Fifteen Years Apart: Apollo 6 and STS-6

Forty-five years ago today — April 4, 1968 — the final qualification flight of the Saturn V launch vehicle and the Apollo spacecraft launched from the Kennedy Space Center.

(Apollo 6 launch. NASA image.)

Apollo 6 consisted of a complete three-stage Saturn V, a Command and Service Module, and a “boilerplate” or “pathfinder” Lunar Module. The mission encountered several major problems:

Two minutes and five seconds after launch, the Saturn V structure underwent a severe pogo oscillation, without damage to the spacecraft structure. Due to a manufacturing flaw and unrelated to the pogo oscillations, structural panels were lost from the lunar module adapter. Finally, after the completion of first stage firing and part way through the second stage burn, two of the five second stage J-2 engines shut down prematurely. The planned 175 km circular Earth orbit was not achieved, instead, after completion of the third stage burn, the spacecraft was in a 172.1 x 223.1 km, 89.8 min orbit. After two orbits, the third stage failed to reignite as planned, so the Service Module propulsion system was used to boost the spacecraft to an apogee of 22,225.4 km, from which the planned lunar reentry simulation took place at 36,025 km/hr, slightly less than the planned velocity of 40,000 km/hr. The Command Module splashed down 80 km off target 9 hr 50 min after launch and was recovered in good condition.

Fifteen years later, on April 4, 1983, the Space Shuttle Challenger launched from the Kennedy Space Center on its first flight, mission STS-6. Astronauts Paul J. Weitz, Karol J. Bobko, Donald H. Peterson and Story F. Musgrave spent 5 days in space and deployed the first Tracking and Data Relay Satellite.

The STS-6 mission was not without its problems. The Inertial Upper Stage placed TDRS-1 in the wrong orbit, and later the satellite’s own thrusters were used to put it into the correct orbit (much like the service module’s thrusters being used on Apollo 6, and some recent spacecraft which have been recovered by judicious use of on-board propulsion). Nevertheless, the overall STS-6 mission was successful and featured the first spacewalk from a Shuttle.

Looking back at these two launches, it seems our space exploits have regressed instead of progressed. Given 10 years between Explorer 1 and Apollo 6, and 15 years between Apollo 6 and STS-6, and 30 years since then, you might think that we should have a colony on Mars by now. So this image of Challenger rolling out in the fog seems apt:

(STS-6 rollout to pad 39A, in the fog. NASA image.)

Here’s hoping we soon catch up to the future!

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Last Saturn-Apollo Block 1 Suborbital Test Flight

Fifty years ago today — March 28, 1963 — the Saturn-Apollo 4 mission was launched from Cape Canaveral.

(Saturn SA-4. NASA image.)

Saturn-Apollo (SA) 4, or Apollo SA-4, was the final “Block 1” Saturn test, the last of four test launches of the Saturn rocket’s first stage.

The rocket was launched on a sub-orbital flight to an altitude of 129 km and a peak velocity of 5906 km/hr. After 100 seconds of flight, a pre-set timer cut off engine no. 5 as planned to test the “engine-out” capability of the booster. Fuel was successfully routed to the other seven engines and the flight continued.

Also on this date in space history, 30 years ago, the first of an advanced series of remote-sensing spacecraft, NOAA 8, launched into a polar orbit atop an Atlas E rocket out of Vandenberg AFB. Unfortunately, the satellite did not live out its two-year planned operational life: it failed in June 1984.

Finally, 10 years ago today — March 28, 2003 — Japan launched a pair of reconnaissance satellites, IGS (Information Gathering Satellite) 1A and IGS 1B, from Tanegashima Space Center on an H-2A rocket. According to the National Space Science Data Center, “One of the two spacecraft uses optical cameras with a resolution of one meter; the other uses synthetic aperture radar to provide images at a resolution of a few meters,” but it is unclear which satellite carried which sensor.

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Space History Triple Play: Apollo, Endeavour, Pioneer

First up: 45 years ago today — January 22, 1968 — a Saturn 1B launched the unmanned Apollo 5 mission from Cape Canaveral.

(Apollo 5 launch. NASA image.)

Apollo 5 was the first test flight of the Lunar Module (LM) ascent and descent stages. Once the LM was released into Earth orbit, its engines were fired in sequences that simulated a lunar approach and landing, including an abort scenario. Despite one premature shutdown of the descent propulsion system, the overall mission was considered a success.

