First Geosynchronous Satellite

Fifty years ago today — July 26, 1963 — a Thor Delta rocket out of Cape Canaveral placed the first geosynchronous satellite in orbit.


(Syncom 2, which looked remarkably like Syncom 1. NASA image.)

Syncom 2, a follow-on to the lost Syncom 1, was geosynchronous but not geostationary: its orbital inclination was 33 degrees from the equator, which meant that its ground track formed a figure-8, the top and bottom of which were 33 degrees north and south of the equator, respectively. The satellite enabled transmission of “voice, teletype, facsimile, and data” between ground stations and ships at sea, and proved the viability of communication relay from high orbit that science fiction author Arthur C. Clarke had envisioned many years before. The Department of Defense took over operations of the satellite in January 1965.

Also on this date in space history, 5 years before Syncom 2 launched, the Explorer 4 satellite was launched from Cape Canaveral on a Jupiter C rocket. It measured charged particles (protons and electrons) in the Earth’s radiation belts, though the satellite’s unintended tumbling made the data hard to interpret and the satellite lost power after only three months.

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First Pair of a Four-Part Soviet Mission to Mars

Forty years ago this week, the Soviet Union was in the midst of launching the first two spacecraft of a four-vehicle mission to the red planet. Each was launched from the Baikonur Cosmodrome on a Proton booster.


(Mars 4. Image from the National Space Science Data Center.)

The first of the spacecraft, Mars 4, was launched on July 21, 1973 — so 40 years ago today, it was on its way. Unfortunately, it was unable to enter orbit when it got to Mars.

It was put into Earth orbit by a Proton SL-12/D-1-e booster and launched from its orbital platform roughly an hour and a half later on a Mars trajectory. A mid-course correction burn was made on 30 July 1973. It reached Mars on 10 February 1974. Due to a flaw in the computer chip which resulted in degradation of the chip during the voyage to Mars, the retro-rockets never fired to slow the craft into Mars orbit, and Mars 4 flew by the planet at a range of 2200 km. It returned one swath of pictures and some radio occultation data which constituted the first detection of the nightside ionosphere on Mars. It continued to return interplanetary data from solar orbit after the flyby.

The first of its companion spacecraft, Mars 5, was launched on July 25, 1973 — so 40 years ago today it and its Proton booster were undergoing final preparations for launch. Mars 5 successfully achieved Martian orbit, but operated for only a short time.

After a mid-course correction burn on 3 August, the spacecraft reached Mars on 12 February 1974 at 15:45 UT and was inserted into an elliptical 1755 km x 32,555 km, 24 hr, 53 min. orbit with an inclination of 35.3 degrees. Mars 5 collected data for 22 orbits until a loss of pressurization in the transmitter housing ended the mission. About 60 images were returned over a nine day period showing swaths of the area south of Valles Marineris, from 5 N, 330 W to 20 S, 130 W. Measurements by other instruments were made near periapsis along 7 adjacent arcs in this same region.

The next two missions, Mars 6 and 7, would be launched on August 5th and 9th, respectively. The loss of Mars 5 would make their operations harder, as it had been “designed to act as a communications link to the Mars 6 and 7 landers.”

Despite their ultimate failures, the series of launches themselves were quite an achievement: preparing and launching two big boosters one right after the other, and then doing it again two weeks later. One of the most interesting experiences of my Air Force career was getting to observe the initial stages — primarily mating the spacecraft to the launch vehicle — of a Proton launch campaign at Baikonur. Having seen what goes into a single launch, that they launched four payloads in such a short time is very impressive.

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First Geosynchronous Science Satellite

Thirty-five years ago today — July 14, 1978 — “the first spacecraft dedicated completely to scientific measurements in an equatorial geostationary orbit” was launched from Cape Canaveral on a Thor Delta rocket.


(A GEOS satellite in a test chamber. Image from the “Earth Observation Portal.”)

Called GEOstationary Scientific Satellite 2, it was identical to a previous version that ended up in the wrong orbit. Built by the European Space Agency and instrumented primarily to measure Earth’s magnetic field, GEOS 2 was originally a back-up satellite. Once on orbit, according to the Earth Observation Portal, GEOS 2 “provided two years of data, was placed in hibernation for eight months, then [was] revived for eight months in 1981” to support upper atmospheric studies. After those studies, it continued to operate through 1983.

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Phobos 2 — Success, Failure, and Controversy

Twenty-five years ago today — July 12, 1988 — the Soviets launched the second of two Mars orbiters atop a Proton K rocket out of the Baikonur Cosmodrome.


(Artist’s conception of Phobos. NASA image from Wikimedia Commons.)

Phobos 2 followed close on the heels of Phobos 1, which was launched a few days earlier but eventually lost power and did not reach Mars. Phobos 2, however, reached the Red Planet and operated in Martian orbit for several weeks.

Phobos 2 operated nominally throughout its cruise and Mars orbital insertion phases, gathering data on the Sun, interplanetary medium, Mars, and Phobos. Shortly before the final phase of the mission, during which the spacecraft was to approach within 50 m of Phobos’ surface and release two landers, one a mobile `hopper’, the other a stationary platform, contact with Phobos 2 was lost. The mission ended when the spacecraft signal failed to be successfully reacquired on 27 March 1989. The cause of the failure was determined to be a malfunction of the on-board computer.

The controversy surrounding the loss of Phobos 2 is that some UFO enthusiasts have conjectured that Phobos 2 did not simply fail, but was attacked by an alien spacecraft. I won’t provide links here, but if you search online you’re sure to find sites describing the incident — including images of what is supposed to be the attacking ship or the weapon itself.

