Earth and Space News: Comet Kohoutek perihelion December 1973

Showing posts with label Comet Kohoutek perihelion December 1973. Show all posts

Wednesday, December 30, 2020

Edward Gibson Sketched Comet Kohoutek After Third Skylab 4 EVA Dec. 29

Summary: Edward Gibson sketched Comet Kohoutek after the third Skylab 4 EVA Dec. 29, 1973, one day after perihelion, the closest comet-to-sun distance.

Comet Kohoutek’s appearance on Saturday, Dec. 29, 1973, one day after perihelion, by Skylab 4 scientist pilot Edward Gibson; post-flight, color sketch, based on black-and-white sketch drawn after third Skylab 4 EVA, conducted Dec. 29; G. Gary, Comet Kohoutek (1974), Figure 2, page 5: Public Domain, via Internet Archive

Edward Gibson sketched Comet Kohoutek after the third Skylab 4 EVA Dec. 29, 1973, the day after the recently discovered comet’s Friday, Dec. 28, reach of perihelion (Ancient Greek: περί, perí, “near” + ἥλιος, hḗlios, “sun”), its closest distance to the sun.

The Skylab 4 mission was scheduled to maximize observations of Comet Kohoutek, discovered Wednesday, March 7, 1973, at northern Germany’s Hamburg Observatory (Hamburger Sternwarte) by Czech astronomer Luboš Kohoutek (born Jan. 29, 1935). The mission’s Friday, Nov. 16, 1973, launch and Friday, Feb. 8, 1974, splashdown largely overlapped with Comet Kohoutek’s perihelion passage between December 1973 and January 1974.

Skylab 4 numbered as the National Aeronautics and Space Administration’s (NASA) third and final manned mission to Skylab, the first United States space station. All three Skylab 4 astronauts were rookies, with no previous spaceflight experience. The crew comprised Gerald Paul Carr (born Aug. 22, 1932) as commander, Edward George Gibson (born Nov. 8, 1936) as scientist pilot and William Reid Pogue (Jan. 23, 1930-March 3, 2014) as mission pilot.

Four days elapsed between the start times of the mission’s second and third EVAs. Skylab 4’s second EVA began Christmas Day, Tuesday, Dec. 25, 1973, at 16:00 Coordinated Universal Time (11 a.m. Eastern Standard Time). The mission’s third EVA (extravehicular activity) began Saturday, Dec. 29, 1973, at 17:00 UTC (12 p.m. EST).

The lapse between the second EVA’s end and the third EVA’s start, however, amounted to one minute short of 3 days 18 hours. EVA2 lasted longer than anticipated, with an actual, record-breaking duration of 7 hours 1 minute.

EVA 3 required only 3 hours 29 minutes. The mission’s third EVA ended at 20:29 UTC (3:29 p.m. EST).

Commander Carr and scientist pilot Gibson participated in the third Skylab 4 EVA. EVA 3 counted as the second career spacewalk for both of them. Gibson had joined William Pogue in the mission’s first EVA, which began Thanksgiving Day, Thursday, Nov. 22, at 17:42 UTC (12 p.m. EST), and ended 6 hours 33 minutes later, Friday, Nov. 23, at 00:15 UTC (Thursday, Nov. 22, at 7:15 p.m. EST). Carr had partnered with Pogue Christmas Day for his first spacewalk, which was Pogue’s second.

Both EVA 2 and EVA 3 emphasized photography of Comet Kohoutek with the mission’s far-ultraviolet electrographic camera. Originally designed as a backup model for the Apollo 16 mission’s S201 lunar surface experiment in late April 1972, the camera was modified for inside and outside imaging of Comet Kohoutek.

After the completion of EVA 3, Gibson continued his free time practice of making sketches of his visual observations of Comet Kohoutek. Gibson’s drawing of his Dec. 29 view of the comet numbered as his second sketch. He based his drawing on observations outdoors during EVA 3 and indoors at window number three in the Structural Transition Section (STS) linking the station's Multiple Docking Adaptor (MDA) and Airlock Module (AM).

Gibson’s first sketch dated to Tuesday, Dec. 18, 10 days before perihelion. He made a total of 10 sketches between December 1973 and January 1974. His last sketch presented the comet’s appearance Sunday, Jan. 6, nine days after Comet Kohoutek’s perihelion.

In a paper presented at the Comet Kohoutek Workshop of June 13-14, 1974, at Marshall Space Flight Center (MSFC) in Huntsville, Alabama, Gibson explained that his sketches “. . . were not in the pre-mission plans and were drawn when the crew could find free time” (page 3). His strategy for depicting the comet relied upon 10-power binoculars for most observations. Commander Carr and Pilot Pogue then reviewed Gibson’s drawings “. . . to ensure that the sketches were consistent with their observations.” He noted that after the mission he drew another set in color “. . . corresponding to each of the in-flight sketches” (page 3).

