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Missions to Earth, in order :
(list still incomplete) plus nation, launch date, result (bold = success, red = failure, gray = inactive or destroyed)
vehicle type in parentheses if launch failure
Overall Earth geoscience success: ratio pending

  1. Explorer IV - USA 26 July 1958
    Mapped radiation from three Project ARGUS tests until 6Oct1958, beginning with 2 kilotons ship-launched from USS Norden Sound on 27Aug1958. Confirmed Christofilos theory that geomagnetic fields capture radiation and high energy particles from nuclear explosions in space. Reentered 23Oct1959.

  2. Explorer 7 - USA 13 October 1959
    Studied solar X-rays, interaction with ionosphere, composition of cosmic rays, heat emission of Earth. Tx ceased 24Aug1961.

  3. Ariel-1 (UK-4) - USA/UK 26 April 1962
    Anglo-American ionospheric satellite launched from Canaveral. Damaged by megaton-range STARFISH PRIME test @ z=400 km on 09Jul1962 even though not in LOS. Tx'd X-ray, cosmic ray data until Nov1964. Decayed 24May1976.

  4. Explorer 33 (IMP-D) - USA 01 July 1966
    Still active! geomagnetic field observatory. Discovered Luna's magnetic tail. Excessive burn prevented proper lunar orbit (Thor-Agena-Delta), in high earth/cislunar (16-day) orbit.

  5. Explorer 35 (IMP-E) - USA 19 July 1967
    Earth's magnetic tail observatory, monitors low frequency solar radio emission, micrometeoroids, solar wind, radiation. In lunar orbit (29.5-day).

  6. Interkosmos-1 - USSR/Czech/DDR 14 October 1969
    DS-U3-IK payload studied solar UV, X-ray effect on Earth upper atmosphere. Decayed 02Jan1970.

  7. Interkosmos-3 - USSR/Czech 07 August 1970
    Studied interaction between sun and Van Allen belts. Decayed 06Dec1970.

  8. Interkosmos-4 - USSR/Czech/DDR 14 October 1970
    Studied solar UV, X-ray effect on Earth ionosphere. Decayed 17Jan1971.

  9. Explorer 43 (IMP-I) - USA 13 March 1971
    9th in IMP series, studied Earth magnetosphere, decayed 23Dec1972.

  10. Shinsei - Japan 28 September 1971
    Studied cosmic rays, hf radio noise from Sun, and measured density & temperature of electrons & ions in Earth's ionosphere. In orbit.

  11. Interkosmos-5 - USSR/Czech 02 December 1971
    Studied solar activity effect on near Earth radiation field and Van Allen belts, decayed 07Apr1972.

  12. Interkosmos-7 - USSR/Czech/DDR 30 June 1972
    Studied effect of solar UV and X-rays on upper atmosphere. Decayed 05Oct1972.

  13. Aureole-2 (Oreol-2) - France/USSR 26 December 1973
    Studied energy transport from Sunto Earth. In highly inclined elliptical orbit.

  14. Interkosmos-11 - USSR/Czech/DDR 17 May 1974
    Studied effect of solar UV and X-rays on upper atmosphere. Decayed 06Sep1979.

  15. Interkosmos-16 - USSR 27 July 1976
    Studied effect of solar UV and X-rays on upper atmosphere. Decayed 10Jul1979.

  16. ISEE 1 - USA 22 October 1977
    International Sun-Earth Explorer measured interaction betwen solar wind and Earthas part of Int'l Magnetosphere Study. Decayed 26Sep1987.
    ISEE 2 - ESA 22 October 1977
    Int'l Sun-Earth Explorer. Decayed 26Sep1987.
    Although satellites had different builders, both were on same booster & destination, hence counted as one mission.

  17. Prognoz 8 - USSR 25 December 1980
    Studied interaction betwen solar wind and geomagnetosphere, in highly elliptical orbit.

  18. China-10 - PRC 19 September 1981
    Reentered 06Oct1982.
    China-11 - PRC 19 September 1981
    Reentered 17Aug1982.
    Studied effect of solar UV and X-rays on upper atmosphere, among other geoscience. Dual science payload on single launcher, counts as one mission.

  19. Aureole-3 (Oreol-3) - France/USSR 21 September 1981
    Studied Sun/Earth interaction. In highly inclined elliptical orbit.

  20. Dynamics-Explorer 1 - USA 03 August 1981
    Studied interaction of solar wind with Earth magnetosphere & upper atmosphere from highly eccentric polar orbit. Retired 28Feb1991. In high Earth orbit.
    Dynamics-Explorer 2 - USA 03 August 1981
    Decayed 19Feb1983.
    Dual science payload on single launch, counts as one mission.

  21. Prognoz 10 - USSR/Czech 26 April 1985
    (Project "Magion" or was that on Interkosmos?) Studies magnetosphere and solar wind and shock wave, in very high elliptical orbit.

  22. Interbol-1 - Russia/multinat 02 August 1995
    Geomagnetic study in conjunction with
    Magion-4. In highly elliptical cislunar orbit.

  23. Cluster I - ESA 04 June 1996 (Ariane 5)
    Cluster of four satellites to measure interaction between geomagnetic field and solar wind. Destroyed when Ariane 5 maiden flight failed to orbit. Counts as one mission.