I’m not sure why the Phobos mission would warrant such interference when so many subsequent missions have succeeded without incident; maybe the aliens left the scene, or are just very selective in what space probes they choose to destroy.

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Our Martian OPPORTUNITY

Ten years ago today — July 8, 2003 — the “Opportunity” rover launched from Cape Canaveral on a Delta II rocket.


(Opportunity rover. NASA image.)

Following about a month behind the “Spirit” rover, launched on June 10th, and known officially as Mars Explorer Rover-B, Opportunity was bound for the Meridiani Planum on Mars. The rover landed on January 25, 2004, to begin what was supposed to be a 90-sol (90 Martian days, very nearly 90 Earth days) mission.

Opportunity is still working today.

While contact with Spirit was lost in March 2010, Opportunity has continued to operate on the Martian surface: a tremendous tribute to the scientists and engineers who designed it, the technicians who built it, and the operators who direct it and keep its software updated. Long may it roll.

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Phobos 1

Twenty-five years ago today — July 7, 1988 — the Soviet Union launched a Proton-K from the Baikonur Cosmodrome carrying the Phobos 1 spacecraft.


(Phobos 1. Image from the National Space Science Data Center.)

Phobos 1, launched just a few days before its twin Phobos 2, was built to study the composition of its namesake Martian moon, and also to study the Martian atmosphere and surface by remote sensing from orbit. It also carried instruments to study the Sun and the interplanetary space environment.

The spacecraft operated well until an attitude system failure — caused by faulty software — oriented Phobos 1 away from the Sun and prevented its solar arrays from recharging its batteries. The failure occurred sometime between August 30 and September 2, 1988,* and as a result Phobos 1 never reached Mars.

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*As of the posting date, the NSSDC page records this failure as happening in 1989; however, other sources (e.g., this page) give the date as 1988, when the spacecraft was on the way to Mars.

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Radio Astronomy Explorer One

Fortyfive years ago today — July 4, 1968 — a Thor Delta rocket launched from Vandenberg AFB carrying the latest in NASA’s Explorer series of spacecraft.


(A technician checks Explorer 38. NASA image.)

Radio Astronomy Explorer 1, also known as Explorer 38, was designed to observe celestial radio sources — natural sources like the sun — and record the intensity of their signals over time. Despite several malfunctions, including degradation of its tape recorder, the spacecraft produced good data for scientists to examine.

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Unfortunate Japanese Mission to Mars

Fifteen years ago today — July 3, 1998 — Japan launched an M-5 rocket from the Kagoshima Space Center carrying the Nozomi spacecraft on its way to the Red Planet.


(Nozomi. Image from the National Space Science Data Center.)

Nozomi (meaning “Hope”) was originally known as “Planet B,” and was Japan’s first space probe sent to orbit Mars. It carried instruments to study the Martian atmosphere, but unfortunately a propulsion system malfunction during its swing by Earth on December 20, 1998, ultimately prevented the spacecraft from entering orbit.

To try to save the mission, operators developed a contingency plan by which Nozomi would

remain in heliocentric orbit for an additional four years, including two Earth flybys in December 2002 and June 2003, and encounter Mars at a slower relative velocity in December 2003.

However, another snag occurred in April 2002, as Nozomi was approaching another Earth flyby, when

powerful solar flares damaged the spacecraft’s onboard communications and power systems. An electrical short was caused in a power cell used to control the attitude control heating system which allowed the hydrazine fuel to freeze. The fuel thawed out as the craft approached Earth and maneuvers to put the craft on the correct trajectory for its Earth flyby were successful.

Operators guided Nozomi through the next Earth flyby in June 2003, but as the spacecraft approached Mars in December, it could not be put in the correct orientation to fire its main thruster for orbital insertion. As a result, Nozomi flew by Mars on December 14, 2003.

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First Ocean-Watching Radar Satellite

Thirty-five years ago today — June 27, 1978 — an Atlas-Agena launch vehicle out of Vandenberg AFB carried the SeaSat-1 observation satellite to orbit.


(SeaSat 1. NASA image.)

SeaSat 1, also known as the Ocean Dynamics Satellite, was “designed to provide measurements of sea-surface winds, sea-surface temperatures, wave heights, internal waves, atmospheric liquid water content, sea ice features, ocean features, ocean topography, and the marine geoid.”

SeaSat 1 was the first synthetic aperture radar satellite designed to monitor the oceans from space, but unfortunately a “massive short circuit in its electrical system” in October 1978 cut the mission short. Nevertheless, SeaSat 1 “returned a unique and extensive set of observations of the earth’s oceans” and, according to this mission page, also demonstrated “the feasibility of global satellite monitoring of oceanographic phenomena and [helped] determine the requirements for an operational ocean remote sensing satellite system.”

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First Spacehab Flight

Twenty years ago today — June 21, 1993 — the Space Shuttle Endeavour launched from the Kennedy Space Center carrying the Spacehab module for the first time.


(STS-57 astronauts took this shot of the Nile River delta and the eastern Mediterranean Sea. NASA image.)

Astronauts Ronald J. Grabe, Brian Duffy, G. David Low, Nancy J. Sherlock, Peter J. Wisoff, and Janice E. Voss spent a little over 9 days in space on mission STS-57. They conducted nearly two dozen experiments in the Spacehab, “a pressurized laboratory designed to more than double pressurized workspace for crew-tended experiments.”

In addition, the crew retrieved the European Retrievable Carrier (EURECA), which had been deployed on STS-46. The retrieval was complicated when the spacecraft’s antennas had to be manually folded during an EVA.

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