Payload specialist

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

A payload specialist (PS) was an individual selected and trained by commercial or research organizations for flights of a specific payload on a NASA Space Shuttle mission. People assigned as payload specialists included individuals selected by the research community, a company or consortium flying a commercial payload aboard the spacecraft, and non-NASA astronauts designated by international partners.

The term refers to both the individual and to the position on the Shuttle crew.


Payload specialists usually fly for a single specific mission. Chosen outside the standard NASA Astronaut Corps selection process, they are exempt from certain NASA requirements such as colorblindness.[1] Payload specialists were not required to be United States citizens, but had to be approved by NASA and undergo rigorous training. In contrast, a Space Shuttle mission specialist was selected as a NASA astronaut first and then assigned to a mission.

Payload specialists on early missions were technical experts to join specific payloads such as a commercial or scientific satellite. On Spacelab and other missions with science components, payload specialists were scientists with expertise in specific experiments. The term also applied to representatives from partner nations who were given the opportunity of a first flight on board of the Space Shuttle (such as Saudi Arabia and Mexico), and to Congressmen and the Teacher in Space program.

Other positions on board Space Shuttle were mission commander, pilot, and mission specialist. Unlike other Shuttle crew, international or scientific payload specialists were generally assigned a back-up who trained alongside the primary payload specialist and would replace him/her in the event of illness or other disability.

Payload specialists operated experiments, and participated in experiments needing human subjects. Charles D. Walker recalled after working with Rhea Seddon's echocardiograph on STS-51-D, "Jake and I were the obvious subjects. We really didn’t have much of a choice in whether we were going to be subjects or not. 'You're a payload specialist; you’re going to be a subject.'" Besides his own electrophoresis work, Walker operated an unrelated experiment for the University of Alabama Birmingham, and helped build homemade repair tools for a satellite launched on the mission.[2]

Payload specialists were flown from 1983 (STS-9) to 2003 (STS-107). The last flown payload specialist was the first Israeli astronaut, Ilan Ramon, who was killed in the Columbia disaster on mission STS-107 with the rest of the crew.


NASA's payload specialist program has been criticized for giving limited Shuttle flight positions to civilian aerospace engineers such as Greg Jarvis (killed aboard Challenger), politicians such as US Representative Bill Nelson, and other civilians such as Teacher in Space Christa McAuliffe (also killed aboard Challenger). Even the rationale for the Shuttle flight of former Mercury astronaut and US Senator John Glenn was questioned.[3] The concern was that these people had replaced career astronauts in very limited flight opportunities, and some may have flown without understanding the level of danger.

A 1986 post-Challenger article in The Washington Post reviewed the issue, reporting that as far back as 1982, NASA was concerned with finding reasonable justifications for flying civilians on the Shuttle as was directed by the Reagan administration. The article says that "A review of records and interviews with past and present NASA and government officials shows the civilian program's controversial background, with different groups pushing for different approaches."[4] The article concludes with:

Author Tom Wolfe, who chronicled the early days of the space program in The Right Stuff, wrote after the Challenger explosion that support for the citizen program, and therefore McAuliffe's place aboard the ill-fated shuttle, was part of an insiders' battle. NASA civilians, pitting themselves against the professional astronauts, used the program for the "dismantling of Astropower," which Wolfe described as "the political grip the original breed of fighter-pilot test-pilot astronauts had on NASA."[4]

List of all payload specialists[edit]

Until Challenger[edit]

Payload specialist Mission Notes
Ulf Merbold STS-9 first payload specialists, Ulf Merbold was the first international (German) payload specialist
Byron K. Lichtenberg
Charles D. Walker STS-41-D first non government-affiliated payload specialist
Marc Garneau STS-41-G Garneau was the first Canadian in space, Scully-Power the first Australian
Paul Scully-Power
Gary Payton STS-51-C first military payload specialist
Charles D. Walker STS-51-D
Jake Garn then-U.S. Senator, first U.S. legislative branch payload specialist
Lodewijk van den Berg STS-51-B
Taylor Wang
Patrick Baudry STS-51-G two international payload specialists
Sultan bin Salman Al Saud
Loren Acton STS-51-F
John-David F. Bartoe
William A. Pailes STS-51-J
Reinhard Furrer STS-61-A three international payload specialists, most payload specialists on a single flight
Ernst Messerschmid
Wubbo Ockels
Rodolfo Neri Vela STS-61-B first Mexican in space
Charles D. Walker Walker's third and final spaceflight
Robert J. Cenker STS-61-C
Bill Nelson then-U.S. Representative, second and final U.S. legislative branch payload specialist
Gregory Jarvis STS-51-L killed in the Challenger disaster
Christa McAuliffe

