Beyond_Earth-_A_Chronicle_of_Deep_Space_Exploration_1958-2016.pdf

Mariner VII

Nation: USA (46)

Objective(s): Mars flyby

Spacecraft: Mariner-69G

Spacecraft Mass: 381 kg

Mission Design and Management: NASA / JPL

Launch Vehicle: Atlas Centaur (AC-19 / Atlas 3C no. 5105C / Centaur D-1A)

Launch Date and Time: 27 March 1969 / 22:22:01 UT

Launch Site: Cape Kennedy / Launch Complex 36A

Scientific Instruments:

• 1. imaging system (two TV cameras)
• 2. infrared spectrometer
• 3. ultraviolet spectrometer
• 4. infrared radiometer
• 5. celestial mechanics experiment
• 6. S-band occultation experiment
• 7. conical radiometer

Results: Identical to Mariner VI, Mariner VII had a similar mission of flying by Mars. After Mariner VI had returned intriguing photos of Mars' south polar cap, controllers reprogrammed Mariner VII's control system to increase the number of scans of the south pole for the second spacecraft from 25 to 33. After a perfect mid-course correction on the way to Mars on 8 April 1969, on 30 July, just 7 hours before its twin was scheduled to fly by Mars, the deep space tracking station at Johannesburg, South Africa, lost contact with the spacecraft's high-gain antenna. One of two stations in Madrid, Spain was diverted from their original missions of tracking Pioneer VIII and joined the search for Mariner VII. Fortunately, the Pioneer station at Goldstone picked up faint signals from the spacecraft. Controllers sent commands to Mariner VII to switch to the low-gain antenna that worked well afterwards. Mission controllers later speculated that the spacecraft had been thrown out of alignment when struck by a micrometeoroid (although later speculations centered on the silver-zinc battery on board which might have exploded, with venting electrolytes acting like a thruster). As a result, 15 telemetry channels were lost. Despite problems with positional calibration, Mariner VII recorded 93 far-encounter and 33 near-encounter images of the planet, showing heavily cratered terrain very similar to Mariner VI. Closest approach to Mars was at 05:00:49 UT on 5 August 1969 at a distance of 3,430 kilometers. Oddly, despite the high resolution of 300 meters, Mariner VII found the center of Hellas to be devoid of craters. The spacecraft found a pressure of 3.5 millibars and a temperature of –90°F at 59° S / 28° E in the Hellespontus region, suggesting that this area was elevated about 6 kilometers above the average terrain. Post flight analysis showed that at least three photos from Mariner VII included the moon Phobos. Although surface features were not visible, the pictures clearly showed the moon to be irregularly shaped. Mariner VII entered heliocentric orbit (1.11 × 1.70 AU) and NASA maintained continued to receive data from the vehicle until mid-1971.

[Mars, M-69 no. 522]

Nation: USSR (63)

Objective(s): Mars orbit

Spacecraft: M-69 (no. 522)

Spacecraft Mass: 4,850 kg

Mission Design and Management: GSMZ imeni Lavochkina

Launch Vehicle: Proton-K + Blok D (8K82K no. 233-01 + 11S824 no. 522L)

Launch Date and Time: 2 April 1969 / 10:33:00 UT

Launch Site: NIIP-5 / Site 81/24

Scientific Instruments:

• 1. RA69 radiometer
• 2. IV1 instrument to measure water vapor levels
• 3. USZ ultraviolet spectrometer
• 4. UTV1 infrared Fourier spectrometer
• 5. KM69 cosmic ray detector
• 6. PL18M solar plasma spectrometer
• 7. RIP-803 low-energy spectrometer
• 8. GSZ gamma-ray spectrometer
• 9. UMR2M hydrogen/helium mass spectrometer
• 10. imaging system (3 cameras)
• 11. D-127 charged particle traps