The takeaways for Edward Gibson’s sketch of Comet Kohoutek after the third Skylab 4 EVA Saturday, Dec. 29, 1973, are that the black-and-white drawing reflects the crew’s collective impression of the recently discovered comet’s appearance one day after perihelion, that he made a total of 10 black-and-white sketches onboard Skylab and that, after his return to Earth, he made corresponding sketches in color.

sketch of Comet Kohoutek, drawn by Edward Gibson after third Skylab 4 EVA, Saturday, Dec. 29, 1973, one day after the comet’s reach of perihelion: C.A. Lundquist, Skylab’s Astronomy and Space Sciences (1979), Figures 4-18, pages 54: "Work of the US Gov. Public Use Permitted," via NASA History

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

Gary, Gilmer Allen, ed. Comet Kohoutek: A Workshop Held at Marshall Space Flight Center Huntsville, Alabama June 13-14, 1974. Washington DC: National Aeronautics and Space Administration, 1975.
Available via Internet Archive @ https://archive.org/details/CometKohoutek

George C. Marshall Space Flight Center. MSFC Skylab Kohoutek Project Report. NASA Technical Memorandum TM X-64880. Huntsville AL: October 1974.
Available via Internet Archive @ https://archive.org/details/NASA_NTRS_Archive_19740027130
Available via NASA Technical Reports Server (NASA NTRS) @ https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19740027130.pdf

Gibson, Edward G. “Skylab Visual Observation of Comet Kohoutek.” Pages 3-14. In: Gilmer Allen Gary, ed. Comet Kohoutek: A Workshop Held at Marshall Space Flight Center Huntsville, Alabama June 13-14, 1974. Washington DC: National Aeronautics and Space Administration, 1975.
Available @ https://archive.org/details/CometKohoutek/page/n13

Hitt, David; Owen Garriott; and Joe Kerwin. Homesteading Space: The Skylab Story. Featuring the In-Flight Diary of Alan Bean. Lincoln NE: University of Nebraska Press, 2008.
Available via Google Books @ https://books.google.com/books/about/Homesteading_Space.html?id=sR5Cm_zeIekC

Lundquist, Charles A., ed. “Chapter 4: Observations of Comet Kohoutek.” Skylab’s Astronomy and Space Sciences: 42-63. NASA SP-404. Washington DC: National Aeronautics and Space Administration Scientific and Technical Information Office, 1979.
Available @ https://history.nasa.gov/SP-404/ch4.htm

Marriner, Derdriu. “Arabella and Anita Spun First Space Webs in August 1973 at Skylab.” Earth and Space News. Wednesday, July 31, 2013.
Available @ https://earth-and-space-news.blogspot.com/2013/07/arabella-and-anita-spun-first-space.html

Marriner, Derdriu. "Edward Gibson Sketched Comet Kohoutek’s Changes During Close Approach." Earth and Space News. Wednesday, Jan. 15, 2020.
Available @ https://earth-and-space-news.blogspot.com/2020/01/edward-gibson-sketched-comet-kohouteks.html

Marriner, Derdriu. “First Space Spiders Arabella and Anita Spun Very Fine Webs for Skylab.” Earth and Space News. Wednesday, Sept. 2, 2020.
Available @ https://earth-and-space-news.blogspot.com/2020/09/first-space-spiders-arabella-and-anita.html

Marriner, Derdriu. “First Web in Space Was Spun in 1973 by Common Cross Spider Arabella.” Earth and Space News. Wednesday, Aug. 5, 2020.
Available @ https://earth-and-space-news.blogspot.com/2020/08/first-web-in-space-was-spun-in-1973-by.html

Marriner, Derdriu. “Fourth Moonwalker Alan Bean Commanded Skylab 3 July to September 1973.” Earth and Space News. Wednesday, July 22, 2020.
Available @ https://earth-and-space-news.blogspot.com/2020/07/fourth-moonwalker-alan-bean-commanded.html

Marriner, Derdriu. “Owen Garriott and Jack Lousma Did Second EVA Aug. 24, 1973, at Skylab.” Earth and Space News. Wednesday, Aug. 19, 2020.
Available @ https://earth-and-space-news.blogspot.com/2020/08/owen-garriott-and-jack-lousma-did.html

Marriner, Derdriu. “Skylab 3 Astronaut Wives Pranked Spouses With Unofficial Mission Patch.” Earth and Space News. Wednesday, July 15, 2020.
Available @ https://earth-and-space-news.blogspot.com/2020/07/skylab-3-astronaut-wives-pranked.html

Marriner, Derdriu. “Skylab 3 Captured Dramatic Solar Prominences in August 1973.” Earth and Space News. Wednesday, Aug. 26, 2020.
Available @ https://earth-and-space-news.blogspot.com/2020/08/skylab-3-captured-dramatic-solar.html

