STS-120 was a
Space Shuttle
The Space Shuttle is a retired, partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program ...
mission to the
International Space Station
The International Space Station (ISS) is the largest modular space station currently in low Earth orbit. It is a multinational collaborative project involving five participating space agencies: NASA (United States), Roscosmos (Russia), JAXA ( ...
(ISS) that launched on 23 October 2007 from the
Kennedy Space Center
The John F. Kennedy Space Center (KSC, originally known as the NASA Launch Operations Center), located on Merritt Island, Florida, is one of the National Aeronautics and Space Administration's (NASA) ten field centers. Since December 1968 ...
, 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 , and was the twenty-third Space Shuttle mission to the ISS.
Crew
Crew notes
![Exp16STS120commanders](https://upload.wikimedia.org/wikipedia/commons/4/4c/Exp16STS120commanders.jpg)
As commander of STS-120, Pamela Melroy became the second woman (after
Eileen Collins
Eileen Marie Collins (born 19 November 1956) is a retired NASA astronaut and United States Air Force (USAF) colonel. A former flight instructor and test pilot, Collins was the first woman to pilot the Space Shuttle and the first to command a ...
) to command a Space Shuttle mission.
Additionally, the
Expedition 16
Expedition 16 was the 16th expedition to the International Space Station (ISS).
The first two crew members, Yuri Malenchenko and Peggy Whitson, launched on 10 October 2007, aboard Soyuz TMA-11, and were joined by spaceflight participant Shei ...
crew that received STS-120 was commanded by
Peggy Whitson
Peggy Annette Whitson (born February 9, 1960) is an American biochemistry researcher, retired NASA astronaut, and former NASA Chief Astronaut. Whitson has a total of 665 days in space, more than any other woman or American.
Her first space mi ...
, 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.
Mission payloads
''Harmony'' (Node 2)
![STS120Lightsaber](https://upload.wikimedia.org/wikipedia/commons/8/8c/STS120Lightsaber.jpg)
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
Thales Alenia Space () is a Franco-Italian aerospace manufacturer. A joint venture between the French technology corporation Thales Group (67%) and Italian defense conglomerate Leonardo (33%), the company is the largest satellite manufactur ...
in
Torino
Turin ( , Piedmontese: ; it, Torino ) is a city and an important business and cultural centre in Northern Italy. It is the capital city of Piedmont and of the Metropolitan City of Turin, and was the first Italian capital from 1861 to 1865. T ...
, 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
The Pressurized Mating Adapter (PMA) is a class of spacecraft adapters that convert the Common Berthing Mechanism (CBM) used on the US Orbital Segment to APAS-95 docking ports. There are three PMAs located on the International Space Station (I ...
-2 (PMA-2) on the forward port of the ''
Destiny
Destiny, sometimes referred to as fate (from Latin ''fatum'' "decree, prediction, destiny, fate"), is a predetermined course of events. It may be conceived as a predetermined future, whether in general or of an individual.
Fate
Although often ...
'' 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
European, or Europeans, or Europeneans, may refer to:
In general
* ''European'', an adjective referring to something of, from, or related to Europe
** Ethnic groups in Europe
** Demographics of Europe
** European cuisine, the cuisines of Europe ...
''
Columbus
Columbus is a Latinized version of the Italian surname "''Colombo''". It most commonly refers to:
* Christopher Columbus (1451-1506), the Italian explorer
* Columbus, Ohio, capital of the U.S. state of Ohio
Columbus may also refer to:
Places ...
'' and
Japanese
Japanese may refer to:
* Something from or related to Japan, an island country in East Asia
* Japanese language, spoken mainly in Japan
* Japanese people, the ethnic group that identifies with Japan through ancestry or culture
** Japanese diaspor ...
''
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
The Integrated Truss Structure (ITS) of the International Space Station (ISS) consists of a linear arranged sequence of connected trusses on which various unpressurized components are mounted such as logistics carriers, radiators, solar arrays, ...
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
A lightsaber is a fictional energy sword featured throughout the '' Star Wars'' franchise. A typical lightsaber is depicted as a luminescent plasma blade about in length emitted from a metal hilt around in length. First introduced in the o ...
used by actor
Mark Hamill in the 1983 film ''
Return of the Jedi
''Return of the Jedi'' (also known as ''Star Wars: Episode VI – Return of the Jedi'' is a 1983 American epic space opera film directed by Richard Marquand. The screenplay is by Lawrence Kasdan and George Lucas from a story by Lucas, who ...
'' was flown to the station and returned to Earth.
