On April 24, 1990, a singular event occurred which revolutionized Science and Technology, and which inspired humanity. The event was the launch of the Hubble Space Telescope (HST), which entered orbit aboard the Space Shuttle Discovery (STS-31). Thirty years on, we celebrate its unique contribution to Astronomy and Planetary Sciences. Frankly spoken, this simple telescope, with a primary mirror of just 2.4 meters, has proven to be the most prolific telescope in history.
The story of the HST was never straightforward. It was burdened by long delays and, worse still, when initially tested in space, its optics were shown to be fundamentally defective and unusable for astronomical observation. Swiftly, however, and as a tremendous tribute to unparalleled international collaboration, US and international engineers proposed a brilliant and pragmatic solution. They designed and constructed an optical ‘correction’ to compensate for the underlying spherical aberration problem. Spherical aberration, is a common optical problem known to many of us who wear glasses. In the case of the HST, a new pair of ‘glasses’ was constructed on Earth and then fitted, in Space, by Shuttle Astronaut Jeffrey (“Jeff”) A. Hoffman. Jeff is well-known to us as a long-standing ISU Faculty member and MIT Professor. His background as an astrophysicist meant that he had an inherent understanding of the problem and the new ‘lens’ was fitted with immediate success.
Over the past 30 years of operation, the HST has, literally, revolutionized, all fields of astronomy, from observations of Solar System’s planets and moons, to the distant quasars, and black holes at the very center of the Milky Way galaxy. It has the nice advantage of being able to observe the cosmos at different colors (wavelengths). Drs. Hugh Hill and Bertrand Goldman of ISU’s Central Campus in Strasbourg, France, both used it for their research. Prof. Hill explains: “HST has been unique in terms of its technology, upgradability, reliability and international character. Of all these characteristics, reliability has been the most productive. HST is the standard by which all future, Space-based telescopic missions will be judged.”
“The endurance of the HST is remarkable, as it has delivered cut-edge observations for almost 30 years, thanks to the several maintenance missions and careful engineering,” according to Prof. Goldman. ”More recent space observatories are sent further away from the Earth, often to the L2 Lagrange point 1.5 million kilometers away, where they cannot be serviced but enjoy better observing conditions. However, the HST combined the high-image quality and stability above the Earth atmosphere with upgrade opportunities, which fitted perfectly the astronomical needs and technological progress of its time.”
ISU MSS17 alum Bethany Downer is the European Space Agency public information officer for Hubble. You can follow any updates via Space Telescope, Hubble Facebook page and watch Bethany’s TEDxISU on Hubble.
Even now, the ‘oversubscription rate’ of the telescope is extreme: the extent of time astronomers want to use the telescope, to the amount of time actually available is 12:1. For sure, this attests not only to scientific success but, equally, to robust international teamwork.
Picture Credit: NASA – Astronaut Jeffrey A. Hoffman, in Dec. 1993, signals directions to European Space Agency astronaut Claude Nicollier (out of frame), as the latter controls the Canadarm during the third of five spacewalks on the Hubble Space Telescope servicing mission. Astronauts Hoffman and F. Story Musgrave earlier had changed out the Wide Field\Planetary Camera (WF\PC).