# \#optical-transients

**URL:** https://scanalyst.fourmilab.ch/tag/optical-transients/1682.md

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## [Did Three Stars Disappear within One Hour in 1952?](https://scanalyst.fourmilab.ch/t/did-three-stars-disappear-within-one-hour-in-1952/3933)

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**Author:** [@johnwalker](https://scanalyst.fourmilab.ch/u/johnwalker)\
**Replies:** 0\
**Last updated:** [2 November 2023 15:40 UTC](https://scanalyst.fourmilab.ch/t/did-three-stars-disappear-within-one-hour-in-1952/3933 "2023-11-02T15:40:10Z")

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In July 1952, photography for the Palomar Observatory Sky Survey (POSS) was underway at the 48 inch “Big Schmidt” telescope at Palomar Observatory. In a typical observing session, two 14 inch square glass …

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## [Unidentified Orbiting Objects in the 1950s?](https://scanalyst.fourmilab.ch/t/unidentified-orbiting-objects-in-the-1950s/2869)

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**Author:** [@johnwalker](https://scanalyst.fourmilab.ch/u/johnwalker)\
**Replies:** 1\
**Last updated:** [12 March 2023 15:57 UTC](https://scanalyst.fourmilab.ch/t/unidentified-orbiting-objects-in-the-1950s/2869 "2023-03-12T15:57:51Z")

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We earlier discussed the enigmatic discovery of apparent transient sources in wide-angle photographic plates exposed in the Palomar Observatory Sky Survey between 1949 and 1956 in “Objects in Geosynchronous…

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## [LaserSETI—Toward an All-Night-Sky Search for Monochromatic Transient Optical Pulses](https://scanalyst.fourmilab.ch/t/laserseti-toward-an-all-night-sky-search-for-monochromatic-transient-optical-pulses/1199)

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**Author:** [@johnwalker](https://scanalyst.fourmilab.ch/u/johnwalker)\
**Replies:** 0\
**Last updated:** [14 April 2022 12:12 UTC](https://scanalyst.fourmilab.ch/t/laserseti-toward-an-all-night-sky-search-for-monochromatic-transient-optical-pulses/1199 "2022-04-14T12:12:32Z")

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The SETI Institute’s LaserSETI project is currently observing portions of the night sky from two observatories, one in California and another on Haleakala in Hawaii. Its detectors are sensitive to short, m…