Space Shuttle
Space Shuttle Discovery launches at the start of STS-120.
Fact sheet
Function	Manned partially re-usable launch and reentry system
Manufacturer	United Space Alliance: Thiokol/Boeing (SRBs) Lockheed Martin (Martin Marietta) - (ET) Rockwell International (orbiter)
Country of origin	United States of America
Size
Height	56.1 m (184 ft (56 m))
Diameter	8.7 m (28.5 ft (8.7 m))
Mass	2,029,203 kg (4,474,574 lb)
Stages	2
Capacity
Payload to LEO	24,400 kg (53,600 lb)
Payload to GTO	3,810 kg (8,390 lb)
Launch History
Status	Active
Launch sites	LC-39, Kennedy Space Center SLC-6, Vandenberg AFB (unused)
Total launches	121
Successes	119
Failures	2
Maiden flight	April 12, 1981
Notable payloads	International Space Station components Hubble Space Telescope Galileo Magellan Chandra X-ray Observatory Compton Gamma Ray Observatory
Boosters (Stage 0) - Solid Rocket Boosters
No boosters	2
Engines	1 solid
Thrust	2,800,000 lbf each, sea level liftoff (12.5 MN)
Specific impulse	269 s
Burn time	124 s
Fuel	solid
First Stage - External Tank
Engines	(none) (3 SSMEs located on Orbiter)
Thrust	53.4 kN (12,000 lbf) combined total, sea level liftoff (5.25 MN)
Specific impulse	455 s
Burn time	480 s
Fuel	LOX/LH2
Second Stage - Orbiter
Engines	2 OME
Thrust	53.4 kN combined total vacuum thrust (12,000 lbf)
Specific impulse	316 s
Burn time	1250 s
Fuel	MMH/N2O4

Space Shuttle program insignia

NASA's Space Shuttle, officially called the Space Transportation System (STS), is the spacecraft currently used by the United States government for its human spaceflight missions. At launch, it consists of a rust-colored external tank (ET), two white, slender Solid Rocket Boosters (SRBs), and the orbiter, a winged spaceplane which is the space shuttle in the narrow sense. This article is about the NASA Space Shuttle program. ... The Buran spacecraft, serial number 11F35 K1, was the only fully completed and operational space shuttle from the Soviet Unions Buran program. ... Image File history File links Metadata Size of this preview: 391 × 599 pixelsFull resolution (1000 × 1533 pixels, file size: 946 KB, MIME type: image/jpeg) Other versions High resolution File historyClick on a date/time to view the file as it appeared at that time. ... Space Shuttle Discovery (Orbiter Vehicle Designation: OV-103) is one of the three currently operational orbiters in the Space Shuttle fleet of NASA, the space agency of the United States. ... STS-120 is the current Space Shuttle mission to the International Space Station (ISS), that launched on October 23, 2007. ... Headquartered in Houston, Texas, United Space Alliance (USA) is one of the world’s leading space operations companies. ... A Trident C-4 FBM launches and fires its Thiokol solid rocket first stage Thiokol (variously Thiokol Chemical Company, Morton-Thiokol Inc. ... The Boeing Company (NYSE: BA, TYO: 7661) is a major aerospace and defense corporation, originally founded by William Edward Boeing. ... Lockheed/BAE/Northrop F-35 Lockheed Trident missile C-130 Hercules; in production since the 1950s, now as the C-130J Lockheed Martin (NYSE: LMT) is an aerospace manufacturer formed in 1995 by the merger of Lockheed Corporation with Martin Marietta. ... Martin Marietta Corporation was founded in 1961 through the merger of The Martin Company and American-Marietta Corporation. ... Boeing Integrated Defense Systems (Boeing IDS), based in St. ... Motto: (traditional) In God We Trust (official, 1956–present) Anthem: The Star-Spangled Banner Capital Washington, D.C. Largest city New York City Official language(s) None at the federal level; English de facto Government Federal Republic  - President George W. Bush (R)  - Vice President Dick Cheney (R) Independence - Declared - Recognized... Look up pound in Wiktionary, the free dictionary. ... In military aircraft or space exploration, the payload is the carrying capacity of an aircraft or space ship, including as cargo, munitions, scientific instruments or experiments, or external fuel, although internal fuel is usually not included. ... A low Earth orbit (LEO) is an orbit in which objects such as satellites are below intermediate circular orbit (ICO) and far below geostationary orbit, but typically around 350 - 1400 km above the Earths surface. ... A geostationary transfer orbit (GTO) is a Hohmann transfer orbit around the Earth between a low Earth orbit (LEO) and a geostationary orbit (GEO). ... Launch Complex 39 is a large site and a collection of facilities at the John F. Kennedy Space Center on Merritt Island in Florida, USA, originally built for the Apollo program, and later modified to support Space Shuttle operations. ... Merritt Island and Kennedy Space Center (shown in white). ... First launch of a Boeing Delta IV Medium+ (4,2) from SLC-6 on June 27, 2006 (Official photo by Thom Baur for Boeing) Space Launch Complex-6 (SLC-6, nicknamed Slick Six) at Vandenberg Air Force Base in California was a launch pad and support area designed for the... Boeing Delta 4 Medium+ (4,2) lifts off from Space Launch Complex Six (SLC-6) at Vandenberg AFB, California (Official photo by Thom Baur for the Boeing Company) Vandenberg Air Force Base (IATA: VBG, ICAO: KVBG) is a United States military installation with a spaceport, in Santa Barbara County, California... is the 102nd day of the year (103rd in leap years) in the Gregorian calendar. ... AUGUST 25 1981 US Marine Sean Vance is Born on the 25th of August {ear nav|1981}} Year 1981 (MCMLXXXI) was a common year starting on Thursday (link displays the 1981 Gregorian calendar). ... ISS redirects here. ... The Hubble Space Telescope (HST; also known colloquially as the Hubble or just Hubble) is a space telescope that was carried into Earth orbit by the Space Shuttle in April 1990. ... Galileo is prepared for mating with the IUS booster Galileo being deployed after being launched by the Space Shuttle Atlantis on the STS-34 mission Galileo was an unmanned spacecraft sent by NASA to study the planet Jupiter and its moons. ... Magellan spacecraft at Kennedy Space Center The Magellan spacecraft carried out a mission from 1989-1994, orbiting Venus from 1990-1994. ... The Chandra X-ray Observatory is a satellite launched on STS-93 by NASA on July 23, 1999. ... Illustration of CGRO The Compton Gamma Ray Observatory(CGRO) was the second of the NASA Great Observatories to be launched to space, following the Hubble Space Telescope. ... The Space Shuttle Solid Rocket Booster (SRB) is the rocket that provides 83% of liftoff thrust for the Space Shuttle. ... The Space Shuttle Columbia is initially launched with the help of solid-fuel boosters A solid rocket or a solid fuel rocket is a rocket with a motor that uses solid propellants (fuel/oxidizer). ... A pound or pound-force (abbreviations: lb, lbf, or lbf) is a unit of force. ... For considerations of sea level change, in particular rise associated with possible global warming, see sea level rise. ... In physics, the newton (symbol: N) is the SI unit of force, named after Sir Isaac Newton in recognition of his work on classical mechanics. ... Specific impulse (usually abbreviated Isp) is a way to describe the efficiency of rocket and jet engines. ... The Space Shuttle External Tank (ET) on its way to the Vehicle Assembly Building. ... Space Shuttle Main Engine cluster The Space Shuttle Main Engines (SSMEs) are the three main engines on the Space Shuttle orbiter. ... Specific impulse (usually abbreviated Isp) is a way to describe the efficiency of rocket and jet engines. ... This article does not cite any references or sources. ... Liquid hydrogen is the liquid state of the element hydrogen. ... This article does not cite any references or sources. ... An OMS pod detached from a Shuttle for maintenance. ... Specific impulse (usually abbreviated Isp) is a way to describe the efficiency of rocket and jet engines. ... Monomethylhydrazine (MMH) is a volatile hydrazine with the chemical formula CH3N2H3. ... Nitrogen tetroxide (or dinitrogen tetroxide) is the chemical compound N2O4. ... Image File history File links This is a lossless scalable vector image. ... Image File history File links This is a lossless scalable vector image. ... For other uses, see NASA (disambiguation). ... The Space Shuttle Discovery as seen from the International Space Station. ... Edward White on a spacewalk during the Gemini 4 mission. ... A Space Shuttle External Tank (ET) on its way to the Vehicle Assembly Building. ... The Space Shuttle Solid Rocket Booster (SRB) is the rocket that provides 83% of liftoff thrust for the Space Shuttle. ... This article does not cite any references or sources. ... A spaceplane is a rocket plane designed to pass the edge of space. ...