Marriner, Derdriu. “Skylab 3 Mission Patch Emphasized Earth, Sun and Medical Themes.” Earth and Space News. Wednesday, July 8, 2020.
Available @ https://earth-and-space-news.blogspot.com/2020/07/skylab-3-mission-patch-emphasized-earth.html

Marriner, Derdriu. “Skylab 4 Imaged Comet Kohoutek During Second EVA on Christmas Day 1973.” Earth and Space News. Wednesday, Dec. 23, 2020.
Available @ https://earth-and-space-news.blogspot.com/2020/12/skylab-4-imaged-comet-kohoutek-during.html

Marriner, Derdriu. “Skylab 4 Imaged Comet Kohoutek’s Hydrogen Halo November 1973 to February 1974.” Earth and Space News. Wednesday, Dec. 16, 2020.
Available @ https://earth-and-space-news.blogspot.com/2020/12/skylab-4-imaged-comet-kohouteks.html

Marriner, Derdriu. “Skylab 4 Mission Began Observing Comet Kohoutek in November 1973.” Earth and Space News. Wednesday, Nov. 11, 2020.
Available @ https://earth-and-space-news.blogspot.com/2020/11/skylab-4-began-observing-comet-kohoutek.html

Marriner, Derdriu. “Skylabbers Owen Garriott and Jack Lousma First Spacewalked Aug. 6, 1973.” Earth and Space News. Wednesday, Aug. 12, 2020.
Available @ https://earth-and-space-news.blogspot.com/2020/08/skylabbers-owen-garriott-and-jack.html

Marriner, Derdriu. “Space Spider Anita Died Sept. 16, 1973, During Skylab 3 Mission.” Earth and Space News. Wednesday, Sept. 9, 2020.
Available @ https://earth-and-space-news.blogspot.com/2020/09/space-spider-anita-died-sept-16-1973.html

Marriner, Derdriu. “Space Spider Arabella Logged 24 Million Miles in 858 Orbits via Skylab.” Earth and Space News. Wednesday, Sept. 23, 2020.
Available @ https://earth-and-space-news.blogspot.com/2020/09/space-spider-arabella-logged-24-million.html

Marriner, Derdriu. “Two Mummichog Minnows Became First Fish in Space in 1973 Via Skylab 3.” Earth and Space News. Wednesday, July 29, 2020.
Available @ https://earth-and-space-news.blogspot.com/2020/07/two-mummichog-minnows-became-first-fish.html

Shayler, David J.; and Colin Burgess. NASA’s Scientist-Astronauts. Springer-Praxis Books in Space Exploration. Chichester UK: Praxis Publishing Limited, 2007.

Wednesday, December 23, 2020

Skylab 4 Imaged Comet Kohoutek During Second EVA on Christmas Day 1973

Summary: Skylab 4 imaged Comet Kohoutek during second EVA on Christmas Day, Dec. 25, 1973, three days before perihelion, the closest comet-to-sun distance.

Comet Kohoutek, at three days’ distance from perihelion; false-color reproduction of black-and-white photograph taken during Christmas Day spacewalk, Dec. 25, 1973, by Skylab 4 mission pilot William Pogue, with far-ultraviolet electrographic camera; yellow (center) is brightest area, with outward color successions indicating decreasing brightness; C.A. Lundquist, Skylab’s Astronomy and Space Sciences (1979), Figure 4-1: "Work of the US Gov. Public Use Permitted," via NASA History

Skylab 4 imaged Comet Kohoutek during the second EVA, on Christmas Day, Dec. 25, 1973, three days before the recently discovered comet reached perihelion (Ancient Greek: περί, perí, “near” + ἥλιος, hḗlios, “sun”), its closest distance to the sun.

Czech astronomer Luboš Kohoutek (born Jan. 29, 1935) discovered his namesake comet via plates obtained Wednesday, March 7, 1973, at northern Germany’s Hamburg Observatory (Hamburger Sternwarte). The long-period comet was calculated to makes its perihelion (Ancient Greek: περί, perí, “near” + ἥλιος, hḗlios, “sun”) passage between December 1973 and January 1974 and to reach perihelion on Friday, Dec. 28, 1973.

Skylab 4 launched Friday, Nov. 16, 1973, from east central Florida’s John F. Kennedy Space Center as the National Aeronautics and Space Administration’s (NASA) third and last manned mission to Skylab, the first United States space station. Skylab had been launched into low Earth orbit six months earlier, on May 14, 1973, from Kennedy Space Center.

The three-astronaut crew of Skylab 4 made their first, and only, spaceflights via the mission. The mission’s commander was Gerald Paul Carr (born Aug. 22, 1932). Edward George Gibson (born Nov. 8, 1936) and William Reid Pogue (Jan. 23, 1930-March 3, 2014) served as the mission’s scientist pilot and pilot, respectively.

