Mariner 4

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Mariner 4
Mariner 4 1304 1964novembemariner4.jpg
Mission type Mars flyby
Operator NASA / JPL
COSPAR ID 1964-077A OOjs UI icon edit-ltr-progressive.svg
SATCAT no. 942
Mission duration3 years, 23 days
Spacecraft properties
Manufacturer Jet Propulsion Laboratory
Launch mass260.8 kilograms (575 lb) [1]
Power310 watts
Start of mission
Launch dateNovember 28, 1964, 14:22:01 (1964-11-28UTC14:22:01Z) UTC
Rocket Atlas LV-3 Agena-D
Launch site Cape Canaveral LC-12
End of mission
Last contactDecember 21, 1967
Orbital parameters
Reference system Heliocentric
Semi-major axis 199,591,220 kilometers (124,020,230 mi)
Eccentricity 0.17322 [2]
Perihelion altitude 166,052,670 kilometers (103,180,350 mi) [2]
Aphelion altitude 234,867,290 kilometers (145,939,770 mi) [2]
Inclination 2.544 degrees [2]
Period 567.11 days [2]
Epoch July 14, 1965, 21:00:57 UTC [2]
Flyby of Mars
Closest approachJuly 15, 1965, 01:00:57 UTC
Distance9,846 kilometers (6,118 miles)

After Mariner 3 was a total loss due to failure of the payload shroud to jettison, JPL engineers suggested that there had been a malfunction caused during separation of the metal fairing exterior from the fiberglass inner lining due to pressure differences between the inner and outer part of the shroud and that this could have caused the spring-loaded separation mechanism to become tangled and fail to detach properly. [12]

Testing at JPL confirmed this failure mode and an effort was made to develop a new, all-metal fairing. The downside of this was that the new fairing would be significantly heavier and reduce the Atlas-Agena's lift capacity. Convair and Lockheed-Martin had to make several performance enhancements to the booster to wring more power out of it. Despite fears that the work could not be completed before the 1964 Mars window closed, the new shroud was ready by November. [13]

After launch from Cape Canaveral Air Force Station Launch Complex 12, [14] the protective shroud covering Mariner 4 was jettisoned and the Agena-D/Mariner 4 combination separated from the Atlas-D booster at 14:27:23 UTC on November 28, 1964. The Agena's first burn took place from 14:28:14 to 14:30:38. The initial burn put the spacecraft into an Earth parking orbit and the second burn from 15:02:53 to 15:04:28 injected the craft into a Mars transfer orbit. Mariner 4 separated from the Agena at 15:07:09 and began cruise mode operations. The solar panels deployed and the scan platform was unlatched at 15:15:00. Sun acquisition occurred 16 minutes later. [2]

Lock on Canopus

After Sun acquisition, the Canopus star tracker went searching for Canopus. The star tracker was set to respond to any object more than one-eighth as, and less than eight times as bright as Canopus. Including Canopus, there were seven such objects visible to the sensor. It took more than a day of "star-hopping" to find Canopus, as the sensor locked on to other stars instead: [6] a stray light pattern from the near Earth, Alderamin, Regulus, Naos, and Gamma Velorum were acquired before Canopus. [3] [10]

A consistent problem that plagued the spacecraft during the early portion of its mission was that roll error signal transients would occur frequently and on occasion would cause loss of the Canopus star lock. The first attempt at a midcourse maneuver was aborted by a loss of lock shortly after the gyros began spinup. Canopus lock was lost six times within a period of less than three weeks after launch and each time a sequence of radio commands would be required to reacquire the star. After a study of the problem, the investigators concluded that the behavior was due to small dust particles that were being released from the spacecraft by some means and were drifting through the star sensor field-of-view. Sunlight scattered from the particles then appeared as illumination equivalent to that from a bright star. This would cause a roll error transient as the object passed through the field-of-view while the sensor was locked onto Canopus. When the object was bright enough that it exceeded the high gate limits at eight times the Canopus intensity, the spacecraft would automatically disacquire Canopus and initiate a roll search for a new star. Finally, a radio command was sent on December 17, 1964, that removed the high gate limit. There was no further loss of Canopus lock, although roll transients occurred 38 more times before encounter with Mars. [6] [10]