The orbiter carries astronauts and payload such as satellites or space station parts into low earth orbit, into the Earth's upper atmosphere or thermosphere.^[1] Usually, five to seven crew members ride in the orbiter. The payload capacity is 22,700 kg (50,000 lb). When the orbiter's mission is complete it fires its Orbital Maneuvering System (OMS) thrusters to drop out of orbit and re-enters the lower atmosphere.^[1] During the descent and landing, the shuttle orbiter acts as a glider, and makes a completely unpowered ("dead stick") landing. For other uses, see Astronaut (disambiguation). ... A low Earth orbit (LEO) is an orbit in which objects such as satellites are below intermediate circular orbit (ICO) and far below geostationary orbit, but typically around 350 - 1400 km above the Earths surface. ... The thermosphere is the layer of the earths atmosphere directly above the mesosphere and directly below the exosphere. ... An OMS pod detached from a Shuttle for maintenance. ... “Reentry” redirects here. ... For other uses, see Glider (disambiguation). ... A deadstick landing or forced landing occurs when an aircraft loses all of its propulsive power and is forced to land. ...

Description

The shuttle is the first orbital spacecraft designed for partial reusability. It carries payloads to low Earth orbit, provides crew rotation for the International Space Station (ISS), and performs servicing missions. The orbiter can also recover satellites and other payloads from orbit and return them to Earth, but this capacity has not been used often. However, it has been used to return large payloads from the ISS to Earth, as the Russian Soyuz spacecraft has limited capacity for return payloads. Each Shuttle was designed for a projected lifespan of 100 launches or 10 years operational life. The man responsible for the design of the STS was Maxime Faget, who had also overseen the Mercury, Gemini and Apollo spacecraft designs. The crucial factor in the size and shape of the Shuttle Orbiter was the requirement that it be able to accommodate the largest planned spy satellites, and have the cross-range recovery range to meet classified USAF missions requirement for a one-around abort for a polar launch. Factors involved in opting for 'reusable' solid rockets and an expendable fuel tank included the desire of the Pentagon to obtain a high-capacity payload vehicle for satellite deployment, and the desire of the Nixon administration to reduce the costs of space exploration by developing a spacecraft with reusable components. The Space Shuttle Discovery as seen from the International Space Station. ... A reusable launch system (or RLV: reusable launch vehicle) is a launch vehicle which is capable of launching into space more than once. ... A low Earth orbit (LEO) is an orbit in which objects such as satellites are below intermediate circular orbit (ICO) and far below geostationary orbit, but typically around 350 - 1400 km above the Earths surface. ... ISS redirects here. ... This article is about artificial satellites. ... This article is about Earth as a planet. ... Soyuz (Russian: Союз, pronounced sah-YOUS, meaning union) is a series of spacecraft designed by Sergey Korolyov for the Soviet Unions space program. ... Max Faget Maxime Max A. Faget (August 26, 1921 – October 9, 2004) was an American engineer. ...

Six air-worthy shuttles have been built; the first orbiter, Enterprise, was not built for space flight, and was used only for testing purposes. Five space-worthy orbiters were built: Columbia, Challenger, Discovery, Atlantis, and Endeavour. Challenger disintegrated 73 seconds after launch in 1986, and Endeavour was built as a replacement. Columbia broke apart during re-entry in 2003. The Space Shuttle Enterprise (NASA Orbiter Vehicle Designation: OV-101) was the first Space Shuttle built for NASA. It was constructed without engines or a functional heat shield, and was therefore not capable of space operations; its purpose was to perform test flights in the atmosphere. ... Space Shuttle Columbia (NASA Orbiter Vehicle Designation: OV-102) was the first spaceworthy space shuttle in NASAs orbital fleet. ... Space Shuttle Challenger (NASA Orbiter Vehicle Designation: OV-099) was NASAs second Space Shuttle orbiter to be put into service, Columbia being the first. ... Space Shuttle Discovery (Orbiter Vehicle Designation: OV-103) is one of the three currently operational orbiters in the Space Shuttle fleet of NASA, the space agency of the United States. ... Space Shuttle Orbiter Atlantis (NASA Orbiter Vehicle Designation: OV-104) is one of the fleet of space shuttles belonging to the U.S. National Aeronautics and Space Administration (NASA). ... Space Shuttle Orbiter Endeavour (NASA Orbiter Vehicle Designation: OV-105), is the fifth and final operational NASA space shuttle. ... For further information about Challengers mission and crew, see STS-51-L. The iconic image of Space Shuttle Challengers smoke plume after its breakup 73 seconds after launch. ... For further information about Columbias mission and crew, see STS-107. ...

