary Camera (WFPC) (pronounced as wiffpick) was a camera installed on the Hubble Space Telescope until December 1993. 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, though the first KH-11 KENNAN reconnaissance satellite equipped with CCDs for imaging was launched in December 1976.[1] The high sensitivity offered such promise that many astronomers strongly argued that CCDs should be considered for Hubble Space Telescope instrumentation.

This first WFPC consisted of two separate cameras, each comprising 4 800x800 pixel Texas Instruments 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.[2]

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.

On its return to Earth, the WFPC was disassembled and parts of it were used in Wide Field Camera 3,[3] which was installed in Hubble on May 14, 2009 as part of Servicing Mission 4, replacing WFPC2.

See also


  1. ^ "NRO review and redaction guide" (PDF) (2006 ed.). National Reconnaissance Office. 
  2. ^ The Space Telescope Observatory (Technical report). NASA. 1982. CP-2244. , page 28. 40 MB PDF file.
  3. ^ "WFC3 - Wide Field Camera 3". ESA. Retrieved May 12, 2009. 

External links

  • "Wide-Field Planetary Camera 2". Space Telescope Science Institute. Retrieved April 20, 2006. 
  • "Wide Field Camera 3". Space Telescope Science Institute. Retrieved April 20, 2006. 
  • "Wide Field Camera 3". NASA. Retrieved April 20, 2006. 
  • Wide-Field Planetary Camera 2 at ESA/Hubble
  • Images taken with WFPC2 at ESA/Hubble