Midcourse maneuver

The 7½ month flight of Mariner 4 involved one midcourse maneuver on December 5, 1964. The maneuver was initially scheduled for December 4, but due to a loss of lock with Canopus, it was postponed. The maneuver was successfully completed on December 5; it consisted of a negative pitch turn of 39.16 degrees, a positive roll turn of 156.08 degrees, and a thrusting time of 20.07 seconds. The turns aimed the motor of the spacecraft back in the general direction of Earth, as the motor was initially pointed along the direction of flight. Both the pitch and roll changes were completed with better than 1% accuracy, the velocity change with about 2.5% accuracy. After the maneuver, Mariner 4 was on course for Mars as planned. [6]

Data transmission rate reduced

On January 5, 1965, 36 days after launch and 10,261,173 km (6,375,997 mi) from Earth, Mariner 4 reduced its rate of transmission of scientific data from 33 1/3 to 8 1/2 bits per second. This was the first autonomous action the spacecraft had taken since the midcourse maneuver. [15]

Mars flyby

The Mariner 4 spacecraft flew by Mars on July 14 and 15, 1965. Its closest approach was 9,846 km (6,118 mi) from the Martian surface at 01:00:57 UT July 15, 1965 (8:00:57 p.m. EST July 14), its distance to Earth was 216 million kilometres (134 million miles), its speed was 7 km/s (4.3 mi/s) relative to Mars, 1.7 km/s (1.1 mi/s) relative to Earth. [2]

Planetary science mode was turned on at 15:41:49 UTC on July 14. The camera sequence started at 00:18:36 UT on July 15 (7:18:49 p.m. EST on July 14) and 21 pictures using alternate red and green filters, plus 21 lines of a 22nd picture were taken. The images covered a discontinuous swath of Mars starting near 40° N, 170° E, down to about 35° S, 200° E, and then across to the terminator at 50° S, 255° E, representing about 1% of the planet's surface. The images taken during the flyby were stored in the on-board tape recorder. At 02:19:11 UTC, Mariner 4 passed behind Mars as seen from Earth and the radio signal ceased. The signal was reacquired at 03:13:04 UTC when the spacecraft reappeared. Cruise mode was then re-established. Transmission of the taped images to Earth began about 8.5 hours after signal reacquisition and continued until August 3. All images were transmitted twice to ensure no data was missing or corrupt. [2] Each individual photograph took approximately six hours to be transmitted back to Earth. [16]

The spacecraft performed all programmed activities successfully and returned useful data from launch until 22:05:07 UTC on October 1, 1965, when the long distance to Earth (309.2 million kilometres (192.1 million miles)) and the imprecise antenna orientation led to a temporary loss of communication with the spacecraft until 1967. [2]

First image hand drawn

Mariner 4 tape recorder Mariner 4 Tape Recorder.jpg
Mariner 4 tape recorder

The on-board tape recorder used on Mariner 4 was a spare, not originally intended for the Mariner 4 flight. Between the failure of Mariner 3, the fact that the Mariner 4 recorder was a spare, and some error readings suggesting an issue with the tape recorder, it was determined that the team would test the camera function definitively. This eventually led to the first digital image being painted. While waiting for the image data to be computer processed, the team used a pastel set from an art supply store to hand-color (paint-by-numbers style) a numerical printout of the raw pixels. The resulting image provided early verification that the camera was functioning. The hand-drawn image compared favorably with the final, computer-processed one. [17]

Micrometeoroid hits and end of communications

Data acquisition resumed in late 1967. The cosmic dust detector registered 17 hits in a 15-minute span on September 15, part of an apparent micrometeoroid shower that temporarily changed the spacecraft attitude and probably slightly damaged its thermal shield. Later it was speculated that Mariner 4 passed through debris of D/1895 Q1 (D/Swift) comet, and even made a flyby of that comet's possibly shattered nucleus at 20 million kilometres (12 million miles). [18] [19]

On December 7 the gas supply in the attitude control system was exhausted, and between December 10 and 11, a total of 83 micrometeoroid hits were recorded which caused perturbation of the spacecraft's attitude and degradation of the signal strength. On December 21, 1967, communications with Mariner 4 were terminated. The spacecraft is now derelict in an exterior heliocentric orbit. [20] [21]