First launched in 1981, NASA has announced that the Space Shuttle would be retired in 2010, and from 2014 on, would be replaced by Orion, a new vehicle that is designed to take humans to the Moon and beyond along with its partner rockets, the Ares I and Ares V Rockets; however, since Orion is meant primarily for manned space flights, ESA's Automated Transfer Vehicle, with its 7,667 kg payload, has been suggested as an alternative for tasks like supplying space stations. Orion is a spacecraft currently under development by the United States National Aeronautics and Space Administration (NASA). ... This article is about Earths moon. ... This article is about the European Space Agency. ... ATV vs Apollo vs Progress The Automated Transfer Vehicle or ATV is an expendable, unmanned resupply spacecraft developed by the European Space Agency (ESA). ... Look up payload in Wiktionary, the free dictionary. ... The International Space Station in 2007 A space station is an artificial structure designed for humans to live in outer space. ...

Each Space Shuttle is a partially reusable launch system that is composed of three main assemblies: the reusable Orbiter Vehicle (OV), the expendable external tank (ET), and the two partially-reusable solid rocket boosters (SRBs). The tank and boosters are jettisoned during ascent; only the orbiter goes into orbit. The vehicle is launched vertically like a conventional rocket, and the orbiter glides to a horizontal landing, after which it is refurbished for reuse. A reusable launch system (or RLV: reusable launch vehicle) is a launch vehicle which is capable of launching into space more than once. ... This article does not cite any references or sources. ... A Space Shuttle External Tank (ET) on its way to the Vehicle Assembly Building. ... The Space Shuttle Solid Rocket Booster (SRB) is the rocket that provides 83% of liftoff thrust for the Space Shuttle. ...

At times, the orbiter itself is referred to as the space shuttle. Technically, this is a misnomer, as the actual "Space Transportation System" (space shuttle) is the combination of the orbiter, the external tank (ET), and the two partially-reusable solid rocket boosters. Combined, these are referred to as the "Stack". A Space Shuttle External Tank (ET) on its way to the Vehicle Assembly Building. ... The Space Shuttle Solid Rocket Booster (SRB) is the rocket that provides 83% of liftoff thrust for the Space Shuttle. ...

Orbiter vehicle

Main article: Space Shuttle Orbiter

The orbiter resembles an aircraft with double-delta wings, swept 81° at the inner leading edge, and 45° at the outer leading edge. Its vertical stabilizer's leading edge is swept back at a 50° angle. The four elevons, mounted at the trailing edge of the wings, and the rudder/speed brake, attached at the trailing edge of the stabilizer, with the body flap, control the orbiter during descent and landing. The orbiter has a large payload bay measuring 15 feet (4.6 m) by 60 feet (18.3 m) comprising most of the fuselage. This article does not cite any references or sources. ... The delta-wing is a wing planform in the form of a triangle, named after the Greek uppercase delta (letter) which is a triangle (Δ). Its use in the so called tailless delta, i. ... Elevons at the wing trailing edge are used for pitch and roll control of the F-117A Nighthawk ( best seen by clicking on the picture). ... Stern-mounted steering oar of an Egyptian riverboat depicted in the Tomb of Menna (c. ... The fuselage can be short, and seemingly unaerodynamic, as in this Christen Eagle 2 The fuselage (from the French fuselé spindle-shaped) is an aircrafts main body section that holds crew and passengers or cargo. ...

Three Space Shuttle Main Engines (SSMEs) are mounted on the orbiter's aft fuselage in a triangular pattern. The three engines can swivel 10.5 degrees up and down, and 8.5 degrees from side to side during ascent to change the direction of their thrust and steer the shuttle as well as push. The orbiter structure is made primarily from aluminum alloy, although the engine thrust structure is made from titanium (alloy). Space Shuttle Main Engine block The Space Shuttle orbiter has three main engines. ... Aluminum redirects here. ... Steel is a metal alloy whose major component is iron, with carbon content between 0. ... General Name, symbol, number titanium, Ti, 22 Chemical series transition metals Group, period, block 4, 4, d Appearance silvery grey-white metallic Standard atomic weight 47. ...

Solid Rocket Boosters

Main article: Space Shuttle Solid Rocket Booster

Two solid rocket boosters (SRBs) each provide 12.5 million Newtons (2.8 million lbf) of thrust at liftoff, which is 83% of the total thrust needed for liftoff. The SRBs are jettisoned two minutes after launch at a height of about 45.7 km (150,000 feet), and then deploy parachutes and land in the ocean to be recovered.^[2] The SRB cases are made of steel about 1.3 cm (½ inch) thick.^[3] The Space Shuttle Solid Rocket Booster (SRB) is the rocket that provides 83% of liftoff thrust for the Space Shuttle. ...

Flight systems

Early shuttle missions took along the GRiD Compass, arguably one of the first laptop computers. The Compass sold poorly, as it cost at least US$8000, but offered unmatched performance for its weight and size.^[4] NASA was one of its main customers.^[5] A GRiD Compass on display at the U.S. Space & Rocket Center in Huntsville, Alabama The GRiD Compass 1100 was arguably the first laptop computer, introduced in April 1982. ... An ultraportable IBM X31 with 12 screen on an IBM T43 Thin & Light laptop with a 14 screen A laptop computer, or simply laptop (also notebook computer, notebook and notepad) is a small mobile computer, typically weighing 3-12 pounds (around 1. ... USD redirects here. ...

The shuttle was one of the earliest craft to use a computerized fly-by-wire digital flight control system. This means no mechanical or hydraulic linkages connect the pilot's control stick to the control surfaces or reaction control system thrusters. A flight control system consists of the flight control surfaces, the respective cockpit controls, connecting linkage, and necessary operating mechanisms to control aircraft in flight The basic fundamentals of aircraft controls has been explained in aeronautics. ... A flight control system consists of the flight control surfaces, the respective cockpit controls, connecting linkage, and necessary operating mechanisms to control aircraft in flight The fundamentals of aircraft controls has been explained in aeronautics. ... A reaction control system (abbreviated RCS) is a subsystem of a spacecraft. ...