  24. Interbol-2 - Czech/Russia/int'l 29 August 1996
    Solar wind research in conjunction with Magion-5. In highly elliptical Earth orbit.

  25. Cluster II - ESA/Russia 16 July 2000
    Cluster II - ESA/Russia 09 August 2000
    Geophysics. Constellation of four satellites in tetrahedral formation, 2000 km on a side, to measure interaction between geomagnetic field and solar wind with high precision; replacement for first mission. Counts as one mission. In highly elliptical, high Earth orbit.

  26. CHAMP - Germany July 2000
    CHAllenging Minisatellite Payload. Small gravimetric testbed.

  27. Jason 1 - USA-France 07 December 2001
    Follow-on to Topex, Jason carries Posiedon 2 ocean altimeter.
  28. TIMED - USA 07 December 2001
    TIMED is solar-terrestrial probe to study Earth's thermosphere,mesosphere & lower ionosphere, and solar & auroral energy input.
    Same launcher, but different orbits counts as two missions.

This category is rather incomplete, so the real success rate is less than 100%. Placement in this group may seem arbitrary. However, if you don't agree, by all means email me robot@ultimax.com and I might change my policy.

The dearth of Soviet/Russian missions may be due to payloads and purposes of Interkosmos, Prognoz, and especially the generic Kosmos missions not being well documented. Any further information concerning the scientific objectives of the following Kosmos missions, which have been reported to be for astronomical research, would be appreciated: Kosmos-8, -208, -230, -251, -262, -264, -307, and -461.
According to Jonathan's Space Report #458, dated 08Aug2001:

‘Koronas-F, an AUOS-SM type solar-pointing satellite built by Yuzhnoe in Dnepropetrovsk, Ukraine, carries a set of solar physics instruments.
‘There were 11 launches of earth-oriented AUOS-Z satellites between 1976 and 1991, followed by development of the two solar-pointing AUOS-SM satellites AUOS-SM-KI (Koronas-I) and AUOS-SM-KF (Koronas-F), whose names reflect the two research insitutes who were the original principal investigators for the experiment payloads. The I satellite, for the IZMIRAN geophysics institute, was launched in 1994 and reentered earlier this year. The new F satellite carries that designation because the original lead organization was the Lebedev institute known as FIAN in Russian, although it also carries experiments from IZMIRAN and other research centers. ’

Because so many Soviet astronomy payloads piggybacked on military satellites, I have decided to also include early US missions such as the Solrad series which also had covert Cold War roles.

Credit goes out to
TRW Space Log 1957-1996;
The Planetary Report published by The Planetary Society;
Proton Mission Planner's Manual;
Jonathan's Space Report; and
“Shooting Down a ‘Star’: Program 437, the US Nuclear ASAT System and Present-Day Copycat Killers” by LTC Clayton K.S. Chun, CADRE Paper #6, Air University Press, Maxwell AFB, Alabama, USA.
Visor tips to Chris Jones clj@world.std.com, Marc Rayman mrayman@jpl.nasa.gov, David Portree DSFPortree@aol.com.

Future Missions

  • GRACE - ESA-Russia November 2001 (Rokot).
    Gravity Recovery and Climate Experiment. 475 kg each. Twin high resolution gravimetric satellites.

  • Triana/TOMS - USA when?
    Map ozone, aerosols, water vapor, cloud cover, vegetation for globe from L1 point. Obtain total radiation budget for Earth.

  • Einstein Gravity Probe-B - USA September 2001.
    Determine effect of Earth on local space-time continuum by measuring tiny changes in four onboard gyroscopes. Test Theory of Relativity.

  • (proposed) GOCE - ESA-Russia 2005
    Global Ocean Circulation Experiment. High resolution gravimetric satellite to map ocean currents.

  • Storms - ESA Solar/geomagnetic observatory in 50,000 km circular equatorial earth orbit.

    More missions are planned. Let us know if we've missed any.

Asteroid News: Data from NASA's Near-Earth Asteroid Tracking System NEAT collected from the Mount Haleakala 1 meter telescope on Maui, Hawaii has been used to recalculate the number of Near Earth asteroids. The previous estimate for one km or larger asteroids in this class was between 1,000 and 2,000. The new data has significantly reduced this number to between 500 and 1,000. NASA currently has 322 near-Earth asteroids identified and hopes to have 90 percent of these asteroids identified by 2010. There are 14778 numbered Main Belt asteroids, all of whose orbits are now known. The asteroid tracking system has been on hiatus for the past year, but will be reactivated later this year using an upgraded 1.2-meter telescope. The findings appeared in the January 13 issue of the journal Nature. News courtesy of Dale Gray's Space Frontier Status Report.
What's Coming:

As promised, solar observatories and Inner System missions have been disaggregated from this list. This list will eventually be further subdivided into military, civil, and commercial missions. Presently only civil (science) missions are shown. Comprehensive list of individual instruments and capabilities (wavelength, aperture, energy, etc.) aboard each observatory. No doubt many more Soviet missions will be added to this list when their objectives clear up. Your comments are welcome: robot@ultimax.com
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These pages last updated April 1, 2003