OSO 3 (Orbiting Solar Observatory 3), or Third Orbiting Solar Observatory[2][3] (known as OSO E2 before launch) was launched on March 8, 1967, into a nearly circular orbit of mean altitude 550 km, inclined at 33° to the equatorial plane. Its on-board tape recorder failed on June 28, 1968, allowing only the acquisition of sparse real-time data during station passes thereafter; the last data were received on November 10, 1969. OSO 3 reentered the Earth's atmosphere and burned up on April 4, 1982.
![]() The third Orbiting Solar Observatory, OSO 3, showing its "Sail" (upper), carrying solar experiments pointed at the Sun, and its rotating "Wheel" (lower), carrying two sky-scanning survey instruments: the UCSD hard X-ray experiment, and the MIT gamma-ray telescope | |
Mission type | Solar physics |
---|---|
Operator | NASA |
COSPAR ID | 1967-020A ![]() |
SATCAT no. | 02703![]() |
Mission duration | 2 years, 8 months |
Spacecraft properties | |
Manufacturer | BBRC |
Launch mass | 281 kilograms (619 lb) |
Start of mission | |
Launch date | March 8, 1967, 16:19:00 (1967-03-08UTC16:19Z) UTC |
Rocket | Delta C |
Launch site | Cape Canaveral LC-17A |
End of mission | |
Last contact | November 10, 1969 (1969-11-11) |
Decay date | April 4, 1982 |
Orbital parameters | |
Reference system | Geocentric |
Regime | Low Earth |
Eccentricity | 0.002164 |
Perigee altitude | 534 kilometers (332 mi) |
Apogee altitude | 564 kilometers (350 mi) |
Inclination | 32.87 degrees |
Period | 95.53 minutes |
Mean motion | 15.07 |
Epoch | May 8, 1967, 11:19:00 UTC[1] |
Like all the American Orbiting Solar Observatory (OSO) series satellites, it had two major segments: one, the "Sail", was stabilized to face the Sun, and carried both solar panels and Sun-pointing experiments for solar physics. The other, "Wheel" section, rotated to provide overall gyroscopic stability and also carried sky scanning instruments that swept the sky as the wheel turned, approximately every 2 seconds.
Name | Target | Principal Investigator |
---|---|---|
High Energy Gamma Ray (> 50 MeV) | anti-solar | Kraushaar, W. L., Massachusetts Institute of Technology |
Cosmic Ray Spectrum Detector and Gamma Ray Analyzer | Sun, all-sky | Kaplon, Morton F, University of Rochester |
Directional Radiometer Experiment | Earth | Neel, Carr B Jr, NASA Ames Research Center |
Earth Albedo (0.32- to 0.78-µm) | Earth | Neel, Carr B Jr, NASA Ames Research Center |
Solar EUV Spectrometer 0.1 to 40.0 nm | Sun | Neupert, Werner M, NASA Goddard Space Flight Center |
0.8- to 1.2-nm Solar X-Ray Ion Chamber | Sun | Teske, Richard G, University of Michigan |
Solar and Celestial Gamma-Ray Telescope (7.7 to 200 keV) | Sun, all-sky | Laurence E. Peterson University of California, San Diego |
Thermal Radiation Emissivity | near-Earth space environment | Neel, Carr B Jr, NASA Ames Research Center |
Extreme Ultraviolet Spectrometer | Sun | Hinteregger, Hans E, Phillips Laboratory |
The Sail carried a hard X-ray experiment from UCSD, with a single thin NaI(Tl) scintillation crystal plus phototube enclosed in a howitzer-shaped CsI(Tl) anti-coincidence shield. The energy resolution was 45% at 30 keV. The instrument operated from 7.7 to 210 keV with 6 channels. The Principal Investigator (PI) was Prof. Laurence E. Peterson of UCSD. Also in the wheel was a cosmic gamma-ray (>50 MeV) sky survey instrument contributed by MIT, with PI Prof. William L. Kraushaar.
