Mars 7’s Ill-Fated Voyage, Plus One

Yesterday was a strange day … so odd that I missed posting a space history anniversary. It crossed my mind, briefly, once. I’m deeply disappointed in myself, of course.

It just so happens that forty years ago yesterday — August 9, 1973 — the USSR launched Mars 7 on a Proton K rocket from the Baikonur Cosmodrome.

(Mars 7, essentially the same as Mars 6. Image from the National Space Science Data Center.)

Launched four days after its sister ship, Mars 6, and about two weeks after a companion pair of spacecraft, Mars 4 and Mars 5, Mars 7

reached Mars on 9 March 1974. Due to a problem in the operation of one of the onboard systems (attitude control or retro-rockets) the landing probe separated prematurely (4 hours before encounter) and missed the planet by 1300 km. The early separation was probably due to a computer chip error which resulted in degradation of the systems during the trip to Mars…. The lander and bus continued on into heliocentric orbits.

While we’re on the subject of ill-fated spacecraft, and to return to the usual space history routine, 45 years ago today — August 10, 1968 — Applications Technology Satellite 4 (ATS 4) launched from Cape Canaveral atop an Atlas Centaur. The rocket’s second stage failed, however, and stranded the spacecraft in a parking orbit instead of boosting it to the planned geosynchronous orbit. Put bluntly, even though some experiments were performed, “The primary objective of inserting a gravity-gradient-stabilized spacecraft into a geosynchronous orbit was not accomplished.”

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Mars 6 Launched From Baikonur

Forty years ago today — August 5, 1973 — the Soviet Union launched their third of four 1973 missions to Mars from the Baikonur Cosmodrome on a Proton K rocket.

(Mars 6. Image from the National Space Science Data Center.)

The Mars 6 “interplanetary station” featured a descent module that separated from the spacecraft bus to enter the Martian atmosphere. The bus continued on a flyby, while transmitting back telemetry.

The first pair of the USSR’s 1973 Mars spacecraft had launched in July, and reached Mars in February 1974. Mars 6 arrived at Mars on March 12, 1974.

The descent module separated from the bus at a distance of 48,000 km from Mars. The bus continued on into a heliocentric orbit after passing within 1600 km of Mars. The descent module entered the atmosphere at 09:05:53 UT at a speed of 5.6 km/s. The parachute opened at 09:08:32 UT after the module had slowed its speed to 600 m/s by aerobraking. During this time the craft was collecting data and transmitting it directly to the bus for immediate relay to Earth. Contact with the descent module was lost at 09:11:05 UT in “direct proximity to the surface”, probably either when the retrorockets fired or when it hit the surface at an estimated 61 m/s. Mars 6 landed at 23.90 S, 19.42 W in the Margaritifer Sinus region of Mars.

Mars 6 was the first spacecraft to send back data from Mars, though its lifespan was very short as indicated above. It sent back a little under 4 minutes’ worth of data (224 seconds, to be exact).

Unfortunately, much of the data were unreadable due to a flaw in a computer chip which led to degradation of the system during its journey to Mars.

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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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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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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.

*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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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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The Spirit Rover Begins Its Martian Journey

Ten years ago today — June 10, 2003 — a Delta 2 rocket launched from Cape Canaveral carrying Mars Exploration Rover A, or “Spirit.”

(“Spirit” Mars Exploration Rover. NASA image.)

Spirit was one of two rovers designed to traverse the Martian surface to search for evidence of life, characterize the Martian climate and geology, and improve our understanding of Mars in advance of sending people to explore. Spirit’s twin, named “Opportunity,” launched a month later. Their mission’s scientific objectives were to:

1) search for and characterize a variety of rocks and soils that hold clues to past water activity,
2) determine the distribution and composition of minerals, rocks, and soils surrounding the landing sites,
3) determine what geologic processes have shaped the local terrain and influenced the chemistry,
4) perform “ground truth” of surface observations made by Mars orbiter instruments,
5) search for iron-bearing minerals, identify and quantify relative amounts of specific mineral types that contain water or were formed in water,
6) characterize the mineralogy and textures of rocks and soils and determine the processes that created them, and
7) search for geological clues to the environmental conditions that existed when liquid water was present and assess whether those environments were conducive to life.

