Each of these enamel pins is one of the mission patches for a famous space mission.
The Hubble telescope has had 5 servicing missions to improve its capability. This insignia is for the second mission in 1997 that installed instruments to extend its wavelength range into the near-infrared for imaging and spectroscopy, allowing us to probe the most distant reaches of the universe and replacement of failed or degraded spacecraft components to increase efficiency and performance.
Size: approx. 3cm x 3cm