A primary concern with digital fly-by-wire systems is reliability. Much research went into the shuttle computer system. The shuttle uses five identical redundant IBM 32-bit general purpose computers (GPCs), model AP-101, constituting a type of embedded system. Four computers run specialized software called the Primary Avionics Software System (PASS). A fifth backup computer runs separate software called the Backup Flight System (BFS). Collectively they are called the Data Processing System (DPS).^[6][7] The IBM AP-101 is an avionics computer, used most notably in the U.S. Space Shuttle, but also in the B-52 and F-15, among others. ... A router, an example of an embedded system. ...

The design goal of the shuttle's DPS is fail operational/fail safe reliability. After a single failure, the shuttle can still continue the mission. After two failures, it can still land safely.

The four general-purpose computers operate essentially in lockstep, checking each other. If one computer fails, the three functioning computers "vote" it out of the system. This isolates it from vehicle control. If a second computer of the three remaining fails, the two functioning computers vote it out. In the rare case of two out of four computers simultaneously failing (a two-two split), one group is picked at random.

Atlantis deploys landing gear before landing on a selected runway just like a common aircraft.

The Backup Flight System (BFS) is separately developed software running on the fifth computer, used only if the entire four-computer primary system fails. The BFS was created because although the four primary computers are hardware redundant, they all run the same software, so a generic software problem could crash all of them. Embedded system avionic software is developed under totally different conditions from public commercial software, the number of code lines is tiny compared to a public commercial software, changes are only made infrequently and with extensive testing, and many programming and test personnel work on the small amount of computer code. However in theory it can still fail, and the BFS exists for that contingency. And while BFS will run in parallel with PASS, to date, BFS has never been engaged to take over control from PASS during any shuttle mission. Main and nosewheel undercarriage of a Qatar Airways Airbus A330 The undercarriage or landing gear is equipment which supports an aircraft when it is not flying. ... A router, an example of an embedded system. ... Avionics is a portmanteau which literally means aviation electronics. ...

The software for the shuttle computers is written in a high-level language called HAL/S, somewhat similar to PL/I. It is specifically designed for a real time embedded system environment. HAL/S is a real-time aerospace programming language, best known for its use in the Space Shuttle program. ... PL/I (Programming Language One, pronounced pee el one) is an imperative computer programming language designed for scientific, engineering, and business applications. ... Realtime redirects here. ... A router, an example of an embedded system. ...

The IBM AP-101 computers originally had about 424 kilobytes of magnetic core memory each. The CPU could process about 400,000 instructions per second. They have no hard disk drive, and load software from magnetic tape cartridges. A 16×16 cm area core memory plane of 128×128 bits, i. ...

In 1990, the original computers were replaced with an upgraded model AP-101S, which has about 2.5 times the memory capacity (about 1 megabyte) and three times the processor speed (about 1.2 million instructions per second). The memory was changed from magnetic core to semiconductor with battery backup.

Typography and graphic design

The typeface used on the Space Shuttle Orbiter is Helvetica.^[8] On the front lower corner of the cargo bay doors is the name of the orbiter, on the back lower corner of the cargo bay is the NASA 'Worm' logo. Below the NASA logo is the text 'United States' with a flag of the United States. Another United States flag appears on the right wing. “Font” redirects here. ... This article is about the typeface Helvetica. ... The National Aeronautics and Space Administration (NASA) logo has three official designs, although one of them (the worm) has been retired from official use since 1992. ... Union Jack. ...

Upgrades

During STS-101, Atlantis was the first shuttle to fly with a glass cockpit.

Internally, the shuttle remains largely similar to the original design, with the exception of the improved avionics computers. In addition to the computer upgrades, the original vector graphics monochrome cockpit displays were replaced with modern full-color, flat-panel display screens, similar to those of contemporary airliners like the Airbus A380 and Boeing 777. This is called a glass cockpit. In the Apollo-Soyuz Test Project traditional, programmable calculators are carried as well (originally the HP-41C). With the coming of the ISS, the orbiter's internal airlocks have been replaced with external docking systems to allow for a greater amount of cargo to be stored on the shuttle's mid-deck during station resupply missions. Image File history File links STSCPanel. ... Image File history File links STSCPanel. ... This is a mission of the United States Space Shuttle // Crew James D. Halsell, Jr. ... Space Shuttle Orbiter Atlantis (NASA Orbiter Vehicle Designation: OV-104) is one of the fleet of space shuttles belonging to the U.S. National Aeronautics and Space Administration (NASA). ... This article does not cite any references or sources. ... Example showing effect of vector graphics versus raster graphics. ... The Airbus A380 is a double-deck, wide-body, four-engine airliner manufactured by the European corporation Airbus, an EADS subsidiary. ... The Boeing 777 is a long-range, wide-body twin-engine airliner built by Boeing Commercial Airplanes. ... This article does not cite any references or sources. ... The Apollo-Soyuz Test Project was the first joint flight of the U.S. and Soviet space programs. ... The HP-41 series are programmable, expandable, handheld RPN calculators made by Hewlett-Packard from 1979 to 1990. ...

The Space Shuttle Main Engines (SSMEs) have had several improvements to enhance reliability and power. This explains phrases such as "Main engines throttling up to 104%." This does not mean the engines are being run over a safe limit. The 100% figure is the original specified power level. During the lengthy development program, Rocketdyne determined the engine was capable of safe reliable operation at 104% of the originally specified thrust. They could have rescaled the output number, saying in essence 104% is now 100%. To clarify this would have required revising much previous documentation and software, so the 104% number was retained. SSME upgrades are denoted as "block numbers", such as block I, block II, and block IIA. The upgrades have improved engine reliability, maintainability and performance. The 109% thrust level was finally reached in flight hardware with the Block II engines in 2001. The normal maximum throttle is 104%, with 106% and 109% available for abort emergencies. Space Shuttle Main Engine cluster The Space Shuttle Main Engines (SSMEs) are the three main engines on the Space Shuttle orbiter. ... F-1 rocket engine Rocketdyne is a United States company that designs and produces rocket engines that use liquid propellants. ... A Space Shuttle abort is an emergency procedure due to equipment failure on NASAs Space Shuttle, most commonly during ascent. ...

