Here's an exceprt from the recent question
The claim may refer to the band labeled U4 in the Celescope Catalog of Ultraviolet Stellar Observations, which refers to a filter with a spectral response centered around 1500 Angstroms and sensitive over a range from about 1200 to 1900 Angstroms. Of the four ultraviolet filters used in that catalog, U4 covered the "most extreme" ultraviolet span.
I thought that "Celescope" might be a typo but checking the link, its title is
Celescope catalog of ultraviolet stellar observations
While the report is about 250 pages long, the first line of the abstract tells us:
The catalog contains the observational results obtained by the Celescope Experiment during the first 16 months of operation of NASA's Orbiting Astronomical Observatory (OAO-2).
and there is even a Wikipedia section Orbiting Astronomical Observatory 2 - Celescope: Smithsonian Astrophysical Observatory which explains that it's an array of four telescopes equipped with UV-sensitive vidicon photocathodes. The article's link to the Uvidicon's page at the Smithsonian Museum has gone dead.
There are two questions about potentially similar UV astronomical telescopes of the same period (early 1970's) in Space Exploration SE:
- How did Skylab's electrographic ultraviolet camera work?
- How was the Moon's first telescope used? (Apollo 16)
so possibly the technology of the imaging system itself is similar.
Question(s): But I'd like to ask
How were these four telescopes used? Were they pointed as a cluster, near the same direction as the main telescope, or in four very different directions (eg. every 90°, or tetrahedrally?) Did the observatory spin, where they scanned?
How was the name "Celescope" coined exactly? Who thought it up?