Carr and Pogue’s EVA (extravehicular activity) on Tuesday, Dec. 25, 1973, marked NASA’s first Christmas Day spacewalk and numbered as the mission’s second spacewalk. Gibson and Pogue had conducted Skylab 4 mission’s first EVA Thursday, Nov. 22, 1973, as NASA’s first Thanksgiving Day spacewalk.

EVA 2 began at 16:00 Coordinated Universal Time (11 a.m. Eastern Standard Time) and ended at 23:01 UTC (6:01 p.m. EST). Repairs and an unplanned issue with the station’s proper attitude prolonged the spacewalk from its originally scheduled length of 3 hours 50 minutes to its actual duration of 7 hours 01 minute. The record-breaking spacewalk’s length remained unsurpassed until the Aug. 31, 1985, EVA 1 of 7 hours 20 minutes conducted by James Dougal Adrianus “Ox” van Hoften (born June 11, 1944) and William Frederick Fisher (born April 1, 1946) during Space Shuttle Discovery’s sixth flight.

While Carr attended to the stuck filter wheel on the Apollo Telescope Mount’s (ATM) S056 X-ray Telescope, Pogue photographed Comet Kohoutek for the mission’s S201 experiment. Principal investigator Thornton Page designed the S201 experiment for studying Comet Kohoutek’s coma, or gaseous halo formed around the nucleus, in the far ultraviolet spectrum of electromagnetic radiation. Page had arranged for use and modification of one of the backup far-ultraviolet electrographic cameras designed by his U.S. Naval Research Laboratory (NRL) colleague, George Robert Carruthers (born Oct. 1, 1939), for the Apollo 16 mission (Sunday, April 16, to Thursday, April 27, 1972).

In an interview July 17, 2000, with NASA Johnson Space Center (JSC) historian Kevin M. Rusnak, Pogue recalled his outdoor photographs of Comet Kohoutek at three days’ distance from perihelion. “As a matter of fact, I took this instrument outside to take pictures and images of the comet,” Pogue related. “It was kind of tricky because I had to use one of the solar panels off of the ATM to shield the sun, because it was so close to the sun, it’s approaching the sun. So I finally got this thing into position and kind of eyeballed it so that the solar panel would be shading the sun” (pages 12-43 to 12-44).

The takeaways for Skylab 4’s images of Comet Kohoutek during the mission’s second EVA on Christmas Day 1973 are that the images capture the recently discovered comet at three days’ distance from perihelion and that over 11 years 8 months passed before Skylab 4’s record EVA length of 7 hours 1 minute was finally surpassed during Space Shuttle Discovery’s sixth flight.

(left) Figure 4-13: far-ultraviolet electrographic camera capture of Comet Kohoutek (white arrow; upper right) and stars, filtered for wavelengths from 125 to 160 nanometers (nm); Tuesday, Dec. 25, 1973; (right) Figure 4-14: false-color enhancement of Comet Kohoutek and stars from Figure 4-13 to reveal ranges of optical density (sky’s “brightness”) via corresponding color zones: C.A. Lundquist, Skylab’s Astronomy and Space Sciences (1979), Figures 4-13 to 4-14, pages 51-52: "Work of the US Gov. Public Use Permitted," via NASA History

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

Belew, Leland F. "Comet Kohoutek." Skylab: Our First Space Station, chapter 9: 138. Prepared by George C. Marshall Space Flight Center. NASA SP-400. Washington DC: National Aeronautics and Space Administration Scientific and Technical Information Office, 1977.
Available @ https://history.nasa.gov/SP-400/ch9.htm

Compton, W. David; and Charles D. (Dunlap) Benson. “17. The Last Mission.” Living and Working in Space: A History of Skylab, Part III. The Missions and Results, 1973-1979: 312-338. NASA History Series. NASA SP-4208. Washington DC: National Aeronautics and Space Administration Scientific and Technical Information Branch, 1983.
Available @ https://history.nasa.gov/SP-4208/ch17.htm

Evans, Ben. “Five Decades of Celebrating Christmas in Space (Part 1).” AmericaSpace. Dec. 26, 2015.
Available @ https://www.americaspace.com/2015/12/26/ding-dong-merrily-on-orbit-celebrating-christmas-in-space-part-1/

Hathaway, David H. “The Skylab Missions.” NASA Marshall Space Flight Center Solar Physics > Previous Projects > Skylab. Last updated Aug. 11, 2014.
Available @ https://solarscience.msfc.nasa.gov/Skylab.shtml

Kramer, Herbert J. “Skylab.” ESA Earth Online > eoPortal Directory > Satellite Missions > S.
Available @ https://earth.esa.int/web/eoportal/satellite-missions/s/skylab

LePage, Andrew. “Christmas 1973 on Skylab.” Drew Ex Machina. Dec. 24, 2014.
Available @ https://www.drewexmachina.com/2014/12/24/christmas-1973-on-skylab/

Marriner, Derdriu. “Skylab 4 Observed Comet Kohoutek November 1973 to February 1974.” Earth and Space News. Wednesday, Nov. 11, 2020.
Available @ https://earth-and-space-news.blogspot.com/2020/11/skylab-4-began-observing-comet-kohoutek.html

Rusnak, Kevin M. “William R. Pogue Oral History Interviews.” NASA Johnson Space Center History Portal > NASA Johnson Space Center Oral History Project. July 17, 2000.
Available @ https://historycollection.jsc.nasa.gov/JSCHistoryPortal/history/oral_histories/PogueWR/poguewr.htm

Shayler, David J.; and Colin Burgess. NASA’s Scientist-Astronauts. Springer-Praxis Books in Space Exploration. Chichester UK: Praxis Publishing Limited, 2007.