For the first two missions, STS-1 and STS-2, the external tank was painted white to protect the insulation that covers much of the tank, but improvements and testing showed that it was not required. The weight saved by not painting the tank results in an increase in payload capability to orbit.^[9] Additional weight was saved by removing some of the internal "stringers" in the hydrogen tank that proved unnecessary. The resulting "light-weight external tank" has been used on the vast majority of shuttle missions. STS-91 saw the first flight of the "super light-weight external tank". This version of the tank is made of the 2195 aluminum-lithium alloy. It weighs 3.4 tonnes (7,500 lb) less than the last run of lightweight tanks. As the shuttle cannot fly unmanned, each of these improvements has been "tested" on operational flights. STS-1 is also an abbreviation for Synchronous Transport Signal (level)-1 in the SONET hierarchy. ... STS-2 was a space shuttle mission by NASA using the Space Shuttle Columbia, launched November 12, 1981. ... A Space Shuttle External Tank (ET) on its way to the Vehicle Assembly Building. ... This is a mission of the United States Space Shuttle // Crew Charles J. Precourt (4), Commander Dominic L. Pudwill Gorie (1), Pilot Wendy B. Lawrence (3), Mission Specialist Franklin R. Chang-Diaz (6), Mission Specialist Janet L. Kavandi (1), Mission Specialist Valery Victorovitch Ryumin (4), Mission Specialist - Russia Landed and...

The SRBs (Solid Rocket Boosters) have undergone improvements as well. Design engineers added a third O-ring seal to the joints between the segments after the Space Shuttle Challenger disaster. Typical O-ring and application An O-ring is a loop of elastomer with a round (o-shaped) cross-section used as a mechanical seal. ... For further information about Challengers mission and crew, see STS-51-L. The iconic image of Space Shuttle Challengers smoke plume after its breakup 73 seconds after launch. ...

The three nozzles of the Main Engine cluster with the two Orbital Maneuvering System (OMS) pods, and the vertical stabilizer above.

Several other SRB improvements were planned in order to improve performance and safety, but never came to be. These culminated in the considerably simpler, lower cost, probably safer and better performing Advanced Solid Rocket Booster. These rockets entered production in the early to mid-1990s to support the Space Station, but were later canceled to save money after the expenditure of $2.2 billion.^[10] The loss of the ASRB program resulted in the development of the Super LightWeight external Tank (SLWT), which provides some of the increased payload capability, while not providing any of the safety improvements. In addition, the Air Force developed their own much lighter single-piece SRB design using a filament-wound system, but this too was cancelled. Download high resolution version (1752x2617, 850 KB)Space shuttle main engine block This article contains material and/or images that originally came from a NASA website. ... Download high resolution version (1752x2617, 850 KB)Space shuttle main engine block This article contains material and/or images that originally came from a NASA website. ... Space Shuttle Main Engine cluster The Space Shuttle Main Engines (SSMEs) are the three main engines on the Space Shuttle orbiter. ... An OMS pod detached from a Shuttle for maintenance. ... The vertical stabilizer or fin of an aircraft is found on its tail, generally pointing straight upward. ...

STS-70 was delayed in 1995, when woodpeckers bored holes in the foam insulation of Discovery's external tank. Since then, NASA has installed commercial plastic owl decoys and inflatable owl balloons which must be removed prior to launch.^[11] The delicate nature of the foam insulation has been the cause of damage to the Thermal Protection System, the tile heat shield and heat wrap of the orbiter, during recent launches. NASA remains confident that this damage, while linked to the Space Shuttle Columbia disaster on February 1, 2003, will not jeopardize the objective of NASA to complete the International Space Station (ISS) in the projected time allotted. The STS-70 is a Space Shuttle program mission. ... Genera Melanerpes Sphyrapicus Xiphidiopicus Dendropicos Dendrocopos Picoides Veniliornis Campethera Geocolaptes Dinopium Meiglyptes Hemicircus Micropternus Picus Mulleripicus Dryocopus Celeus Piculus Colaptes Campephilus Chrysocolaptes Reinwardtipicus Blythipicus Gecinulus Sapheopipo For other uses, see Woodpecker (disambiguation). ... The space shuttle thermal protection system (TPS) is the barrier that protects the space shuttle orbiter during the searing 1649 °C (3000 °F) heat of atmospheric reentry. ... For further information about Columbias mission and crew, see STS-107. ... is the 32nd day of the year in the Gregorian calendar. ... Year 2003 (MMIII) was a common year starting on Wednesday of the Gregorian calendar. ... ISS redirects here. ...

A cargo-only, unmanned variant of the shuttle has been variously proposed, and rejected since the 1980s. It was called the Shuttle-C, and would have traded re-usability for cargo capability, with large potential savings from reusing technology developed for the space shuttle. An artists conception of a Shuttle-C launching at night. ...

On the first four shuttle missions, astronauts wore modified U.S. Air Force high-altitude full-pressure suits, which included a full-pressure helmet during ascent and descent. From the fifth flight, STS-5, until the loss of Challenger, one-piece light blue nomex flight suits and partial-pressure helmets were worn. A less-bulky, partial-pressure version of the high-altitude pressure suits with a helmet was reinstated when shuttle flights resumed in 1988. The LES ended its service life in late 1995, and was replaced by the full-pressure Advanced Crew Escape Suit (ACES), which resembles the Gemini space suit worn in the mid-1960s. STS-5 was a space shuttle mission by NASA using the Space Shuttle Columbia, launched November 11, 1982. ... For further information about Challengers mission and crew, see STS-51-L. The iconic image of Space Shuttle Challengers smoke plume after its breakup 73 seconds after launch. ... NOMEX® is the brand name of a flame retardant meta-aramid material marketed and first discovered by DuPont in the 1970s. ... NASA portrait of Russian Cosmonaut Yuri Lonchakov, wearing an ACES suit. ... This article or section does not adequately cite its references or sources. ...

To extend the duration that orbiters can stay docked at the ISS, the Station-to-Shuttle Power Transfer System (SSPTS) was installed. The SSPTS allows these orbiters to use power provided by the ISS to preserve their consumables. The SSPTS was first used successfully on STS-118. Station-to-Shuttle Power Transfer System (SSPTS pronounced spits) allows a docked Space Shuttle to make use of power provided by the International Space Stations solar arrays. ... STS-118 was a Space Shuttle mission to the International Space Station (ISS) flown by Space Shuttle Endeavour. ...

