STS-55 (Space Transportation System 55), or D-2 was the 55th overall flight of the US Space Shuttle and the 14th flight of Shuttle Columbia. This flight was a multinational Spacelab flight involving 88 experiments from eleven different nations. The experiments ranged from biology sciences to simple earth observations.

STS-55 Spacelab
Spacelab in Columbia's payload bay
Mission typeResearch
COSPAR ID1993-027A
SATCAT no.22640
Mission duration9 days, 23 hours, 39 minutes, 59 seconds
Distance travelled6,701,603 kilometers (4,164,183 mi)
Orbits completed160
Spacecraft properties
SpacecraftSpace Shuttle Columbia
Landing mass103,191 kilograms (227,497 lb)
Payload mass11,539 kilograms (25,439 lb)
Crew size7
MembersSteven R. Nagel
Terence T. Henricks
Jerry L. Ross
Charles J. Precourt
Bernard A. Harris, Jr.
Ulrich Walter
Hans Schlegel
Start of mission
Launch date26 April 1993, 14:50 UTC
Launch siteKennedy LC-39A
End of mission
Landing date6 May 1993, 14:30 UTC
Landing siteEdwards Runway 22
Orbital parameters
Reference systemGeocentric
RegimeLow Earth
Perigee304 kilometres (189 mi)
Apogee312 kilometres (194 mi)
Inclination28.45 degrees
Period90.7 min
Sts-55 crew

Left to right - Seated: Henricks, Nagel, Precourt; Standing: Harris, Schlegel, Ross, Walter


Position Astronaut
Commander United States Steven R. Nagel
Fourth and last spaceflight
Pilot United States Terence T. Henricks
Second spaceflight
Mission Specialist 1 United States Jerry L. Ross
Fourth spaceflight
Mission Specialist 2 United States Charles J. Precourt
First spaceflight
Mission Specialist 3 United States Bernard A. Harris, Jr.
First spaceflight
Payload Specialist 1 Germany Ulrich Walter, DFVLR
Only spaceflight
Payload Specialist 2 Germany Hans Schlegel, DFVLR
First spaceflight

Backup crew

Position Astronaut
Payload Specialist 1 Germany Gerhard Thiele, DFVLR
Payload Specialist 2 Germany Renate Brümmer, DFVLR

Mission highlights

Columbia carried to orbit the second reusable German Spacelab on the STS-55 mission and demonstrated the shuttle's ability for international cooperation, exploration, and scientific research in space. The Spacelab Module and an exterior experiment support structure contained in Columbia’s payload bay comprised the Spacelab D-2 payload. (The first German Spacelab flight, D-1, flew Shuttle mission 61-A in October 1985.) The U.S. and Germany gained valuable experience for future space station operations.

The D-2 mission, as it was commonly called, augmented the German microgravity research program started by the D-1 mission. The German Aerospace Research Establishment (DLR) had been tasked by the German Space Agency (DARA) to conduct the second mission. DLR, NASA, the European Space Agency (ESA), and agencies in France and Japan contributed to D-2's scientific program. Eleven nations participated in the experiments. Of the 88 experiments conducted on the D-2 mission, four were sponsored by NASA.

The crew worked in two shifts around-the-clock to complete investigations into the areas of fluid physics, materials sciences, life sciences, biological sciences, technology, Earth observations, atmospheric physics, and astronomy. Many of the experiments advanced the research of the D-1 mission by conducting similar tests, using upgraded processing hardware, or implementing methods that took full advantage of the technical advancements since 1985. The D-2 mission also contained several new experiments which were not previously flown on the D-1 mission.

The mission surpassed the 365th day in space for the Space Shuttle fleet and the 100th day of flight time in space for Columbia, the fleet's oldest Orbiter, on its fourteenth flight.

D-2 marked the first tele-robotic capture of a free floating object by flight controllers in Germany. The crew conducted the first intravenous saline solution injection in space as part of an experiment to study the human body's response to direct fluid replacement as a countermeasure for amounts lost during space flight. They also successfully completed an in-flight maintenance procedure for collection of orbiter waste water, which allowed the mission to continue.

STS-55 crewmembers participated in two amateur radio experiments, SAREX II from the United States and the German SAFEX. These experiments allowed students and amateur radio operators from around the world to talk directly with the Space Shuttle in orbit and participated in a SpaceMedicine conference with the Mayo Clinic.


Columbia was initially scheduled to launch in late February. However, this date slipped to early March due to concerns with the tip-seal retainers in the main engines' oxidizer turbopumps. All three turbopumps were replaced at the pad but later inspection revealed the retainers to be in good condition.