Results: The second M-69 spacecraft was identical to its predecessor (launched six days before) and was intended to enter orbit around Mars on 15 September 1969. Like its twin, it also never reached intermediate Earth orbit. At launch, at T+0.02 seconds, one of the six first-stage engines of the Proton malfunctioned. Although the booster lifted off using the remaining five engines, it began veering off course and eventually turned with its nose toward the ground (at about 30° to the horizontal). At T+41 seconds, the booster impacted three kilometers from the launch site and exploded into a massive fireball. The launch complex was not affected although windows shattered in the Proton assembly building. Engineers believed that even if either or both of these M-69 Mars spacecraft had gotten off the ground, they probably had very little chance of success in their primary missions. Both the M-69 spacecraft were brought to launch in a period of immense stress and hurry for engineers at Lavochkin. In remembering the M-69 series, one leading designer, Vladimir Dolgopolov, later remembered that, "these were examples of how not to make a spacecraft."

[Luna, Ye-8-5 no. 402]

Nation: USSR (64)

Objective(s): lunar sample return

Spacecraft: Ye-8-5 (no. 402)

Spacecraft Mass: c. 5,700 kg

Mission Design and Management: GSMZ imeni Lavochkina

Launch Vehicle: Proton-K + Blok D (8K82K no. 238-01 + 11S824 no. 401L)

Launch Date and Time: 14 June 1969 / 04:00:48 UT

Launch Site: NIIP-5 / Site 81/24

Scientific Instruments:

• 1. stereo imaging system
• 2. remote arm for sample collection
• 3. radiation detector

Results: The Ye-8-5 was a variant of the basic Ye-8 lunar rover spacecraft developed by the Lavochkin design bureau. This particular version, whose development began in 1968, was designed to recover a small portion of soil from the lunar surface and return it to Earth. It shared the basic lander stage ("KT") as the rover variant (built around a structure comprising four spherical propellant tanks linked together in a square), which was now installed with a robot arm to scoop up lunar soil. The rover was replaced by a new "ascent stage" that was built around three spherical propellant tanks that consisted of a main rocket engine (the S5.61) to lift off from the Moon, a pressurized compartment for electronics, and a small 39-kilogram spherical capsule which would detach from the stage and reenter Earth's atmosphere with its valuable payload of lunar dust. On the first launch attempt of the Ye-8-5 robot scooper, the first three stages of the Proton worked without fault, but the Blok D fourth stage, which was to fire to attain orbital velocity, failed to ignite due to a disruption in the circuit of its guidance system. The payload reentered over the Pacific Ocean without reaching Earth orbit.

[N1 test flight, 7K-L1S]

Nation: USSR (65)

Objective(s): lunar orbit

Spacecraft: 7K-L1S (no. 5)

Spacecraft Mass: c. 6,900 kg

Mission Design and Management: TsKBEM

Launch Vehicle: N1 (no. 15005)

Launch Date and Time: 3 July 1969 / 20:18:32 UT

Launch Site: NIIP-5 / Site 110/38

Scientific Instruments:

[unknown]

Results: This was the second attempt to launch the giant N1 rocket. Like its predecessor, its payload consisted of a basic 7K-L1 spacecraft equipped with additional instrumentation and an attitude control block to enable operations in lunar orbit. Moments after launch, the first stage of the booster exploded in a massive inferno that engulfed the entire launch pad and damaged nearby buildings and structures for several kilometers around the area. Amazingly, the payload's launch escape system fired successfully at T+14.5 seconds and the 7K-L1 descent module was recovered safely two kilometers from the pad. An investigation commission traced the cause of the failure to the entry of a foreign object into the oxidizer pump of one of the first stage engines at T-0.25 seconds. The ensuing explosion started a fire that began to engulf the first stage. The control system shut down all engines except one by T+10.15 seconds. The booster lifted about 200 meters off the pad and then came crashing down in a massive explosion. Some estimates suggest that the resulting explosion had a power of about 25 tons of TNT.

