Orbiting Solar Observatory

satellite

Also known as: OSO

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Last updated

July 1, 2026

Quick Summary

The Orbiting Solar Observatory (OSO) was a series of U.S. satellites launched between 1962 and 1975. These satellites were designed to observe the Sun and its emissions, including X-rays and gamma rays from solar flares.1

Key achievements of the OSO series include:
* First observations of X-rays and gamma rays from solar flares.1
* First observation of gamma rays emitted from nuclear reactions during flares.1
* Use of an externally occulted coronagraph to view coronal mass ejections.1

These missions provided crucial data for understanding solar activity and its impact on Earth.

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space exploration
Solar and space physics
…undertaken by a series of Orbiting Solar Observatory satellites (launched 1962–75) and the astronaut crews of the Skylab space station in 1973–74, using that facility’s Apollo Telescope Mount. These were followed by the Solar Maximum Mission satellite (launched 1980). ESA developed the Ulysses mission (1990) to explore the Sun’s polar…
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…undertaken by a series of Orbiting Solar Observatory satellites (launched 1962–75) and the astronaut crews of the Skylab space station in 1973–74, using that facility’s Apollo Telescope Mount. These were followed by the Solar Maximum Mission satellite (launched 1980). ESA developed the Ulysses mission (1990) to explore the Sun’s polar…
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ultraviolet astronomy
These include eight Orbiting Solar Observatories, launched from 1962 to 1975 by the U.S. National Aeronautics and Space Administration (NASA), which enabled astronomers to obtain thousands of ultraviolet spectra of the Sun’s corona. Another series of U.S. satellites, known as Orbiting Astronomical Observatories, in service from 1968 to…
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These include eight Orbiting Solar Observatories, launched from 1962 to 1975 by the U.S. National Aeronautics and Space Administration (NASA), which enabled astronomers to obtain thousands of ultraviolet spectra of the Sun’s corona. Another series of U.S. satellites, known as Orbiting Astronomical Observatories, in service from 1968 to…
Read More