The rovers landed successfully on Mars in January 2004. They originally were only supposed to operate for 90 Martian days (a little over 92 Earth days), but Spirit operated until March 2010 and Opportunity is still going.

In other space history …

The same day Spirit launched, Sea Launch placed the Thuraya 2 communications satellite in orbit from the Odyssey platform. Thuraya 2 is owned by the United Arab Emitrates, and provides service to the Middle East, India, etc., from geostationary orbit.*

And on this date 40 years ago, the Radio Astronomy Explorer B — also known as Explorer 49 — launched from Cape Canaveral on a Delta rocket. Its sister spacecraft, RAE-A (or Explorer 38), had been launched in July 1968. RAE-B conducted radio atronomy from an orbit around the Moon, and operated until 1977.

*Noted primarily because I like Sea Launch, having gone on one of their launch campaigns.

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Last Shuttle-Mir Flight, and Two Planetary Missions

Fifteen years ago today — June 2, 1988 — the Space Shuttle Discovery launched from Kennedy Space Center on the final Shuttle/Mir mission.

(STS-91 rolling out to the launch complex. NASA image.)

STS-91 astronauts Charles J. Precourt, Dominic L. Pudwill Gorie, Wendy B. Lawrence, Franklin R. Chang-Diaz, and Janet L. Kavandi, along with Russian cosmonaut Valery Victorovitch Ryumin, docked with the Mir space station on June 4th, marking the ninth time a shuttle had docked with the Russian station (but the first for Discovery). They transferred water and other supplies to the station, conducted a series of experiments, and returned astronaut Andrew Thomas to Earth after he spent 130 days on Mir.

In other space history …

On this date 30 years ago, the Venera 15 radar mapping spacecraft launched from the Baikonur Cosmodrome on a Proton K rocket. Its sister ship, Venera 16, launched a few days later. Venera 15 entered orbit around Venus on October 10, 1983, and operated until July 1984.

And 10 years ago today, the European Space Agency launched the Mars Express mission on a Soyuz-Fregat rocket out of Baikonur. The spacecraft arrived at Mars in December 2003 and released the “Beagle 2” lander, which unfortunately was lost. Mars Express itself continues to study the red planet from orbit.

For anyone who cares, today’s space history post was delayed because the National Space Science Data Center’s catalog of spacecraft data has been balky lately.

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Space History Double Shot: a Lost Observer and a Space Station Transfer

Twenty years ago today — September 25, 1992 — a Titan-III rocket out of Cape Canaveral launched the Mars Observer. The launch was uneventful and the spacecraft’s journey to Mars was nominal until three days before it was scheduled to enter orbit — August 21, 1993 — when controllers lost contact with the spacecraft.

(Mars Observer conceptual painting. NASA image.)

Mars Observer was primarily designed to study the Martian atmosphere, but it never got the chance, and unless we find the spacecraft someday and examine it we only have educated guesses:

It is not known whether the spacecraft was able to follow its automatic programming and go into Mars orbit or if it flew by Mars and is now in a heliocentric orbit. Later investigation concluded the most probable cause of the mishap was a fuel line rupture during fuel tank pressurization which would have caused the spacecraft to spin uncontrollably.

On a much more successful note, on this date 15 years ago — September 25, 1997 — the Space Shuttle Atlantis launched from Kennedy Space Center on a mission to the Mir space station.

STS-86 was the seventh Shuttle-Mir docking mission. Its crew consisted of U.S. astronauts James D. Wetherbee, Michael J. Bloomfield, Scott E. Parazynski, Wendy B. Lawrence, and David A. Wolf; French astronaut Jean-Loup J.M. Chrétien; and Russian cosmonaut Vladimir G. Titov. Wolf replaced Michael Foale aboard Mir, and Foale returned to Earth on Atlantis.

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