Wednesday, December 16, 2020

Skylab 4 Imaged Comet Kohoutek’s Hydrogen Halo November 1973 to February 1974

Summary: Skylab 4 imaged Comet Kohoutek’s hydrogen halo November 1973 to February 1974 with Apollo 16 mission’s backup far-ultraviolet electrographic camera.

geometry of pre-perihelion observation of Comet Kohoutek; C.A. Lundquist, Skylab’s Astronomy and Space Sciences (1979), Figure 4-7: "Work of the US Gov. Public Use Permitted," via NASA History

Skylab 4 imaged Comet Kohoutek’s hydrogen halo November 1973 to February 1974 with the Apollo 16 mission’s backup far-ultraviolet electrographic Schmidt camera as the recently discovered comet made its closest passage to the sun.

Czech astronomer Luboš Kohoutek (born Jan. 29, 1935) is credited with discovering the long-period comet via plates taken Wednesday, March 7, 1973, at northern Germany’s Hamburg Observatory (Hamburger Sternwarte). Calculations placed Friday, Dec. 28, 1973, as the date for the comet’s reach of perihelion (Ancient Greek: περί, perí, “near” + ἥλιος, hḗlios, “sun”).

The National Aeronautics and Space Administration (NASA) revised time parameters for Skylab 4, the third manned mission to the first United States space station, to overlap with Comet Kohoutek’s December 1973 to January 1974 perihelion passage. Skylab 4 launched Friday, Nov. 16, 1973, at 14:01:23 Coordinated Universal Time (9:01 a.m. Eastern Standard Time) from east central Florida’s John F. Kennedy Space Center. The Apollo module’s successful Pacific Ocean splashdown Friday, Feb. 8, 1974, at 15:16:53 UTC (10:16 a.m. EST) signaled the completion of the Skylab 4 mission.

Gerald Paul Carr (born Aug. 22, 1932) commanded the Skylab 4 mission. Edward George Gibson (born Nov. 8, 1936) and William Reid Pogue (Jan. 23, 1930-March 3, 2014) participated as the mission’s scientist pilot and pilot, respectively. All three astronauts logged their first, and only, spaceflight via the Skylab 4 mission.

The mission’s Experiment S201 called for imaging the immense hydrogen halo layering outside the comet’s fuzzy coma. Thornton Leigh Page (Aug. 13, 1913-Jan. 2, 1996) of the United States Naval Research Laboratory (NRL) and NASA’s Lyndon B. Johnson Space Center, served as the experiment’s principal investigator. S201 necessitated a far-ultraviolet electrographic Schmidt camera, an instrument not already among Skylab’s onboard instrumentation array.

Page had collaborated with George Robert Carruthers (born Oct. 1, 1939) in the S201 far-ultraviolet camera study that was conducted as part of the Apollo Lunar Surface Experiments Package (ALSEP) during the Apollo 16 mission’s stay on the lunar surface in April 1972. Carruthers is credited with inventing and building the experiment’s gold-plated, electrographic Schmidt camera-based instrument, which was left at the Apollo 16 mission’s landing site in the Descartes Highlands in the central lunar highlands.

The Naval Research Laboratory minorly modified a backup model of Carruthers’ lunar surface camera to allow for observations at Skylab space station via the antisolar Scientific Air Lock (SAL), the Articulated Mirror System (AMS) or Extravehicular Activity (EVA). The modified camera journeyed with Skylab 4 mission’s crew to the space station in Apollo Command and Service Module (CSM) 118.

Between Monday, Nov. 26, 1973, and Saturday, Feb. 2, 1974, the far-ultraviolet camera captured 126 frames of Comet Kohoutek. In his preliminary report on Skylab’s far-ultraviolet photographs of Comet Kohoutek, published in 1975, Thornton Page announced that 30 of the frames had been “. . . measured for analysis of the comet’s hydrogen halo on nine separate dates from 31.7 days pre-perihelion to 13.0 days post-perihelion” (page 37).

