Keck revisits the rings of Uranus.
I still remember the announcement, 40 years ago today.
Of course, news flowed lots slower in those days, so my eight year old self caught it days later, on one of those news shorts they would run between Saturday morning cartoons. Uranus, it turned out, has a ring system, the first planet other than Saturn known to possess such as feature. I dutifully went to the solar system chart I’d drawn in third grade, and spent the rest of the morning updating a lop-sided Uranus with a ring system all its own.
That discovery was a highlight of a mission that is largely forgotten about today; NASA’s Kuiper Airborne Observatory. Long before SOFIA finally took to the skies, there was Kuiper, the first flying infrared observatory.
We dug up a fascinating documentary short on the Kuiper to mark the occassion, complete with NASA inch-worm insignia and Van Halen-esque 70s guitars in the background:
Named after the planetary scientist Gerard Kuiper, the Kuiper Airborne Observatory sported a 36-inch mirror and operated from 1974 to 1995. Infrared astronomy was in its infancy then, as astronomers sought to get up above the moisture-laden atmosphere of the Earth that largely absorbs light at infrared wavelengths. The Wyoming Infrared Observatory telescope outside of Cheyenne was one of the first efforts to do IR astronomy from the ground, and airborne observatories such as the Kuiper and SOFIA are much more economical than satellite-based observatories like NEOWISE, and the JWST launching next year. And unlike balloon-based IR instruments, Kuiper and SOFIA offer the flexibility to tailor observing sessions.
The Kuiper observatory was built into the fuselage of a USAF C-141 Starlifter cargo aircraft. Catching the rings of Uranus during a stellar occultation stands as one of its greatest discoveries, occurring just nine years before the only flyby of Uranus to date, carried out by Voyager 2 in 1986.
Today, you can still see the Kuiper Airborne Observatory parked on the ramp at Moffett Field California, a vital piece of astronomical history.