STS-120

Key takeaways

STS-120 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-120 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of STS-120 from memory before moving on to harder problems.

Reference excerpt

STS-120 was a Space Shuttle mission to the International Space Station (ISS) that launched on October 23, 2007, from the Kennedy Space Center, Florida. The mission is also referred to as ISS-10A by the ISS program. STS-120 delivered the Harmony module and reconfigured a portion of the station in preparation for future assembly missions. STS-120 was flown by Space Shuttle Discovery, and was the twenty-third Space Shuttle mission to the ISS. It was Discovery's 34th flight.

Crew

Crew notes

As commander of STS-120, Pamela Melroy became the second woman (after Eileen Collins) to command a Space Shuttle mission. Additionally, the Expedition 16 crew that received STS-120 was commanded by Peggy Whitson, the first female ISS commander. The flight of STS-120 thus became the first time two female mission commanders were in space at the same time.

Crew prior to the Space Shuttle Columbia disaster Prior to the Space Shuttle Columbia disaster, the original crew manifest for STS-120 was:

The STS-120 mission patch was designed by Michael Foreman before he was reassigned to STS-123.

Crew seat assignments

Mission payloads

Harmony (Node 2)

STS-120 delivered launch package 10A to the International Space Station (ISS). It consisted of the U.S. Harmony module (also known as Node 2), with four DC-to-DC Converter Unit (DDCU) racks and three Zero-g Storage Racks (ZSR) installed; a Power and Data Grapple Fixture (PDGF) for the station's robot arm, and a Shuttle Power Distribution Unit (SPDU). Harmony was manufactured for NASA by Thales Alenia Space in Turin, Italy, as part of an agreement between NASA and the European Space Agency and was the first pressurized habitable module delivered to the station since the Pirs docking compartment was installed in August 2001. Since STS-120 docked to the Pressurized Mating Adapter-2 (PMA-2) on the forward port of the Destiny module, installation of Harmony occurred in two stages: STS-120 installed Harmony to the port node of the Unity module. After Discovery undocked, the station's robotic arm detached PMA-2 from Destiny, and moved it to the forward port of Harmony. Following the relocation of PMA-2, the robotic arm was used to move Harmony from its initial position to its final position, on the forward port of Destiny. The final positioning of Harmony allowed for the later installation of the European Columbus and Japanese Kibō research modules, which were attached to the side ports of Harmony.

P6 relocation During STS-120, the P6 solar arrays were moved from the Z1 truss on top of Unity, to their final position at the port end of the truss.

Outreach STS-120 carried the signatures of over 500,000 students that participated in the 2007 Student Signatures in Space program, jointly sponsored by NASA and Lockheed Martin. In celebration of Space Day in May 2007, students from over 500 schools around the world signed giant posters. Their signatures were scanned onto a disk, and the disk was manifested on the STS-120 mission. Also during STS-120, the lightsaber used by actor Mark Hamill in the 1983 film Return of the Jedi was flown to the station and returned to Earth. Stowed on-board Discovery for the length of the mission, the prop was flown in honor of the 30th anniversary of the Star Wars franchise. On August 28, 2007, Chewbacca from the Star Wars films presented the lightsaber to NASA officials from Space Center Houston, in an official ceremony at Oakland International Airport. The lightsaber was then flown to Houston, where it was greeted by Stormtroopers. The lightsaber will be displayed at Space Center Houston.

Mission background At the time of the Columbia disaster, STS-120 was scheduled for early 2004. It was delayed repeatedly until October 23, 2007. NASA originally scheduled the launch for October 20, 2007, but due to the International Space Station program requirement, launch was delayed to October 23, 2007. In light of the small gouge to the underside of Endeavour that occurred on STS-118, in August 2007, NASA managers announced that they expected to add a fifth spacewalk to the STS-120 mission, designed to test a heat-shield repair tool. The repair technique was originally scheduled for a flight in 2008, but following STS-118, it was decided to move up the testing. The repair tool, called a TPS (thermal protection system) repair ablator dispenser (T-RAD), has never been tested in space, so the spacewalk would have allowed managers to evaluate its effectiveness in low gravity environments. During the course of the mission, issues with the S4 starboard Solar Alpha Rotary Joint (SARJ), and P6 Solar Array, deferred this test objective to a future mission. The mission marked:

151st NASA crewed spaceflight 120th Space Shuttle flight since STS-1 34th flight of Discovery 95th post-Challenger mission 7th post-Columbia mission

Mission timeline

Launch preparations

… excerpt ends here. Continue reading the full article.

Illustrations

Worked examples

Example 1 — a first encounter with STS-120

Start with the simplest possible case. Write down what STS-120 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-120 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-120 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-120

In research: STS-120 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-120 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-120 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Human spaceflights to the International Space Station, Space Shuttle missions, Spacecraft launched in 2007, so understanding it makes those chapters shorter.
In everyday life: Look for STS-120 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-120 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what STS-120 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-120 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is STS-120 in simple terms?

STS-120 was a Space Shuttle mission to the International Space Station (ISS) that launched on October 23, 2007, from the Kennedy Space Center, Florida. The mission is also referred to as ISS-10A by the ISS program.

Why does STS-120 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-120?

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-120.