The hydrogen halo’s brightness and diameter were plotted relative to time and comet-to-sun distance. An expected increase in the halo generally occurred with decreasing distance. Page noted, however, “an unexpected pre-perihelion maximum” on Wednesday, Dec. 12, at a comet-to-sun distance of 0.6 astronomical units (au) (89,758,722 kilometers; 55,773,484 miles). Page’s analysis found a much larger ratio of peak nuclear brightness to diameter near perihelion. “Such an increase in ‘concentration’ of the hydrogen halo might be expected from the increase in hydrogen production from the comet nucleus near perihelion,” he explained (page 55, 64).

The takeaways for Skylab 4’s images of Comet Kohoutek’s hydrogen halo are that the halo showed an unexpected increase in brightness and diameter on Wednesday, Dec. 12, and that images were obtained by one of the backup far-ultraviolet electrographic cameras invented by principal investigator Thornton Page’s Naval Research Laboratory colleague George Roberts Carruthers for the Apollo 16 mission.

six frames of Skylab 4 Far Ultraviolet Electronographic (S201 experiment) show Comet Kohoutek’s halo; NASA ID s74-20010: NASA, Generally not subject to copyright in the United States; may use this material for educational or informational purposes, including photo collections, textbooks, public exhibits, computer graphical simulations and Internet Web pages; general permission extends to personal Web pages, via NASA Image and Video Library

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

geometry of pre-perihelion observation of Comet Kohoutek; C.A. Lundquist, Skylab’s Astronomy and Space Sciences (1979), Figure 4-7: "Work of the US Gov. Public Use Permitted," via NASA History @ https://history.nasa.gov/SP-404/ch4.htm

Carruthers, George R.; and Thornton Page. “The S201 Far-Ultraviolet Imaging Survey: A Summary of Results and Implications for Future Surveys.” Publications of the Astronomical Society of the Pacific, vol. 96 (June 1984): 447-462.
Available via Harvard ADSABS (NASA Astrophysics Data System Abstracts) @ http://adsabs.harvard.edu/full/1984PASP...96..447C

Chapman, Robert D. Comet Kohoutek: A Teachers’ Guide With Student Activities. Greenbelt MD: NASA/Goddard Space Flight Center Office of Public Affairs Educational Programs Branch, September 1973.
Available @ https://files.eric.ed.gov/fulltext/ED093617.pdf

Compton, W. (William) David; and Charles D. Benson. “Appendix F: Comet Kohoutek.” Living and Working in Space: A History of Skylab. NASA SP-4208. Washington DC: National Aeronautics and Space Administration Scientific and Technical Information Branch, 1983.
Available @ https://history.nasa.gov/SP-4208/app.f.htm

Hendrie, Michael J. “Comet Kohoutek 1983f.” Journal of the British Astronomical Association, vol. 110, no. 1 (February 2000): 9-19.
Available via Harvard ADSABS (NASA Astrophysics Data System Abstracts) @ http://adsabs.harvard.edu/full/2000JBAA..110....9H

Kürti, Stefan. “Luboš Kohoutek.” Stefan Kürti Astro Web (SKAW) > Comets > Czech & Slovak Comet Discoverers.
Available @ http://www.skaw.sk/comet-discoverer-lubos-kohoutek.htm

Lundquist, Charles A., ed. “Appendix: Skylab’s Astronomy and Space Science Experiments.” Skylab’s Astronomy and Space Sciences: 116-117. NASA SP-404. Washington DC: National Aeronautics and Space Administration Scientific and Technical Information Office, 1979.
Available @ https://history.nasa.gov/SP-404/appendix.htm

Lundquist, C. (Charles) A.; and P.D. Craven. Kohoutek Photometric Photography Experiment (S233) Final Report. NASA TM-82449. Huntsville AL: George C. Marshall Space Flight Center.
Available @ https://archive.org/details/NASA_NTRS_Archive_19820007134/

Page, Thornton. "Fig. 3. Six views of the Comet Kohoutek Lyman-alpha halo." Page 302. "Far-UV Observations of Comet Kohoutek and Other Targets With the S201 Electronographic Camera on Skylab 4." Electrography and Astronomical Applications; Proceedings of the Conference, Austin, Texas, March 11, 12, 1974. (A75-23926 09-89) Austin, University of Texas, 1974: pages 297-305.
Available via Harvard ADSABS (NASA Astrophysics Data System Abstracts) @ https://articles.adsabs.harvard.edu/full/1974eaa..conf..297P
Available via Harvard ADSABS (NASA Astrophysics Data System Abstracts) @ https://articles.adsabs.harvard.edu/pdf/1974eaa..conf..297P

Page, Thornton. “S201 Far-Ultraviolet Photographs of Comet Kohoutek From Skylab 4 (SL4) (Preliminary Report).” Pages 37-75. In: Gilmer Allen Gary, ed. Comet Kohoutek: A Workshop Held at Marshall Space Flight Center Huntsville, Alabama June 13-14, 1974. Washington DC: National Aeronautics and Space Administration, 1975.
Available via Internet Archive @ https://archive.org/details/CometKohoutek/page/n47