Thirty years later — 15 years ago today — the Space Shuttle Endeavour launched from the Kennedy Space Center on mission STS-89. US astronauts Terrence W. Wilcutt, Joe F. Edwards, Jr., James F. Reilly, Michael P. Anderson, Bonnie J. Dunbar, and Andrew S.W. Thomas, along with Russian cosmonaut Salizhan S.Sharipov, docked with the Mir space station where Thomas replaced astronaut David Wolf.

Finally, on this date 10 years ago, we received the last signal from the Pioneer 10 spacecraft. On its 30-year mission (far exceeding its 21-month design life), Pioneer 10 visited Jupiter and explored the outer solar system. At the time of its last contact, the spacecraft “was 7.6 billion miles from Earth, or 82 times the nominal distance between the Sun and the Earth,” cruising in the general direction of Aldebaran.

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Three Days, Three Lunar Launches … A Few Years Apart

It seemed interesting that the anniversaries of three lunar launches fell on three consecutive days, so I’ve grouped them all in one blog post.

(Lunar Prospector. NASA image.)

The first of the three launches happened 45 years ago today — January 7, 1968 — when Surveyor 7 launched from Cape Canaveral on an Atlas Centaur rocket. The spacecraft landed on the Moon on January 9, making it the fifth of the Apollo pathfinder series to achieve a soft landing.

And 40 years ago tomorrow — January 8, 1973 — the Soviet Union launched Luna 21 from the Baikonur Cosmodrome on a Proton K rocket. Luna 21 carried and deployed Lunokhod 2, the USSR’s second lunar rover. The rover covered about 37 km during its four months of operations.

Finally, 15 years ago yesterday — January 6, 1998* — Lunar Prospector launched on an Athena 2 rocket out of Cape Canaveral. Lunar Prospector entered a low lunar polar orbit in order primarily to map the Moon’s surface for possible polar ice deposits, though it also carried instruments to study the Moon’s magnetic and gravity fields.

The mission ended on 31 July 1999 at 9:52:02 UT (5:52:02 EDT) when Lunar Prospector was deliberately targeted to impact in a permanently shadowed area of a crater near the lunar south pole. It was hoped that the impact would liberate water vapor from the suspected ice deposits in the crater and that the plume would be detectable from Earth, however, no plume was observed.

The spacecraft was sent into Shoemaker crater, and carried a portion of the remains of astronomer Eugene Shoemaker, which became a topic of discussion among the lunar colonists in my unpublished novel, Walking on the Sea of Clouds.

*It was already January 7 under Greenwich Mean Time (Universal Time).

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The Final — No, the Most Recent — Lunar Mission

Forty years ago today — December 7, 1972 — Apollo 17 lifted off aboard a Saturn V rocket out of Cape Canaveral as the last Apollo lunar mission.

(Gene Cernan, the most recent man to walk on the Moon. NASA image.)

Astronauts Eugene A. Cernan, Ronald E. Evans, and Harrison H. Schmitt comprised the Apollo 17 crew. On their first day in space, the crew took the iconic “Blue Marble” photograph with a hand-held Hasselblad camera.

Cernan and Schmitt landed the Lunar Module “Challenger” in the Taurus-Littrow region of the Moon on December 11. Evans stayed in lunar orbit aboard the Command and Service Module “America.”

Apollo 17 focused on surveying surface features and sampling geological materials in a region selected because it would yield both older and younger samples than previous Apollo missions, and featured Schmitt as the first scientist to land on the Moon. Schmitt and Cernan drove the lunar rover a total of 30.5 kilometers during their 75-hour stay on the Moon, and collected 110.4 kilograms (243 pounds) of lunar material.

When Cernan climbed aboard the Lunar Module to depart the moon, he said, “We leave as we came and God willing as we shall return, with peace and hope for all mankind.”* Usually he is referred to as the last man to walk on the Moon, but I prefer to think of him as the most recent man to walk on the Moon.

And even though I won’t get to be the next person to walk on the Moon, I hope someday to see another person walk on the Moon, and Mars, and even other worlds.

*Shameless plug: I made that sentiment a key part of my short story, “Memorial at Copernicus.”