Technical data

Space Shuttle Atlantis transported by a Boeing 747 Shuttle Carrier Aircraft (SCA), 1998 (NASA).

Space Shuttle Endeavour being transported by a Boeing 747.

Space Shuttle Orbiter and Soyuz-TM (drawn to scale).

An overhead view of Atlantis as it sits atop the Mobile Launcher Platform (MLP) before STS-79. Two Tail Service Masts (TSMs) to either side of the orbiter's tail provide umbilical connections for propellant loading and electrical power.

Water is released onto the mobile launcher platform on Launch Pad 39A at the start of a rare sound suppression system test in 2004. During launch, 300,000 US gallons (1,100 m³) are poured onto the pad in only 41 seconds.

Orbiter specifications^[12] (for Endeavour, OV-105) Download high resolution version (3030x2360, 4888 KB) Wikipedia does not have an article with this exact name. ... Download high resolution version (3030x2360, 4888 KB) Wikipedia does not have an article with this exact name. ... Space Shuttle Orbiter Atlantis (NASA Orbiter Vehicle Designation: OV-104) is one of the fleet of space shuttles belonging to the U.S. National Aeronautics and Space Administration (NASA). ... The Boeing 747, sometimes nicknamed the Jumbo Jet,[4][5] is a long-haul, widebody commercial airliner manufactured by Boeing in the United States. ... Discovery leaves Edwards AFB on the back of a Shuttle Carrier enroute to Kennedy Space Center in Florida Space Shuttle Columbia atop Shuttle Carrier Aircraft (SCA) N905NA, after the successful STS-32 mission, fly by the Vehicle Assembly Building (VAB) at Kennedy Space Center (KSC). ... Image File history File links Download high-resolution version (1050x750, 179 KB) Space Shuttle Transit Found on this website: http://www. ... Image File history File links Download high-resolution version (1050x750, 179 KB) Space Shuttle Transit Found on this website: http://www. ... Space Shuttle Orbiter Endeavour (NASA Orbiter Vehicle Designation: OV-105), is the fifth and final operational NASA space shuttle. ... The Boeing 747, sometimes nicknamed the Jumbo Jet,[4][5] is a long-haul, widebody commercial airliner manufactured by Boeing in the United States. ... Image File history File links Size of this preview: 679 × 600 pixelsFull resolution (2783 × 2459 pixel, file size: 233 KB, MIME type: image/png) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Soyuz spacecraft ... Image File history File links Size of this preview: 679 × 600 pixelsFull resolution (2783 × 2459 pixel, file size: 233 KB, MIME type: image/png) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Soyuz spacecraft ... Soyuz TMA-6 spacecraft approaching International Space Station Soyuz 19 spacecraft as seen from Apollo CM Soyuz spacecraft of the Apollo Soyuz Test Project (ASTP) Early 7K-OK Soyuz at National Space Centre, Leicester, England Soyuz (Союз, union) is a series of spacecraft designed by Sergey Korolev for the Soviet Union... A Crawler-Transporter carries a MLP atop. ... STS-79 is a Space Shuttle program mission. ... Image File history File links MainSPStest. ... Image File history File links MainSPStest. ...

• Length: 37.24 m (122.17 ft)
• Wingspan: 23.79 m (78.06 ft)
• Height: 58.58 ft (17.86 m)
• Empty weight: 68,585 kg (151,205 lb)
• Gross Liftoff Weight: 109,000 kg (240,000 lb)
• Maximum Landing Weight: 104,000 kg (230,000 lb)
• Main engines: Three Rocketdyne Block IIA SSMEs, each with a sea level thrust of 1.75 meganewtons (MN) (393,800 pounds-force (lbf))
• Maximum payload: 25,061 kilograms (55,250 lb)
• Payload bay dimensions: 4.6 m (15 ft) by 18 m (59 ft)
• Operational altitude: 100 to 520 nmi (185 to 960 km)
• Speed: 7,743 m/s (27,875 km/h, 25,404 ft/s, 17,321 mi/h)
• Crossrange: 2,009 km (1,085 nmi)
• Crew: Varies. The earliest shuttle flights had the minimum crew of two; many later missions a crew of five. Today, typically seven people fly (commander, pilot, several mission specialists, and rarely a flight engineer). On two occasions, eight astronauts have flown (STS-61-A, STS-71). Eleven people could be accommodated in an emergency mission (see STS-3xx).

External tank specifications (for SLWT) Thrust is a reaction force described quantitatively by Newtons Second and Third Laws. ... The pound-force is a non-SI unit of force or weight (properly abbreviated lbf or lbf). The pound-force is equal to a mass of one pound multiplied by the standard acceleration due to gravity on Earth (which is defined as exactly 9. ... A nautical mile or sea mile is a unit of length. ... Commander is a military rank which is also sometimes used as a military title depending on the individual customs of a given military service. ... For other uses, see Aviator (disambiguation). ... A Mission Specialist (MS) is a position held by certain NASA astronauts for the Space Shuttle program. ... In aviation, a flight engineer (also referred to as systems operator ) is a member of the aircrew of an aircraft who is responsible for checking the aircraft before and after each flight, and for monitoring aircraft systems during flight. ... STS-61-A was the 22nd Space Shuttle mission. ... STS-71 was a Space Shuttle program mission. ... Space shuttle missions designated STS-3xx (officially called Launch On Need missions) are rescue missions which would be mounted to rescue the crew of a Space Shuttle if their vehicle was damaged and deemed unable to make a successful reentry. ...

• Length: 46.9 m (153.8 ft)
• Diameter: 8.4 m (27.6 ft)
• Propellant volume: 2,025 m³ (535,000 US gal)
• Empty Weight: 26,535 kg (58,500 lb)
• Gross Liftoff Weight: 756,000 kg (1,667,000 lb)

Solid Rocket Booster Specifications The cubic meter (symbol m³) is the SI derived unit of volume. ... The gallon (abbreviation: gal) is a unit of volume. ...