Stowed on-board ''Discovery'' for the length of the mission, the
prop
A prop, formally known as (theatrical) property, is an object used on stage or screen by actors during a performance or screen production. In practical terms, a prop is considered to be anything movable or portable on a stage or a set, distinc ...
was flown in honor of the 30th anniversary of the ''
Star Wars'' franchise.
On 28 August 2007,
Chewbacca from the ''Star Wars'' films presented the lightsaber to NASA officials from
Space Center Houston
Space Center Houston is a science museum that serves as the official visitor center of NASA Johnson Space Center in Houston. It was designated a Smithsonian Affiliate museum in 2014. The organization is owned by NASA, and operated under a con ...
, in an official ceremony at
Oakland International Airport
Oakland International Airport is an international airport in Oakland, California, United States, 10 miles (16 km) south of downtown located in the San Francisco Bay Area. It is owned by the Port of Oakland and has domestic passenger f ...
.
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 23 October 2007.
NASA originally scheduled the launch for 20 October 2007, but due to the International Space Station program requirement, launch was delayed to 23 October 2007.
In light of the small gouge to the underside of ''Endeavour'' that occurred on
STS-118
STS-118 was a Space Shuttle mission to the International Space Station (ISS) flown by the orbiter '' Endeavour''. STS-118 lifted off on 8 August 2007 from launch pad 39A at Kennedy Space Center (KSC), Florida and landed at the Shuttle Landing Fac ...
, 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
The Integrated Truss Structure (ITS) of the International Space Station (ISS) consists of a linear arranged sequence of connected trusses on which various unpressurized components are mounted such as logistics carriers, radiators, solar arrays ...
(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
Discovery may refer to:
* Discovery (observation), observing or finding something unknown
* Discovery (fiction), a character's learning something unknown
* Discovery (law), a process in courts of law relating to evidence
Discovery, The Discover ...
''
* 95th post-''
Challenger'' mission
* 7th post-''Columbia'' mission
Mission timeline
Launch preparations
![VABmating STS-120](https://upload.wikimedia.org/wikipedia/commons/a/ad/VABmating_STS-120.jpg)
Following STS-118 in August 2007, NASA managers decided to make modifications to the
external tank
The Space Shuttle external tank (ET) was the component of the Space Shuttle launch vehicle that contained the liquid hydrogen fuel and liquid oxygen oxidizer. During lift-off and ascent it supplied the fuel and oxidizer under pressure to ...
to be used on STS-120, and modify the
liquid oxygen
Liquid oxygen—abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries—is the liquid form of molecular oxygen. It was used as the oxidizer in the first liquid-fueled rocket invented in 1926 by Robert H. Goddard, an app ...
feed-line brackets.
The change involved a new low-density foam application, and thinner gaskets. Shuttle Program Managers decided to do this to reduce the foam loss from the area that had been noted since
STS-114's "Return to Flight" mission in 2005. STS-118 had a small gouge on the belly of the orbiter due to a chunk of foam that impacted during launch in August 2007. The week of 17 September 2007, NASA managers decided to delay ''Discovery's'' rollover to the
Vehicle Assembly Building
The Vehicle Assembly Building (originally the Vertical Assembly Building), or VAB, is a large building at NASA's Kennedy Space Center (KSC), designed to assemble large pre-manufactured space vehicle components, such as the massive Saturn V and th ...
(VAB), due to a hydraulic fluid leak from the right main landing gear strut. The strut repair was successfully completed on 19 September 2007. ''Discovery'' then moved to the VAB, and was mated to the External Tank and
Solid Rocket Boosters
A solid rocket booster (SRB) is a large solid propellant motor used to provide thrust in spacecraft launches from initial launch through the first ascent. Many launch vehicles, including the Atlas V, SLS and space shuttle, have used SRBs to giv ...
. Perched atop the
mobile launcher platform
A mobile launcher platform (MLP), also known as mobile launch platform, is a structure used to support a large multistage space vehicle which is assembled (stacked) vertically in an integration facility (e.g. the Vehicle Assembly Building) and t ...
, ''Discovery'' arrived at Launch complex 39A on 30 September 2007.
The crew of STS-120 arrived at Kennedy Space Center on 7 October 2007 and began final preparations, including the
terminal countdown demonstration test, or "Dress Rehearsal", scheduled for 7 October 2007 through 10 October 2007.
On 9 October 2007, NASA's Engineering and Safety Center, an independent review group set up after the 2003 ''Columbia'' disaster, advised replacement of three of ''Discovery's''
reinforced carbon-carbon (RCC) panels on the leading wing edge, due to a loss of small amounts of the protective
silicon
Silicon is a chemical element with the symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic luster, and is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic ta ...
-
carbide
In chemistry, a carbide usually describes a compound composed of carbon and a metal. In metallurgy, carbiding or carburizing is the process for producing carbide coatings on a metal piece.