Smithsonian National Air and Space Museum. “Dr. Carruthers’ Telescope.” Smithsonian National Air and Space Museum > Later Missions > Apollo 16.
Available @ https://airandspace.si.edu/exhibitions/apollo-to-the-moon/online/later-missions/apollo-16.cfm

uhoh. “How Did Skylab’s Electrographic Camera Work?” Space Exploration Stack Exchange > Questions. Dec. 1, 2018.
Available @ https://space.stackexchange.com/questions/32497/how-did-skylabs-electrographic-camera-work

uhoh. “How Was the Moon’s First Telescope Used? (Apollo 16).” Space Exploration Stack Exchange > Questions. Jan. 11, 2019.
Available @ https://space.stackexchange.com/questions/33504/how-was-the-moons-first-telescope-used-apollo-16

Wade, Mark. “Skylab 4.” Astronautix > Alphabetical Index > S.
Available @ http://www.astronautix.com/s/skylab4.html

Whipple, Fred L. “Comets in the Space Age.” The Astrophysical Journal, vol. 341 (June 1, 1989): 1-15.
Available via Harvard ADSABS (NASA Astrophysics Data System Abstracts) @ http://adsabs.harvard.edu/full/1989ApJ...341....1W

Wednesday, November 11, 2020

Skylab 4 Began Observing Comet Kohoutek in November 1973

Summary: The Skylab 4 mission began observing Comet Kohoutek in November 1973 as the recently discovered comet orbited through the inner solar system.

artist’s concept of observations of Comet Kohoutek by Skylab 4 astronauts through the scientific airlock in the space station’s Orbital Workshop; illustration created Nov. 27, 1973; NASA ID s73-37274: NASA, Generally not subject to copyright in the United States; may use this material for educational or informational purposes, including photo collections, textbooks, public exhibits, computer graphical simulations and Internet Web pages; general permission extends to personal Web pages, via NASA Image and Video Library

The Skylab 4 mission began observing Comet Kohoutek in November 1973 as the recently discovered long-period comet continued its passage through the inner solar system.

Czech astronomer Luboš Kohoutek (born Jan. 29, 1935) discovered Comet Kohoutek at the Hamburg Observatory (Hamburger Sternwarte) in northern Germany. Officially designated as C/1973 E1, Comet Kohoutek was discovered Wednesday, March 7, 1973, in the direction of Hydra the Sea Serpent Constellation, according to NASA Goddard Space Flight Center astronomer Robert D. Chapman in Comet Kohoutek: A Teacher's Guide (1973). Calculations identified Friday, Dec. 28 as the date of the newly discovered comet’s perihelion (Ancient Greek: περί, perí, “near” + ἥλιος, hḗlios, “sun”), closest passage to the sun.

In response to Kohoutek’s discovery, the National Aeronautics and Space Administration (NASA) initiated Operation Kohoutek, headed by Stephen Paul Maran, an astrophysicist at NASA’s Goddard Space Flight Center since 1969. The multi-resource program aimed to coordinate widespread ground, air and space observations of the comet.

Skylab 4 launched Friday, Nov. 16, 1973, at 14:01:23 Coordinated Universal Time (9:01 a.m. Eastern Standard Time) from Cape Canaveral, east central Florida, as NASA’s third manned mission to Skylab, the first United States space station. The three-astronaut crew comprised Gerald Paul Carr (born Aug. 22, 1932) as commander; Edward George Gibson (born Nov. 8, 1936) scientist pilot; and William Reid Pogue (Jan. 23, 1930-March 3, 2014) as the mission’s pilot. The mission’s Apollo Command and Service Module (CSM) 118 docked at Skylab at 21:55:00 UTC (4:55 p.m. EST). The mission’s Apollo Command and Service Module (CSM) 118 docked at Skylab at 21:55:00 UTC (4:55 p.m. EST).

NASA finessed the Skylab 4 mission’s time parameters to maximize perihelion-centered observations. As Charles Lundquist, director of the Space Sciences Laboratory at NASA’s George C. Marshall Space Flight Center in Huntsville, Alabama, explained in Skylab’s Astronomy and Space Sciences (1979): “It is during this period that the most interesting and dramatic changes happen to comets, and it is also during this period that observations from the Earth’s surface are hardest to make or even impossible because light from the nearby Sun is scattered by the Earth’s atmosphere into instruments aimed at the comet” (page 43).

“Systematic comet observations” were initiated on Friday, Nov. 23, according to authors William David Compton and Charles Dunlap Benson in Living and Working in Space: A History of Skylab, published by NASA in 1983. The camera associated with Charles Lundquist’s photometric studies (Skylab Experiment S233) was designated as the first instrument to gather data on the comet. Photometry concerns measurement of visible light in terms of human perception of light’s brightness.

The Skylab space station’s 35-mm Nikon camera, which had a 55-mm focal length and a focal range from two feet to infinity, was used for the experiment. Four cassettes of 60-exposure Kodak Plus-X Aerial 3401 film were supplied for the experiment.

