STS-75 was a 1996 NASA Space Shuttle mission, the 19th mission of the orbiter.

Crew

Crew seat assignments

{| class="wikitable" style="text-align:center"

|-

! Seat

! Launch

! Landing

|rowspan=8| 150px<br />Seats 1–4 are on the flight deck.<br />Seats 5–7 are on the mid-deck.

|-

! 1

|colspan=2| Allen

|-

! 2

|colspan=2| Horowitz

|-

! 3

|Hoffman

|Nicollier

|-

! 4

|colspan=2| Cheli

|-

! 5

|Nicollier

|Hoffman

|-

! 6

|colspan=2| Chang-Diaz

|-

! 7

|colspan=2| Guidoni

|}

Mission objective

Tethered Satellite System

The primary objective of STS-75 was to carry the Tethered Satellite System Reflight (TSS-1R) into orbit and to deploy it spaceward on a conducting tether. The mission also flew the United States Microgravity Payload (USMP-3) designed to investigate materials science and condensed matter physics.

The TSS-1R mission was a reflight of TSS-1 which was flown onboard Space Shuttle Atlantis on STS-46 in July/August 1992. The Tether Satellite System circled the Earth at an altitude of 296 kilometers, placing the tether system within the rarefied electrically charged layer of the atmosphere known as the ionosphere.

STS-75 mission scientists hoped to deploy the tether to a distance of . Over of the tether were deployed (over a period of 5 hours) before the tether broke. Many pieces of floating debris were produced by the plasma discharge and rupture of the tether, and some collided with it. The satellite remained in orbit for a number of weeks and was easily visible from the ground.

thumb|left|alt=TSS-1R|TSS-1R tether composition [NASA]

The electric conductor of the tether was a copper braid wound around a nylon (Nomex) string. It was encased in teflon-like insulation, with an outer cover of kevlar, inside a nylon (Nomex) sheath. The culprit turned out to be the innermost core, made of a porous material which, during its manufacture, trapped many bubbles of air, at atmospheric pressure.

First use of Linux in space

STS-75 also was the first use of an operating system based on the Linux kernel on orbit. An older Digital Unix program, originally on a DEC AlphaServer, was ported to run Linux on a laptop. The next use of Linux was a year later, on STS-83.

Fictional STS-75 mission

STS-75 was the shuttle mission described in the fictional NASA Document 12-571-3570, although this document was disseminated several years before STS-75 was launched. The document purports to report on experiments to determine effective sexual positions in microgravity. Astronomer and scientific writer Pierre Kohler mistook this document for fact and is responsible for a major increase in its redistribution in the early 21st century. Conspiracy theories first made in the early beginnings of the Shuttle era of sex in space were suddenly made rampant again, causing a minor press debacle among tabloids.

References

  • NASA mission summary
  • STS-75 Video Highlights