1γ = 10-5 oersted = Dynamic range of instrumentation

List of US and USSR Satellites and Probes That Have Provided Data on the Geomagnetic Field
Satellite Launch Date Inclination of Orbital Plane to Earth's equator Lifetime (days) Range (γ) Sensitivity Distance RE
Sputnik III 5-15-58 65° 30 <60,000 5% <1.3
Pioneer I 10-11-58 Earth impact 1 <1000 1% 3.7-7.0
Lunik I 1-2-59 Solar orbit 1 <6,000 200γ 3-6
Explorer VI 8-7-59 47° 61 <20,000 3% 2-7.5
Lunik II 9-12-59 Lunar impact 1.4 <1,500 50γ 3-6
Vanguard III 9-18-59 33 85 10,000-60,000 4γ <1.8
Pioneer V 3-11-60 Solar orbit 50 <1,000 0.05-5γ 5-9
Explorer X 3-25-61 33 2.2 30-5,000 3γ 1.8-7
Explorer XII 8-16-61 33 112 ±500 10γ 4-13.5
Alouette 9-29-62 80 Still operating 60,000 0.3% 1.17
Explorer XIV 10-3-62 33 300 ±250 5γ 5-16.5

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