The position of HSP in Hubble's instrument bay.

The High Speed Photometer (HSP) was one of the four original axial instruments on the Hubble. The HSP, which was removed from Hubble during the First Servicing Mission in December 1993, was used to make very rapid (up to 100.000 measurements pr. second) light measurements of astronomical objects at a variety of wavelengths from the near ultraviolet to the visible. It had five detectors.