Results

Jack N. James (center), JPL's Mariner 4 Project Manager, with a group in the White House presenting the spacecraft's famous picture Number 11 of Mars to US President Lyndon B. Johnson (center right) in July 1965 Pickering-Johnson.jpg
Jack N. James (center), JPL's Mariner 4 Project Manager, with a group in the White House presenting the spacecraft's famous picture Number 11 of Mars to US President Lyndon B. Johnson (center right) in July 1965

The total data returned by the mission was 5.2 million bits (about 634  kB). All instruments operated successfully with the exception of a part of the ionization chamber, namely the Geiger–Müller tube, which failed in February 1965. [2] In addition, the plasma probe had its performance degraded by a resistor failure on December 8, 1964, but experimenters were able to recalibrate the instrument and still interpret the data. [22] The images returned showed a Moon-like cratered terrain, [23] which scientists did not expect, although amateur astronomer Donald Cyr had predicted craters. [16] Later missions showed that the craters were not typical for Mars, but only for the more ancient region imaged by Mariner 4. A surface atmospheric pressure of 4.1 to 7.0 millibars (410 to 700 Pa) and daytime temperatures of −100 °C (−148 °F) were estimated. No magnetic field [24] [25] or Martian radiation belts [26] or, again surprisingly, surface water [16] was detected.

Bruce C. Murray used photographs from Mariner 4 to elucidate Mars' geologic history. [27]

Images of craters and measurements of a thin atmosphere [23] [28] —much thinner than expected [16] —indicating a relatively inactive planet exposed to the harshness of space, generally dissipated hopes of finding intelligent life on Mars. Life on Mars had been the subject of speculation and science fiction for centuries. [29] If there was life on Mars, after Mariner 4 most concluded it would probably be smaller, simpler forms. [4] Others concluded that a search for life on Earth at kilometer resolution, using several thousand photographs, did not reveal a sign of life on the vast majority of these photographs; thus, based on the 22 photographs taken by Mariner 4, one could not conclude there was no intelligent life on Mars. [30] The solar wind was measured, and compared with simultaneous records from Mariner 5 which went to Venus. [31]

The total cost of the Mariner 4 mission is estimated at $83.2 million (equivalent to $804 million in 2023). [2] Total research, development, launch, and support costs for the Mariner series of spacecraft (Mariners 1 through 10) was approximately $554 million (equivalent to $5.36 billion in 2023). [2]