• Length: 45.6 m (149.6 ft)
• Diameter: 3.7 m (12.14 ft)
• Empty Weight (per booster): 63,272 kg (139,491 lb)
• Gross Liftoff Weight (per booster): 590,000 kg (1.3 million lb)
• Thrust (sea level, liftoff): 12.5 MN (2.8 million lbf)

System Stack Specifications

• Height: 56 m (183.7 ft)
• Gross Liftoff Weight: 2 million kg (4.5 million lb)
• Total Liftoff Thrust: 30.16 MN (6.781 million lbf)

Mission profile

Launch

All Space Shuttle missions are launched from Kennedy Space Center (KSC). The shuttle will not be launched under conditions where it could be struck by lightning. Aircraft are often struck by lightning with no adverse effects because the electricity of the strike is dissipated through its conductive structure and the aircraft is not electrically grounded. Like most jet airliners, the shuttle is mainly constructed of conductive aluminum, which would normally shield and protect the internal systems. However, upon takeoff the shuttle sends out a long exhaust plume as it ascends, and this plume can trigger lightning by providing a current path to ground. The NASA Anvil Rule for a shuttle launch states an anvil cloud cannot appear within a distance of 10 nautical miles.^[13] The Shuttle Launch Weather Officer will monitor conditions until the final decision to scrub a launch is announced. In addition, the weather conditions must be acceptable at one of the Transatlantic Abort Landing sites (One of several Space Shuttle abort modes) to launch. ^[14] While the shuttle might safely endure a lightning strike, a similar strike caused problems on Apollo 12, so for safety NASA chooses not to launch the shuttle if lightning is possible (NPR8715.5). Merritt Island and Kennedy Space Center (shown in white). ... Not to be confused with lighting. ... Electricity (from New Latin Ä“lectricus, amberlike) is a general term for a variety of phenomena resulting from the presence and flow of electric charge. ... It has been suggested that Ground conductor be merged into this article or section. ... A nautical mile is a unit of distance, or, as physical scientists like to call it, length. ... A Space Shuttle abort is an emergency procedure due to equipment failure on NASAs Space Shuttle, most commonly during ascent. ... Apollo 12 was the sixth manned mission in the Apollo program and the second to land on the Moon. ... For other uses, see NASA (disambiguation). ...

The Shuttle has not been launched if its flight will take it from one year to the next (December to January), a year-end rollover (YERO). Its flight software, designed in the 1970s, was not designed for this, and would require the orbiter's computers be reset through a change of year, which could cause a glitch while in orbit. In 2007, NASA engineers devised a solution to this, allowing Shuttle flights to cross the year-end boundary.^[15]

On the day of a launch, after the final hold in the countdown at T minus 9 minutes, the Shuttle goes through its final preparations for launch, and the countdown is automatically controlled by a special computer program at the Launch Control Center. This is known as the Ground Launch Sequencer (GLS), which stops the count if it senses a critical problem with any of the Shuttle's on-board systems. The GLS hands off the count to the Shuttle's on-board computers at T minus 31 seconds, in a process called auto sequence start.

At T minus 16 seconds, the massive sound suppression system (SPS) begins to drench the Mobile Launcher Platform (MLP) and SRB trenches with 300,000 U.S. gallons (1,100 m³) of water to protect the Orbiter from damage by acoustical energy and rocket exhaust reflected from the flame trench and MLP during liftoff. ^[16] A Crawler-Transporter carries a MLP atop. ... Acoustics is a branch of physics and is the study of sound, mechanical waves in gases, liquids, and solids. ...

At T-minus 10 seconds, hydrogen igniters are activated under each engine bell to quell the stagnant gas inside the cones before ignition. Failure to burn these gases can trip the onboard sensors and create the possibility of an overpressure and explosion of the vehicle during the firing phase. The main engine turbopumps are also commanded to begin charging the combustion chambers with liquid hydrogen and liquid oxygen at this time. The computers reciprocate this action by allowing the redundant computer systems to begin the firing phase.

The three Space Shuttle Main Engines (SSMEs) start at T minus 6.6 seconds. The main engines ignite sequentially via the shuttle's general purpose computers (GPCs) at 120 millisecond intervals. The GPCs require that the engines reach 90% of their rated performance to complete the final gimbal of the main engine nozzles to liftoff configuration.^[17] When the SSMEs start, the water from the sound suppression system flashes into a large volume of steam that shoots southward. All three SSMEs must reach the required 100% thrust within three seconds, otherwise the onboard computers will initiate an RSLS abort. If the onboard computers verify normal thrust buildup, at T minus 0 seconds, the SRBs are ignited. At this point the vehicle is committed to takeoff, as the SRBs cannot be turned off once ignited. After the SRBs reach a stable thrust ratio, pyrotechnic nuts are detonated by radio controlled signals from the shuttle's GPC's to release the vehicle ^[18]. The plume from the solid rockets exits the flame trench in a northward direction at near the speed of sound, often causing a rippling of shockwaves along the actual flame and smoke contrails. At ignition, the GPC's mandate the firing sequences via the Master Events Controller, a computer program integrated with the shuttle's four redundant computer systems. There are extensive emergency procedures (abort modes) to handle various failure scenarios during ascent. Many of these concern SSME failures, since that is the most complex and highly stressed component. After the Challenger disaster, there were extensive upgrades to the abort modes. Space Shuttle Main Engine cluster The Space Shuttle Main Engines (SSMEs) are the three main engines on the Space Shuttle orbiter. ... A Space Shuttle abort is an emergency procedure due to equipment failure on NASAs Space Shuttle, most commonly during ascent. ... The Space Shuttle Solid Rocket Booster (SRB) is the rocket that provides 83% of liftoff thrust for the Space Shuttle. ... A Space Shuttle abort is an emergency procedure due to equipment failure on NASAs Space Shuttle, most commonly during ascent. ... For further information about Challengers mission and crew, see STS-51-L. The iconic image of Space Shuttle Challengers smoke plume after its breakup 73 seconds after launch. ...

Shuttle launch of Atlantis at sunset in 2001. The sun is behind the camera, and the plume's shadow intersects the moon across the sky.

STS mission profile

SSLV at Mach 2.46 and 66,000 feet (20,000 m). The surface of the vehicle is colored by the pressure coefficient, and the gray contours represent the density of the surrounding air, as calculated using the OVERFLOW codes.