Luna 15

Nation: USSR (66)

Objective(s): lunar sample return

Spacecraft: Ye-8-5 (no. 401)

Spacecraft Mass: 5,667 kg

Mission Design and Management: GSMZ imeni Lavochkina

Launch Vehicle: Proton-K + Blok D (8K82K no. 242-01 + 11S824 no. 402L)

Launch Date and Time: 13 July 1969 / 02:54:42 UT

Launch Site: NIIP-5 / Site 81/24

Scientific Instruments:

• 1. stereo imaging system
• 2. remote arm for sample collection
• 3. radiation detector

Results: Luna 15, launched only three days before the historic Apollo 11 mission to the Moon, was the second Soviet attempt to recover and bring lunar soil back to Earth. In a race to reach the Moon and return to Earth, the parallel missions of Luna 15 and Apollo 11 were, in some ways, the culmination of the Moon race that defined the space programs of both the United States and the Soviet Union in the 1960s. Prior to launch, due to mass constraints, designers removed one of two 1.28-kilogram radio transmitters from the Ye-8-5 ascent stage, leaving only one for the entire return part of the mission. On the way to the Moon, controllers detected abnormally high temperatures in the propellant tanks feeding the S5.61 engine (to be used for takeoff from the Moon and return to Earth). By carefully keeping the tank in the Sun's shadow, controllers were able to reduce the temperature and avoid the risk of an explosion en route. After a mid-course correction the day after launch, Luna 15 entered lunar orbit at 10:00 UT on 17 July 1969. Originally, plans were to carry out two orbital corrections, on 18 and 19 July, respectively, to put the vehicle on its landing track, but the ruggedness of the lunar terrain prompted a delay. Instead, controllers spent nearly four days studying data (over 20 communication sessions) to map out a plan of action to account for the rough geography. The two delayed corrections were eventually carried out on 19 July (at 13:08 UT) and 20 July (at 14:16 UT), putting Luna 15 into its planned 110 × 16-kilometer orbit at a retrograde inclination of 127°. Less than 6 hours after the second correction, Apollo 11 began its descent to the Moon, landing at 20:17 UT on 20 July. The original plan was for Luna 15 to embark on the Moon, less than 2 hours after Apollo 11 but it was not to be. Unsure of the terrain below, controllers delayed the landing by another 18 hours. During this critical period, Apollo 11 astronauts Neil A. Armstrong and Edwin E. "Buzz" Aldrin walked on the Moon. Finally, at 15:46:43 UT on 21 July, a little more than 2 hours prior to the Apollo 11 liftoff from the Moon, Luna 15, now on its 52nd orbit around the Moon, began its descent to the surface. Transmissions, however, abruptly ceased after four minutes instead of nearly five. According to the original plan, the main engine was to fire for 267.3 seconds and bring the vehicle down to about 2.5 kilometers altitude. During the descent, transmissions from the vehicle abruptly and suddenly ended 237 seconds into the engine firing at 15:50:40 UT. The data seemed to show that the spacecraft was 3 kilometers above the lunar surface. Later analysis indicated that Luna 15 had probably crashed onto the side of a mountain (at something like 480 kilometers/hour) as a result of incorrect attitude of the vehicle at the time of ignition of the descent engine—in other words, the spacecraft was probably descending not directly towards the surface but at a slight angle. Luna 15 crashed about 15 kilometers laterally away and 45 kilometers ahead of its assumed location. Impact was roughly at 17° N / 60° E in Mare Crisium.

Zond 7

Nation: USSR (67)

Objective(s): circumlunar flight

Spacecraft: 7K-L1 (no. 11)

Spacecraft Mass: c. 5,375 kg

Mission Design and Management: TsKBEM

Launch Vehicle: Proton-K + Blok D (8K82K no. 243-01 + 11S824 no. 18L)

Launch Date and Time: 7 August 1969 / 23:48:06 UT

Launch Site: NIIP-5 / Site 81/23

Scientific Instruments:

• 1. biological payload
• 2. radiation detectors
• 3. imaging system