OSO-3 obtained extensive hard X-ray observations of solar flares, the cosmic diffuse X-ray background, and multiple observations of Scorpius X-1, the first observation of an extrasolar X-ray source by an observatory satellite.[4][5][6][7]
The MIT gamma-ray instrument obtained the first identification of high-energy cosmic gamma rays emanating from both galactic and extra-galactic sources.[8]
The content of this article was adapted and expanded from NASA's HEASARC: Observatories OSO 3 and NASA's National Space Science Data Center: OSO 3 (Public Domain)
Solar space missions | ||
---|---|---|
Current |
| |
Past |
| |
Planned |
| |
Proposed |
| |
Cancelled |
| |
Lost |
| |
Sun-Earth | ||
|
← 1966 · Orbital launches in 1967 · 1968 → | |
---|---|
Intelsat II F-2 | OPS 1664 | IDCSP 9 · IDCSP 10 · IDCSP 11 · IDCSP 12 · IDCSP 13 · IDCSP 14 · IDCSP 15 · IDCSP 16 | Kosmos 138 | Kosmos 139 | ESSA-4 | OV3-5 | OPS 4399 | Lunar Orbiter 3 | Kosmos 140 | OPS 6073 | Diadème 1 | Kosmos 141 | Kosmos 142 | Diadème 2 | OPS 4750 | OPS 4204 | Kosmos 143 | Kosmos 144 | Kosmos 145 | OSO 3 | Kosmos 146 | Kosmos 147 | Kosmos 148 | Kosmos 149 | Kosmos 150 · OGCh No.8 | Intelsat II F-3 | Kosmos 151 | Kosmos 152 | OPS 4779 | Kosmos 153 | ATS-2 · RPM-481 | Kosmos 154 | Kosmos 155 | Unnamed | OPS 0100 | Surveyor 3 | ESSA-5 | Soyuz 1 | San Marco 2 | OPS 4243 | Kosmos 156 | OPS 6638 · OPS 6679 · ERS-18 · ERS-20 · ERS-27 | Lunar Orbiter 4 | Ariel 3 | OPS 4696 · OPS 1967 | Kosmos 157 | Kosmos 158 | Kosmos 159 | Kosmos 160 | OPS 7218 | Kosmos 161 | OPS 4321 · OPS 5557 | Explorer 34 | Molniya-1 No.8 | ESRO-2A | NRL PL-151 · NRL PL-152 · NRL PL-153 · NRL PL-154 · NRL-PL 159 · Timation 1 · Calsphere 3 · Calsphere 4 · OPS 5712 | Kosmos 162 | OPS 4360 | Kosmos 163 | Kosmos 164 | Venera 4 | Kosmos 165 | Mariner 5 | Kosmos 166 | OPS 3559 · OPS 1873 | Kosmos 167 | Zenit-4 No.32 | OPS 4286 | Unnamed | SECOR-9 · Aurora | IDCSP 16 · IDCSP 17 · IDCSP 18 · IDCSP 19 · LES-5 · DODGE | Kosmos 168 | Surveyor 4 | Kosmos 169 | Explorer 35 | Zenit-4 No.33 | OPS 1879 | OV1-11 · OV1-12 · OV1-86 | OGO-4 | Kosmos 170 | Lunar Orbiter 5 | OPS 4827 | Kosmos 171 | Kosmos 172 | OPS 4886 | OPS 7202 | Kosmos 173 | Kosmos 174 | Zenit-2 No.51 | Biosatellite 2 | Surveyor 5 | Kosmos 175 | Kosmos 176 | OPS 5089 | Kosmos 177 | Kosmos 178 | OPS 4941 | Kosmos 179 | OPS 4947 | Kosmos 180 | Unnamed | 7K-L1 No.4L | Intelsat II F-4 | Molniya-1 No.9 | OPS 1264 | Kosmos 181 | Kosmos 182 | Kosmos 183 | OSO 4 | Molniya-1 No.12 | Kosmos 184 | OPS 4995 | Kosmos 185 | Kosmos 186 | Kosmos 187 | Kosmos 188 | Kosmos 189 | OPS 0562 · OPS 1587 | Kosmos 190 | ATS-3 | Surveyor 6 | Apollo 4 | ESSA-6 | Kosmos 191 | 7K-L1 No.5L | Kosmos 192 | Kosmos 193 | WRESAT | Kosmos 194 | OV3-6 | OPS 5000 | OPS 1001 | Pioneer 8 · ERS-30 | Kosmos 195 | Kosmos 196 | Kosmos 197 | Kosmos 198 | |
Payloads are separated by bullets ( · ), launches by pipes ( | ). Crewed flights are indicated in underline. Uncatalogued launch failures are listed in italics. Payloads deployed from other spacecraft are denoted in brackets. |