STS-43

Key takeaways

STS-43 belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect STS-43 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of STS-43 from memory before moving on to harder problems.

Reference excerpt

STS-43, the ninth mission for Space Shuttle Atlantis, was a nine-day mission whose primary goal was launching the TDRS-E satellite (TDRS-5). The flight also tested an advanced heatpipe radiator for potential use on the then-future space station and conducted a variety of medical and materials science investigations.

Crew

Crew seat assignments

Preparations and launch

The launch took place on August 2, 1991 at 15:02:00 UTC (11:02 am EDT, local time at the launch site). Launch was originally set for July 23, 1991, but was moved to July 24 to allow time to replace a faulty integrated electronics assembly that controls orbiter/external tank separation. The mission was postponed again about five hours before liftoff on July 24, 1991, due to a faulty main engine controller on the number three main engine. The controller was replaced and retested; launch was reset for August 1, 1991. Liftoff set for 11:01 a.m. delayed due to cabin pressure vent valve reading and postponed at 12:28 p.m. due to unacceptable return-to-launch site weather conditions. Launch finally occurred on August 2, 1991, without further delays.

Mission highlights

The primary payload, TDRS-E, attached to an Inertial Upper Stage (IUS), was deployed about six hours into flight, and the IUS propelled the satellite into geosynchronous orbit. TDRS-5 became the fourth member of the orbiting TDRS cluster. Secondary payloads were Space Station Heat Pipe Advanced Radiator Element (SHARE II); Shuttle Solar Backscatter Ultra-Violet (SSBUV) instrument; Tank Pressure Control Equipment (TPCE) and Optical Communications Through Windows (OCTW). Other experiments included Auroral Photography Experiment (APE-B) Protein Crystal Growth Ill (PCG Ill); Bioserve / Instrumentation Technology Associates Materials Dispersion Apparatus (BIMDA); Investigations into Polymer Membrane Processing (IPMP); Space Acceleration Measurement System (SAMS); Solid Surface Combustion Experiment (SSCE); Ultraviolet Plume imager (UVPI); and the Air Force Maui Optical Site (AMOS) experiment. TDRS-E, which became TDRS-5 on orbit, was successfully boosted to geosynchronous orbit at more than 22,000 miles (35,400 km (22,000 mi)) above Earth by two firings of the Inertial Upper Stage (IUS) booster, the last of which occurred approximately 12½ hours into the mission. TDRS then deployed its antennas and solar panels, and separation from the IUS took place less than 45 minutes later. The TDRS network of satellites provides the vital communication link between Earth and low-orbiting spacecraft such as the Space Shuttle. Until the STS-43 deployment, there were three TDRS spacecraft on orbit above the equator: two were in the west position over the Pacific Ocean, southwest of Hawaii. TDRS-4 was in the east position over the northeast corner of Brazil. TDRS-B was lost in the Challenger accident in 1986. After STS-43, the two satellites in the west became on-orbit spares; TDRS-5, after activation, checkout and calibration, officially became the primary provider of services in the west location on October 7, 1991. It was stationed at 175° west longitude. Previously, orbiting spacecraft could communicate with Earth only when in sight of a ground tracking station – about 15 percent of each orbit. The TDRS network allows communication from 85% to 100% of an orbit, depending on the spacecraft's altitude. The crew was kept busy with the operation of varied experiments during the nine-day flight. The Space Station Heat Pipe Advanced Radiator Element (SHARE-II) experiment tested a natural cooling process for transferring thermal energy that could serve as a cooling system for Space Station Freedom. The Solid Surface Combustion Experiment (SSCE) provided some answers about how fire behaves in microgravity. The crew also activated other previously flown materials science experiments and participated in medical experiments in support of long-duration flights. One test showed that optical fibers could provide video and audio links between the flight deck and the payload bay. Crew members in space and flight controllers on the ground demonstrated their ingenuity when they adapted a camera part to replace one that had not been packed for the mission. The mission was also notable for being the first one to send an email from space. On August 9, 1991, astronauts Lucid and Adamson used AppleLink to write an email from a Macintosh Portable addressed to Marsha S. Ivins at Johnson Space Center. The message read:

Hello Earth! Greetings from the STS-43 crew. This is the first AppleLink from space. Having a GREAT time, wish you were here, ... send cryo and RCS! Hasta la vista, baby, ... we'll be back! The crew experienced some minor problems, none of them critical to the safety or success of the mission. A cooling system for Auxiliary Power Unit (APU 2) failed to activate during an on-orbit test. APU 2 is one of three redundant systems which provide hydraulic pressurization to orbiter steering systems during entry and landing. APU 2 was still available for use in landing. Atlantis landed on August 11, 1991, at 8:23:25 a.m. EDT, on Runway 15, at Kennedy Space Center.

Mission insignia According to the mission's official Press Kit, the STS-43 insignia portrays the evolution and continuity of the U.S. space program by highlighting thirty years of American crewed spaceflight experience, from Project Mercury to the Space Shuttle. The emergence of the shuttle Atlantis from the outlined configuration of the Mercury space capsule commemorates this special relationship. The energy and momentum of launch are conveyed by the gradations of blue which mark the shuttle's ascent from Earth to space. Once in Earth orbit, Atlantis' cargo bay opens to reveal the Tracking and Data Relay Satellite (TDRS) which appears in gold emphasis against the white wings of Atlantis and the stark blackness of space. As primary mission objective, the Tracking and Data Relay Satellite System (TDRSS) will enable almost continuous communication from Earth to space for future space shuttle missions. The stars on the insignia are arranged to suggest this mission's numerical designation, with four stars left of Atlantis and three to the right.

… excerpt ends here. Continue reading the full article.

Illustrations

Worked examples

Example 1 — a first encounter with STS-43

Start with the simplest possible case. Write down what STS-43 claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to STS-43 before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about STS-43 ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of STS-43

In research: STS-43 appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses STS-43 in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: STS-43 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Space Shuttle missions, Spacecraft launched in 1991, so understanding it makes those chapters shorter.
In everyday life: Look for STS-43 outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

How to study STS-43 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what STS-43 means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain STS-43 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is STS-43 in simple terms?

STS-43, the ninth mission for Space Shuttle Atlantis, was a nine-day mission whose primary goal was launching the TDRS-E satellite (TDRS-5). The flight also tested an advanced heatpipe radiator for potential use on the then-future space station and conducted a variety of medical and materials scien…

Why does STS-43 matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study STS-43?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on STS-43.