Post-Challenger to Columbia[edit]

Payload specialist Mission Notes
Samuel T. Durrance STS-35 first post-Challenger payload specialists
Ronald A. Parise
F. Drew Gaffney STS-40
Millie Hughes-Fulford
Thomas J. Hennen STS-44
Roberta Bondar STS-42
Ulf Merbold
Byron K. Lichtenberg STS-45
Dirk Frimout first Belgian in space
Lawrence J. DeLucas STS-50
Eugene H. Trinh
Franco Malerba STS-46 first Italian in space
Mamoru Mohri STS-47 first Japanese astronaut on board Space Shuttle
Steve MacLean STS-52
Ulrich Walter STS-55
Hans Schlegel
Martin J. Fettman STS-58
Chiaki Mukai STS-65
Samuel T. Durrance STS-67
Ronald A. Parise
Frederick W. Leslie STS-73
Albert Sacco
Umberto Guidoni STS-75
Jean-Jacques Favier STS-78
Robert Thirsk
Roger K. Crouch STS-83
Gregory T. Linteris
Roger K. Crouch STS-94 mission reflight
Gregory T. Linteris
Bjarni Tryggvason STS-85
Leonid Kadeniuk STS-87 Ukrainian payload specialist
Jay C. Buckey STS-90 final Spacelab mission
James A. Pawelczyk
Chiaki Mukai STS-95
John Glenn final American payload specialist
Ilan Ramon STS-107 first Israeli in space, final payload specialist, killed in the Columbia disaster

Alternate and back-up (not flown) payload specialists[edit]

This section needs to be completed

Wubbo Ockels, Michael Lampton

Robert Thirsk, Robert E. Stevenson

Keith Wright

Mary Johnston, Eugene H. Trinh

Jean-Loup Chrétien, Abdulmohsen Al-Bassam

George W. Simon, Diane K. Prinz

Ulf Merbold

Robert W. Phillips

Michael Lampton, Charles R. Chappell

Joseph M. Prahl, Albert Sacco

Jean-Jacques Favier

David H. Matthiesen, R. Glynn Holt

Pedro Duque, Luca Urbani

Alan Johnston, Paul Ronney

Alan Johnston, Paul Ronney

Yaroslav Pustovyi[5]

Alexander W. Dunlap, Chiaki Mukai

Other statistics[edit]

Multiple flights[edit]

Flights Payload specialist
3 Charles Walker
2 Ulf Merbold, Byron K. Lichtenberg, Samuel T. Durrance, Ronald A. Parise, Chiaki Mukai, Roger Crouch, Greg Linteris
No. of payload specialists flights Country
36 Flag of the United States.svg United States
6 Flag of Germany.svg Germany
5 Flag of Canada.svg Canada
3 Flag of Japan.svg Japan
2 Flag of France.svg France
2 Flag of Italy.svg Italy
1 Flag of Saudi Arabia.svg Saudi Arabia
1 Flag of the Netherlands.svg The Netherlands
1 Flag of Mexico.svg Mexico
1 Flag of Belgium.svg Belgium
1 Flag of Ukraine.svg Ukraine
1 Flag of Israel.svg Israel
Total 60 payload specialist flight opportunities

Payload specialists who trained later as mission specialists[edit]

All were international astronauts.

See also[edit]


  1. ^ Collins, Debbie. "The Power of Persistence". NASA. Retrieved 2020-06-21.
  2. ^ Walker, Charles D. (14 April 2005). "Oral History Transcript". NASA Johnson Space Center Oral History Project (Interview). Interviewed by Johnson, Sandra.
  3. ^ Oberg, James. "NASA hypes "Glenn Mission" Science". Retrieved 4 March 2017.
  4. ^ a b Pincus, Walter. "NASA's Push to Put Citizen in Space Overtook Fully 'Operational' Shuttle". The Washington Post. Retrieved 4 March 2017.
  5. ^ Ramsay, Janis (21 February 2015). "Barrie astronaut continues to keep eye on skies". Barrie Advance. Retrieved 10 January 2019.

External links[edit]