Interstitial / Metallic carbides
The carbides of th ...
coating.
NASA reviewed the issue of oxidation of the panels for several months, using a variety of specialized testing methods, including
thermography
Infrared thermography (IRT), thermal video and/or thermal imaging, is a process where a thermal camera captures and creates an image of an object by using infrared radiation emitted from the object in a process, which are examples of infrared i ...
.
These tests showed that the panels had not worsened over the course of the past two flights of ''Discovery'', and the orbiter project engineers concluded in August that ''Discovery'' was safe to launch as is.
Had a decision been made to repair the panels, the orbiter would have been rolled back to the VAB, delaying the launch.
On 16 October 2007, NASA Managers completed the Flight Readiness Review, and held a press conference to announce the mission plan.
The issue of the RCC panels raised by NESC was found to be of little immediate concern, because the NESC took pre-flight thermography data from ''Endeavour'' and compared it with ''Discovery'', but there was no commonality in flight history between the two vehicles.
The research showed no significant difference between the panels prior to STS-114, and the panels today, which indicates the coating has not worsened during the previous flights, adding confidence that ''Discovery's'' RCC panels have had no deterioration in the flights since.
NASA announced on the main shuttle page that "The Space Shuttle Program has determined that Discovery's astronauts can safely carry out their mission without having to replace the panels."
23 October (Flight Day 1, Launch)
![STS120LaunchHiRes-edit1](https://upload.wikimedia.org/wikipedia/commons/d/d6/STS120LaunchHiRes-edit1.jpg)
''Discovery'' launched on time at 11:38
EDT (15:38
UTC).
In the countdown's final minutes, a piece of ice, measuring x was seen on the hydrogen umbilical between the orbiter and the external tank. The inspection team was called back to the pad (a contingency that has been practiced, and used before), to get a closer look at the ice build-up. NASA flight controllers deemed it too small to pose a threat to the thermal protection system. The ice was attached to a
Kapton purge barrier near the LH2 umbilical
pyrotechnic
Pyrotechnics is the science and craft of creating such things as fireworks, safety matches, oxygen candles, explosive bolts and other fasteners, parts of automotive airbags, as well as gas-pressure blasting in mining, quarrying, and demolition. ...
canister closeout.
It had been shown in tests that ice on this liner, sometimes called a "baggie", would likely come off at main engine ignition.
Had it been on other metal surfaces around the liner, this may have posed a threat of staying on and breaking off at a critical part of launch. Despite these issues, the launch continued as planned. The forecast for launch initially was a 60% chance of weather prohibiting launch, and although the launch team weather officers were tracking an incoming storm, the weather remained favorable for launch.
Present for the launch was
George Lucas, to see off the Star Wars lightsaber.
In a press briefing following launch, NASA managers noted a few "events" involving debris, but they occurred later in ascent, after the period of maximum aerodynamic
velocity
Velocity is the directional speed of an object in motion as an indication of its rate of change in position as observed from a particular frame of reference and as measured by a particular standard of time (e.g. northbound). Velocity i ...
and speed, and were not concerning.
24 October (Flight day 2)
The crew of STS-120 spent their first full day in space by performing the RCC survey, using the
Shuttle Remote Manipulator System
Canadarm or Canadarm1 (officially Shuttle Remote Manipulator System or SRMS, also SSRMS) is a series of robotic arms that were used on the Space Shuttle orbiters to deploy, manoeuvre, and capture payloads. After the Space Shuttle Columbia disa ...
(SRMS), and the
Orbiter Boom Sensor System
The Orbiter Boom Sensor System (OBSS) was a 50-foot (15.24 m) boom carried on board NASA's Space Shuttles. The boom was grappled by the Canadarm and served as an extension of the arm, doubling its length to a combined total of 100 feet (30 m). At ...
(OBSS).
The crew also worked on various tasks such as inspecting the
Extravehicular Mobility Unit
The Extravehicular Mobility Unit (EMU) is an independent anthropomorphic spacesuit that provides environmental protection, mobility, life support, and communications for astronauts performing extravehicular activity (EVA) in Earth orbit. Introduc ...
s (EMUs, or spacesuits) that will be used on the EVAs, and doing some preliminary work to get ready for docking with the International Space Station on Thursday.
Deputy Shuttle Program Manager and Mission Management Team (MMT) chairman John Shannon noted during the status briefing that the preliminary data the team had reviewed showed no items of concern, and the ascent imagery showed no significant losses prior to SRB separation.
Shannon said there were several items the team was waiting for higher resolution imagery to assess, including a possible protruding gap filler, and some external tank foam losses, but there was nothing to indicate any problems.