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Project High Water II

Fifty years ago today — November 16, 1962 — another pre-Apollo test flight of the Saturn-1 launch vehicle was made from Cape Canaveral.

(SA-3 on the launch pad. NASA image.)

Dubbed SA-3, this mission was the first to be flown with the Saturn first stage fully-fueled. The upper stages carred 23,000 gallons of water which would be released in the “Project High Water II” cloud experiment.

When the vehicle reached the zenith of its sub-orbital flight, the upper stage was detonated to release the water. The resulting cloud of ice particles was intended to shed light on the physics of the upper atmosphere, but the telemetry was not good enough to produce reliable data.

Aside from the poor data from the “High Water” experiment, however, the main objectives for the flight test itself were all met.

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Space History Today: First Successful Saturn V Launch

Forty-five years ago today — November 9, 1967 — NASA launched the unmanned Apollo 4 mission from the Kennedy Space Center.

(Apollo 4 launch. NASA image.)

Also known as Apollo-Saturn 501, Apollo 4 was the first test flight of the complete Saturn V rocket, carrying a full-up Command and Service Module. The mission was designed to test

  • launch vehicle and spacecraft compatibility
  • the vehicle’s structural integrity under launch loads
  • heat shield and thermal systems
  • stage separation and reentry operations
  • and other factors, including mission support facilities and operations

It wouldn’t be long after Apollo 4 before crews were launching on operational Apollo missions.

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Surveyor 5: Pathfinder for Apollo 11

Forty-five years ago today — September 8, 1967 — an Atlas Centaur launch vehicle carried the Surveyor 5 lander out of Cape Canaveral on its way to the moon.

(Surveyor and Apollo landing sites. Note the close proximity of Surveyor 5 (S5) and Apollo 11. NOAA image.)

Surveyor 5 landed on the moon on September 11, 1967, but not until mission controllers overcame a hardware problem. After the midcourse correction

the spacecraft began losing helium pressure. It was concluded that the helium pressure valve had not reseated tightly and the helium was leaking into the propellant tanks, causing an overpressure which opened the relief valves, discharging the helium. A new emergency landing plan was adopted. Early vernier engine firings were made while there was still helium to slow the spacecraft, reduce its mass, and leave more free volume in the propellant tanks for the helium. The burn of the main retrorocket was delayed [to] an altitude of 1300 meters at a velocity of 30 m/s rather than the planned 10,700 meters at 120 to 150 m/s.

Surveyor 5 landed in the southwest area of Mare Tranquillitatis — the Sea of Tranquility. Two years later, Neil Armstrong and Buzz Aldrin would land Apollo 11 about 30 km away from Surveyor 5’s landing site.

The Surveyor 5 spacecraft operated on the lunar surface for 4 lunar days — shutting down during each 2-week-long lunar night — and sent its final transmission on December 17, 1967.

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Farewell, Neil Armstrong

Neil Armstrong, first human to walk on the moon, has taken his final small step, his final giant leap into the great unknown.

Other people with deeper insight will pen better tributes than I. All I can contribute is a measure of how much of an inspiration Armstrong and his astronaut colleagues have been to me: in my decision to join the Air Force and to work specifically in space and missiles, and in my desire to explore space in my imagination and my stories.

Thank you, Neil Armstrong, and Godspeed.


Previous Armstrong-related space history posts:
Apollo 11’s 40th Anniversary
Happy Birthday, Neil Armstrong

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Last of the Pre-Apollo Lunar Orbiters

Forty-five years ago today — August 1, 1967 — Lunar Orbiter 5 was launched by an Atlas Agena from Cape Canaveral.

(Lunar Orbiter 5. NASA image.)

As noted, Lunar Orbiter 5 was the last of the series, “designed to to take additional Apollo and Surveyor landing site photography and to take broad survey images of unphotographed parts of the Moon’s far side.”

The spacecraft acquired photographic data from August 6 to 18, 1967, and readout occurred until August 27, 1967. A total of 633 high resolution and 211 medium resolution frames at resolution down to 2 meters were acquired, bringing the cumulative photographic coverage by the 5 Lunar Orbiters to 99% of the Moon’s surface.

Mission Control commanded Lunar Orbiter 5 to de-orbit and hit the lunar surface five months after its photography mission was completed.

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