Further delays were caused by the burst of a hydraulic flex hose in the aft compartment during the Flight Readiness Test. The lines were removed and inspected and three replacements were installed.

The launch attempt on 22 March was aborted automatically at T-3 seconds when computers detected an incomplete ignition of the number three Space Shuttle Main Engine. The problem was traced to a leak in the liquid oxygen preburner check valve. All three SSMEs were replaced as a precaution.

Another launch attempt on 24 April was scrubbed due to a possible faulty reading with one of the inertial measurement units.[1]

The final launch attempt was successful with liftoff at 10:50 am EDT on 26 April 1993.

See also


 This article incorporates public domain material from websites or documents of the National Aeronautics and Space Administration.

  1. ^ "NASA – STS-55". Retrieved 12 August 2010.

External links

Bernard A. Harris Jr.

Bernard Anthony Harris Jr. (born June 26, 1956 in Temple, Texas) is a former NASA astronaut. On February 9, 1995, Harris became the first African American to perform an extra-vehicular activity (spacewalk), during the second of his two Space Shuttle flights.

Charles J. Precourt

Charles Joseph Precourt (born June 29, 1955) is a retired NASA astronaut. His career in flight began at an early age, and spans his entire lifetime. He served in the US Air Force, piloted numerous jet aircraft, and piloted and commanded the Space Shuttle. Notably, he piloted or commanded several missions which involved docking with the Russian Mir space station and was heavily involved in Russian/US Space relations as well as the International Space Station collaboration. He retired from the USAF with the rank of Colonel.

European Astronaut Corps

The European Astronaut Corps is a unit of the European Space Agency (ESA) that selects, trains, and provides astronauts as crew members on U.S. and Russian space missions. As of Nov 2014, 24 ESA astronauts are now able to go board the ISS. There are currently 47 members of the Corps, 26 currently active. The European Astronaut Corps is based at the European Astronaut Centre in Cologne, Germany. They can be assigned to various projects both in Europe (at ESTEC, for instance) or elsewhere in the world, at NASA Johnson Space Center or Star City.

Gerhard Thiele

Dr. Gerhard Paul Julius Thiele (born September 2, 1953) is a German physicist and a former ESA astronaut.

Hans Schlegel

Hans Wilhelm Schlegel (Überlingen, 3 August 1951) is a German physicist, a former ESA astronaut, and a veteran of two NASA Space Shuttle missions.

Jerry L. Ross

Jerry Lynn Ross (born January 20, 1948, Crown Point, Indiana) is a retired United States Air Force officer and a former NASA astronaut. He is a veteran of seven Space Shuttle missions, making him the joint record holder for most spaceflights (a record he shares with Franklin Chang-Diaz). His papers, photographs and many personal items are in the Barron Hilton Flight and Space Exploration Archives at Purdue University. He was inducted into the Astronaut Hall of Fame during ceremonies in May 2014.

Ross is the author of Spacewalker: My Journey in Space and Faith as NASA's Record-Setting Frequent Flyer (Purdue University Press, 2013) with John Norberg. In March 2014 it was announced "Spacewalker" will be available in a French translation through the specialist aerospace publisher Altipresse.

Fellow astronaut Chris Hadfield describes Ross in his autobiography, An Astronaut's Guide to Life on Earth, as "the embodiment of the trustworthy, loyal, courteous and brave astronaut archetype."

List of African-American astronauts

African-American astronauts are people who have either traveled into space or been part of an astronaut program.

List of European astronauts

This is an incomplete list of astronauts who are resident in any of the countries of Europe, exclusive of the former Soviet republics of Russia, Belarus, and Ukraine.

List of astronauts by first flight

This is a list of astronauts by first flight, in chronological order. According to the Fédération Aéronautique Internationale, spaceflight is achieved by exceeding an altitude higher than 100 km (62 mi; 330,000 ft), thereby crossing the Kármán line. The United States Air Force considers an altitude of 50 mi (80 km; 260,000 ft) as the limit of space; United States Air Force and NASA personnel exceeding that altitude can be awarded the astronaut badge.

List of astronauts by name

This is an alphabetical list of astronauts, people selected to train for a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft.

For a list of everyone who has flown in space, see List of space travelers by name.

More than 560 people have been trained as astronauts. Until recently, astronauts were sponsored and trained exclusively by governments, either by the military or by civilian space agencies. However, with the advent of suborbital flight starting with privately funded SpaceShipOne in 2004, a new category of astronaut was created: the commercial astronaut.

While the term astronaut is sometimes applied to anyone who trains for travels into space—including scientists, politicians, journalists, and tourists—this article lists only professional astronauts, those who have been selected to train professionally. This includes national space programs, industry and commercial space programs which train and/or hire their own professional astronauts.