After the main engines start, but while the solid rocket boosters are still clamped to the pad, the offset thrust from the Shuttle's three main engines causes the entire launch stack (boosters, tank and shuttle) to pitch down about 2 m at cockpit level. This motion is called the "nod", or "twang" in NASA jargon. As the boosters flex back into their original shape, the launch stack pitches slowly back upright. This takes approximately six seconds. At the point when it is perfectly vertical, the boosters ignite and the launch commences. Image File history File links Download high-resolution version (1539x2200, 222 KB) Summary Space Shuttle Atlantis launches at sunset. ... Image File history File links Download high-resolution version (1539x2200, 222 KB) Summary Space Shuttle Atlantis launches at sunset. ... Image File history File links Download high-resolution version (1024x648, 105 KB) Summary Space shuttle mission profile description Licensing I, the creator of this work, hereby release it into the public domain. ... Image File history File links Download high-resolution version (1024x648, 105 KB) Summary Space shuttle mission profile description Licensing I, the creator of this work, hereby release it into the public domain. ...

Shortly after clearing the tower the Shuttle begins a roll and pitch program to set its orbital inclination and so that the vehicle is below the external tank and SRBs, with wings level. The vehicle climbs in a progressively flattening arc, accelerating as the weight of the SRBs and main tank decrease. To achieve low orbit requires much more horizontal than vertical acceleration. This is not visually obvious, since the vehicle rises vertically and is out of sight for most of the horizontal acceleration. The near circular orbital velocity at the 380 km (236 statute miles) altitude of the International Space Station is 7.68 kilometers per second (27,650 km/h, 17,180 mph), roughly equivalent to Mach 23 at sea level. As the International Space Station orbits at an inclination of 51.6 degrees, the Shuttle has to set its inclination to the same value to rendezvous with the station. “Miles” redirects here. ... ISS redirects here. ... Miles per hour is a unit of speed, expressing the number of international miles covered per hour. ...

Around a point called Max Q, where the aerodynamic forces are at their maximum, the main engines are temporarily throttled back to avoid overspeeding and hence overstressing the Shuttle, particularly in vulnerable areas such as the wings. At this point, a phenomenon known as the Prandtl-Glauert singularity occurs, where condensation clouds form during the vehicle's transition to supersonic speed. A visible shock wave formed as the Apollo 11 Saturn V encountered Maximum Dynamic Pressure (Max Q) at about 1 minute 20 seconds into the flight (altitude 12. ... An aircraft can fly too fast but this is not usually termed overspeed which is a term more usually used in relation to engines. ... F/A-18 demonstrating singularity effect The Prandtl-Glauert singularity, at which point a sudden drop in air pressure occurs, is generally accepted as the cause of the visible condensation cloud that often surrounds an airplane traveling at transonic speeds, though there remains some debate. ...

126 seconds after launch, explosive bolts release the SRBs and small separation rockets push them laterally away from the vehicle. The SRBs parachute back to the ocean to be reused. The Shuttle then begins accelerating to orbit on the Space Shuttle main engines. The vehicle at that point in the flight has a thrust-to-weight ratio of less than one — the main engines actually have insufficient thrust to exceed the force of gravity, and the vertical speed given to it by the SRBs temporarily decreases. However, as the burn continues, the weight of the propellant decreases and the thrust-to-weight ratio exceeds 1 again and the ever-lighter vehicle then continues to accelerate toward orbit. An explosive bolt is a fastener that incorporates a pyrotechnic charge that can be initiated by an electrical command. ... Space Shuttle Main Engine cluster The Space Shuttle Main Engines (SSMEs) are the three main engines on the Space Shuttle orbiter. ...

The vehicle continues to climb and takes on a somewhat nose-up angle to the horizon — it uses the main engines to gain and then maintain altitude while it accelerates horizontally towards orbit. At about five and three-quarter minutes into ascent, the orbiter rolls heads up to switch communication links from ground stations to Tracking and Data Relay Satellites. The Tracking and Data Relay Satellite System (TDRSS) is a network of communications satellites (each called a Tracking and Data Relay Satellite or TDRS) used by NASA and other United States government agencies. ...

Finally, in the last tens of seconds of the main engine burn, the mass of the vehicle is low enough that the engines must be throttled back to limit vehicle acceleration to 3g (30 m/s²), largely for astronaut comfort.

Before complete depletion of propellant, as running dry would destroy the engines, the main engines are shut down. The oxygen supply is terminated before the hydrogen supply, as the SSMEs react unfavorably to other shutdown modes. Liquid oxygen has a tendency to react violently, and supports combustion when it encounters hot engine metal. The external tank is released by firing explosive bolts and falls, largely burning up in the atmosphere, though some fragments fall into the Indian Ocean. The sealing action of the tank plumbing and lack of pressure relief systems on the external tank helps it break up in the lower atmosphere. After the foam burns away during reentry, the heat causes a pressure buildup in the remaining liquid oxygen and hydrogen until the tank explodes. This ensures that any pieces that fall back to Earth are small.

To prevent the shuttle from following the external tank back into the lower atmosphere, the Orbital maneuvering system (OMS) engines are fired to raise the perigee higher into the upper atmosphere. On some missions (e.g., missions to the ISS), the OMS engines are also used while the main engines are still firing. The reason for putting the orbiter on a path that brings it back to Earth is not just for external tank disposal. It is one of safety; if the OMS malfunctions, or the cargo bay doors cannot open for some reason, the shuttle is already on a path to return to earth for an emergency abort landing. An OMS pod detached from a Shuttle for maintenance. ...

Since it flies in the upper atmosphere, the craft's orbit slowly decays due to air friction. The orbiter must periodically boost its velocity with the OMS to prevent re-entry into the lower atmosphere.

Re-entry and landing

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Simulation of the outside of the Shuttle as it heats up to over 1,500°C during re-entry.

Almost the entire space shuttle re-entry, except for lowering the landing gear and deploying the air data probes, is normally performed under computer control. However, the re-entry can be flown entirely manually if an emergency arises. The approach and landing phase can be controlled by the autopilot, but is usually hand flown. Image File history File links Stsheat. ... Image File history File links Stsheat. ... “Reentry” redirects here. ...

The vehicle begins re-entry by firing the Orbital maneuvering system engines, while flying upside down, backside first, in the opposite direction to orbital motion for approximately three minutes, giving roughly 200 mph (90 m/s) of delta-v. The resultant slowing of the Shuttle lowers its orbital perigee down into the upper atmosphere. The shuttle then flips over, by pulling its nose up (which is actually "down" because it's flying upside down). This OMS firing is done roughly halfway around the globe from the landing site. Perigee is the point at which an object in orbit around the Earth makes its closest approach to the Earth. ...

The vehicle starts encountering more significant air de