See also

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References

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  2. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 "Mariner 4". nssdc.gsfc.nasa.gov. NASA . Retrieved May 3, 2018.
  3. 1 2 Bill Momsen (2006). "Mariner IV – First Flyby of Mars: Some personal experiences". p. 1. Archived from the original on June 20, 2002. Retrieved February 11, 2009.
  4. 1 2 Bill Momsen (2006). "Mariner IV – First Flyby of Mars: Some personal experiences". p. 2. Archived from the original on December 30, 2008. Retrieved February 11, 2009.
  5. ↑ "Mariner 4 – Mars Missions". jpl.nasa.gov. NASA . Retrieved August 30, 2022.
  6. 1 2 3 4 5 JPL Technical Memorandum No. 33-229, To Mars: The Odyssey of Mariner IV (PDF) (Report). NASA / JPL. 1965. pp. 21–23. Archived from the original (PDF) on July 3, 2007. Retrieved February 1, 2009.
  7. ↑ Hugh R. Anderson (September 10, 1965). "Initial Results, Spacecraft Description and Encounter Sequence". Science . New Series. 149 (3689): 1226–1228. Bibcode:1965Sci...149.1226A. doi:10.1126/science.149.3689.1226. PMID   17747450.
  8. ↑ Glenn A. Reiff (January 28, 1966). "Mariner IV: Developing the Scientific Experiment". Science . New Series. 151 (3709): 413–417. Bibcode:1966Sci...151..413R. doi:10.1126/science.151.3709.413. PMID   17798511.
  9. ↑ "Mariner 4: Mars TV Camera". nssdc.gsfc.nasa.gov. NASA . Retrieved April 29, 2012.
  10. 1 2 3 W. C. Goss (May 1, 1970). "The Mariner Spacecraft Star Sensors". Applied Optics. 9 (5): 1056–1067. Bibcode:1970ApOpt...9.1056G. doi:10.1364/AO.9.001056. PMID   20076329.
  11. ↑ Mariner-Venus 1967. NASA. 1971. 19720013159. Retrieved July 29, 2022.
  12. ↑ "Mariner 3 - Mars Missions". jpl.nasa.gov. NASA / JPL . Retrieved July 13, 2024.
  13. ↑ John Uri (November 26, 2019). "55 Years Ago: Mariner 4 First to Mars". nasa.gov. NASA . Retrieved August 5, 2022.
  14. ↑ Bob Granath (November 4, 2014). "MAVEN Continues Mars Exploration Begun 50 Years Ago by Mariner 4". nasa.gov. NASA . Retrieved December 19, 2015.
  15. ↑ Astronautics and Aeronautics: Chronology of Science, Technology, and Policy (PDF). NASA. 1965. SP-4006. Retrieved January 2, 2019.
  16. 1 2 3 4 Willy Lee (April 1966). "The Re-Designed Solar System". For Your Information. Galaxy Science Fiction. Vol. 24, no. 4. pp. 126–136.
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  19. ↑ Tony Phillips (August 24, 2006). "Has the Mariner Meteor Mystery Been Solved". Mars Daily. Retrieved February 11, 2009.
  20. ↑ Paul E. Filmer (January 5, 2004). "Beagle! Here Beagle, Beagle..." Retrieved February 12, 2009.
  21. ↑ Rod Pyle (2012). Destination Mars: New Explorations of the Red Planet. Prometheus Books. p. 348. ISBN   978-1-61614-589-7. It eventually joined its sibling, Mariner 3, dead ... in a large orbit around the sun.
  22. ↑ "NASA Press Release 1965-0319" (Press release). NASA / JPL. March 3, 1965. Archived from the original on October 19, 2008. Retrieved February 13, 2009.
  23. 1 2 Robert B. Leighton; Bruce C. Murray; et al. (August 6, 1965). "Mariner IV Photography of Mars: Initial Results". Science . New Series. 149 (3689): 627–630. Bibcode:1965Sci...149..627L. doi:10.1126/science.149.3684.627. PMID   17747569. S2CID   43407530.
  24. ↑ J. J. O'Gallagher; J. A. Simpson (September 10, 1965). "Search for Trapped Electrons and a Magnetic Moment at Mars by Mariner IV". Science . New Series. 149 (3689): 1233–1239. Bibcode:1965Sci...149.1233O. doi:10.1126/science.149.3689.1233. PMID   17747452. S2CID   21249845.
  25. ↑ Edward J. Smith; Leverett Davis, Jr.; et al. (September 10, 1965). "Magnetic Field Measurements Near Mars". Science . New Series. 149 (3689): 1241–1242. Bibcode:1965Sci...149.1241S. doi:10.1126/science.149.3689.1241. PMID   17747454. S2CID   43466009.
  26. ↑ J. A. Van Allen; L. A. Frank; et al. (September 10, 1965). "Absence of Martian Radiation Belts and Implications Thereof". Science . New Series. 149 (3689): 1228–1233. Bibcode:1965Sci...149.1228V. doi:10.1126/science.149.3689.1228. hdl: 2060/19650024318 . PMID   17747451. S2CID   29117648.
  27. ↑ Matt Schudel (August 30, 2013). "Bruce C. Murray, NASA space scientist, dies at 81". The Washington Post . Retrieved August 31, 2013.
  28. ↑ Arvydas Kliore; Dan L. Cain; Gerald S. Levy; et al. (September 10, 1965). "Occultation Experiment: Results of the First Direct Measurement of Mars's Atmosphere and Ionosphere". Science . New Series. 149 (3689): 1243–1248. Bibcode:1965Sci...149.1243K. doi:10.1126/science.149.3689.1243. PMID   17747455. S2CID   34369864.
  29. ↑ Frank B. Salisbury (April 6, 1962). "Martian Biology". Science . New Series. 136 (3510): 17–26. Bibcode:1962Sci...136...17S. doi:10.1126/science.136.3510.17. PMID   17779780. S2CID   39512870.
  30. ↑ Steven D. Kilston; Robert R. Drummond; Carl Sagan (1966). "A Search for Life on Earth at Kilometer Resolution". Icarus . 5 (1–6): 79–98. Bibcode:1966Icar....5...79K. doi:10.1016/0019-1035(66)90010-8.
  31. ↑ "Mariner to Mercury, Venus and Mars" (PDF). jpl.nasa.gov. Fact Sheets. NASA / JPL. May 1996. Archived from the original (PDF) on May 25, 2018. Retrieved September 2, 2014.
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