Names in italic are astronauts who have left Low Earth orbit, names in bold are astronauts who have walked on the moon. The flags indicate the astronaut's primary citizenship during his or her time as an astronaut. The symbol identifies female astronauts.

List of space travelers by nationality

The criteria for determining who has achieved human spaceflight vary. The FAI defines spaceflight as any flight over 100 kilometres (62 mi). In the United States, professional, military, and commercial astronauts who travel above an altitude of 80 kilometres (50 mi) are awarded astronaut wings. The majority of people who have flown into space have done so by entering Earth orbit. This list includes persons meeting all three criteria, in separate subdivisions.

The flags indicate the space traveler's nationality at the time of their flight or flights. In cases of dual citizenship, the space traveler is listed under their primary residence. A secondary list appended to the entry for the Soviet Union shows the birth countries of space travelers not born in Russia. A similar list after the entry for the United States shows the birth countries of space travelers who are or were citizens of the U.S. but were born elsewhere. Flags shown in the secondary lists are those in use at the time of the space travelers' birth.Names in italic are space travelers who are not part of any national astronaut program or astronaut corps (Toyohiro Akiyama, Helen Sharman, the Space Adventures customers and the sub-orbital SpaceShipOne pilots).

Except for the SpaceShipOne pilots, all of the space travellers have been crew or participants aboard flights launched by China, the Soviet Union/Russia or the United States.

NASA Astronaut Group 11

NASA Astronaut Group 11 was a group of 13 astronauts announced on 23 May 1985.

NASA Astronaut Group 13

NASA Astronaut Group 13 (the Hairballs) was a group of 23 astronauts announced by NASA on 17 January 1990. The group name came from its selection of a black cat as a mascot, to play against the traditional unlucky connotations of the number 13.

NASA Astronaut Group 17

NASA Astronaut Group 17, (the Penguins), were chosen by NASA in 1998. The group of 32 candidates included eight pilots, 17 mission specialists, and seven international mission specialists who become NASA astronauts. They began training in August 1998.


STS-56 was a Space Shuttle Discovery mission to perform special experiments. The mission was launched from Kennedy Space Center, Florida, on 8 April 1993.

Shuttle Amateur Radio Experiment

The Shuttle Amateur Radio Experiment (SAREX), later called the Space Amateur Radio Experiment, was a program that promoted and supported the use of amateur ("ham") radio by astronauts in low earth orbit aboard the United States Space Shuttle to communicate with other amateur radio stations around the world. It was superseded by the Amateur Radio on the International Space Station (ARISS) program. SAREX was sponsored by NASA, AMSAT (The Radio Amateur Satellite Corporation), and the ARRL (American Radio Relay League).

Steven R. Nagel

Steven Ray Nagel (October 27, 1946 – August 21, 2014), (Col, USAF), was an American astronaut, aeronautical and mechanical engineer, test pilot, and a United States Air Force pilot.

Terence T. Henricks

Terence Thomas "Tom" Henricks (born July 5, 1952) is a retired colonel in the United States Air Force and a former NASA astronaut. He served on four Space Shuttle missions.

Ulrich Walter

Prof. Dr. Ulrich Hans Walter (born February 9, 1954) is a German physicist/engineer and a former DFVLR astronaut.

Walter was born in Iserlohn. After finishing secondary school there and two years in the Bundeswehr, he studied physics at the University of Cologne. In 1980, he was awarded a diploma degree, and five years later a doctorate, both in the field of solid-state physics.

After two post-doc positions at the Argonne National Laboratory, Chicago, Illinois, and the University of California at Berkeley, California, he was selected in 1987 to join the German astronaut team. From 1988 to 1990, he completed basic training at the German Aerospace Center, and was then nominated to be in the prime crew for the second German Spacelab mission.

In 1993, he flew on board the Space Shuttle Columbia on mission STS-55 (Spacelab D-2) as a Payload Specialist. He spent 9 days, 23 hours, and 40 minutes in space.

After his spaceflight. he worked for another four years at DLR, managing a space imaging database project. When the German astronaut team was merged into a European Space Agency, he did not transfer, but resigned to work at IBM Germany.

Since 2003, he has been a full professor at the Technische Universität München (Munich, Germany), holding the chair of the Institute of Astronautics (space technology) at the University's faculty of mechanical engineering.

He is author of several books, and also does work as presenter of a popular science magazine shows, such as MaxQ on Bavarian TV.

He received an honorary doctorate from the Kyiv Polytechnic Institute, Ukraine (2012).

Walter is married, has two children, and lives near Munich, Germany.

See also
Earth-based research
Spacecraft used
Mission highlights

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