Calibrated photometric data was to be obtained from a twice daily observational sequence of defocused and in-focus photographs. Defocused photographs of the coma and starfields were to be obtained at a specified focus setting of 15 feet. Long duration in-focus photographs were to record as much of the comet’s tail structure as possible. In his final report of the experiment, published in 1981, Charles Lundquist explained that the operation plan of twice daily photographs “. . . could serve as a reference record of the gross changes in the comet appearance and magnitude” (page 2).

The photometric study’s photographs were taken inside the space station. Photography sessions took place at window number one (CM-1) in the Apollo Command and Service Module (CSM) and windows three (STS-243; S-3) and four (STS-242; S-4) in the Structural Transition Section (STS) linking the station’s Airlock Module (AM) and Multiple Docking Adaptor (MDA). The mission’s astronauts were responsible for manually pointing the Nikon camera at the comet. The George C. Marshall Space Center’s MSFC Skylab Kohoutek Project Report, published in 1974, noted that “. . . the astronauts taped the camera to a rotatable mirror structure over the CM-1 window and improvised cardboard to tape the camera in place at the STS-242 and STS-243 windows” (page 43).

Pilot Pogue is credited with the last photographs for Experiment S233. Frame 52, at the infinity setting, and frame 53, at the 15-foot focal length, were obtained Feb. 5, 1974, at 01:03 UTC (9:03 p.m. Eastern Daylight Time, Monday, Feb. 4, 1974). Pogue was stationed at window four (STS-4; S-4) in the Structural Transition Section.

The takeaways for Skylab 4 beginning observations of Comet Kohoutek in November 1973 are that the mission’s time parameters coincided with the recently discovered comet’s perihelion passage between December 1973 and February 1974 and that the first Kohoutek-based experiment operated from Friday, Nov. 23, 1973, to Monday, Feb. 5, 1974.

Comet Kohoutek’s perihelion passage December 1973 to February 1974; C.A. Lundquist, Skylab’s Astronomy and Space Sciences (1979), Figure 4-6: "Work of the US Gov. Public Use Permitted," via NASA History

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

Brun, Nancy L. Astronautics and Aeronautics, 1974: A Chronology. The NASA History Series. NASA SP-4019. Washington DC: National Aeronautics and Space Administration Scientific and Technical Information Office, 1977.
Available @ https://history.nasa.gov/AAchronologies/1974.pdf

Butler, Carol. “Edward G. Gibson Oral History Interviews.” NASA Johnson Space Center History Portal > NASA Johnson Space Center Oral History Project. Dec. 1, 2000.
Available @ https://historycollection.jsc.nasa.gov/JSCHistoryPortal/history/oral_histories/GibsonEG/gibsoneg.htm

Kürti, Stefan. “Luboš Kohoutek.” Stefan Kürti Astro Web (SKAW) > Comets > Czech & Slovak Comet Discoverers.
Available @ http://www.skaw.sk/comet-discoverer-lubos-kohoutek.htm

Library of Congress Science and Technology Division. Astronautics and Aeronautics, 1973: Chronology of Science, Technology, and Policy. Sponsored by NASA Historical Office. NASA SP-4018. Washington DC: National Aeronautics and Space Administration Scientific and Technical Information Office, 1975.
Available @ https://history.nasa.gov/AAchronologies/1973.pdf

Lundquist, C. (Charles) A.; and P. (Paul) D. Craven. Kohoutek Photometric Photography Experiment (S233) Final Report. NASA TM-82449. Huntsville AL: George C. Marshall Space Flight Center.
Available @ https://archive.org/details/NASA_NTRS_Archive_19820007134/

Mars, Kelli. “Skylab 4: Final Mission Launches to Skylab.” NASA > NASA History. Nov. 15, 2018.
Available @ https://www.nasa.gov/feature/skylab-4-final-mission-launches-to-skylab

NASA Marshall Space Flight Center Public Affairs Office. “Skylab Operations Summary.” NASA/Kennedy Space Center > Space Flight Archives > Skylab > Program Overview.
Available @ https://science.ksc.nasa.gov/history/skylab/skylab-operations.txt

Newkirk, Roland W.; Ivan D. Ertel; and Courtney G. Brooks. Skylab: A Chronology. The NASA History Series. NASA SP-4011. Washington DC: National Aeronautics and Space Administration Scientific and Technical Information Branch, 1977.
Available via NASA History @ https://history.nasa.gov/SP-4011/contents.htm
Available via NASA NTRS (NASA Technical Reporters Server) @ https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19780017172.pdf

Rusnak, Kevin M. “Gerald P. Carr Oral History Interviews.” NASA Johnson Space Center History Portal > NASA Johnson Space Center Oral History Project. Oct. 25, 2000.
Available @ https://historycollection.jsc.nasa.gov/JSCHistoryPortal/history/oral_histories/CarrGP/carrgp.htm

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