Shannon also noted that a vapor trail was seen coming off the external tank for several seconds during launch, but noted that this was a condition seen during both STS-114, and
STS-121
STS-121 was a 2006 NASA Space Shuttle mission to the International Space Station (ISS) flown by . The main purposes of the mission were to test new safety and repair techniques introduced following the ''Columbia'' disaster of February 2003 as w ...
, and was found to be condensate coming off the back side of the tank. Due to the temperature and humidity, combined with the angle of the Sun for ''Discovery's'' launch, the plume appeared more dramatic in some of the imagery. This was considered an "expected condition", and Shannon confirmed it was of no concern.
25 October (Flight day 3)
The crew of STS-120 worked through the rendezvous procedures in the morning leading to the
rendezvous pitch maneuver
The R-bar pitch maneuver (RPM), popularly called the rendezvous pitch maneuver or backflip, was a maneuver performed by the Space Shuttle as it rendezvoused with the International Space Station (ISS) prior to docking. The Shuttle performed a bac ...
which began at 11:34 UTC. Following the RPM, the crew was given the "Go" to dock with the station, and successful docking to the International Space Station occurred at 12:40 UTC.
Following docking, the joint crews conducted a station safety review, and Tani's custom Soyuz seatliner was transferred from ''Discovery'' to the
Soyuz TMA-11
Soyuz TMA-11 was a human spaceflight mission using a Soyuz-TMA spacecraft to transport personnel to and from the International Space Station (ISS). The mission began at 13:22 UTC on October 10, 2007, when the spacecraft was launched from the ...
, with Anderson's seat liner taken into ''Discovery''. This marked the official end of Expedition 16 for Anderson, and the start of Tani's increment.
Just before the two crews signed off to sleep, they were informed that after preliminary review of the RPM photography, focused inspection of the orbiter's heat shield would not be required.
During the MMT briefing, Shannon confirmed that initial evaluation of the available data showed ''Discovery'' to be a "pretty clean vehicle". He also confirmed they were not working any issues or items of interest. Shannon said the piece of ice that was looked at prior to launch dislodged during main engine ignition, and as it fell, the ice appeared to graze the underside of the orbiter at the beginning of ascent, but the area around the impact site was in good condition, and the ice did not appear to have caused any damage.
Shannon said the teams would continue to evaluate the imagery and data, but the shuttle was in a good configuration.
26 October (Flight day 4)
![STS120HarmonyInstalled](https://upload.wikimedia.org/wikipedia/commons/9/92/STS120HarmonyInstalled.jpg)
The two crews started the day by preparing for the mission's first spacewalk, which began at 10:02 UTC, and ended at 16:16 UTC. Parazynski and Wheelock successfully completed all EVA activities, including preparing ''Harmony'' for removal from the payload bay.
Wilson, Tani, and Anderson controlled the station's robotic arm, moving ''Harmony'' out of the bay and onto the port side of the
''Unity'' node. At 15:38 UTC, ''Harmony'' was officially mated to the space station.
The station's new addition adds to the station's living volume, an increase of almost 20%, from to .
At the Mission Management Team meeting, managers cleared ''Discovery's'' heat shield for reentry, and verified that focused inspection was not required, but noted that late inspection will still be performed on flight day 13 following undocking.
John Shannon mentioned that managers have decided to add a task to the second EVA, asking the astronauts to visually inspect the Solar Alpha Rotary Joint (SARJ) on the starboard side, as the joint has registered some vibration for the past month and a half. While the friction is not constant or severe, managers will have Tani remove the insulation covers from the joint to photograph the swing bolts on the joint since Tani would be near the area during the EVA.
27 October (Flight day 5)
![STS120 Day 7 Harmony Model](https://upload.wikimedia.org/wikipedia/commons/2/2c/STS120_Day_7_Harmony_Model.jpg)
The two crews worked to prepare ''Harmony'' for entry in the morning, connecting power and data cables, and at 12:24 UTC, the hatch was opened, and the crew was allowed to enter.
Whitson, Malenchenko, and Nespoli entered first, wearing masks, and installed a temporary air duct to the node, to allow the air inside to circulate through the station's filters.
Until the air is fully exchanged, occupancy of the node is limited to only a few crew members at a time, and they are not to remain inside for extended periods. Some of the work the crew has to do inside the node is to remove approximately 700 screws and bolts that are holding down equipment and panels, placed for security during launch, but not needed in space.
After allowing the ventilation system work for several hours, the two crews participated in a press conference with
CBS
CBS Broadcasting Inc., commonly shortened to CBS, the abbreviation of its former legal name Columbia Broadcasting System, is an American commercial broadcast television and radio network serving as the flagship property of the CBS Entertainm ...
,
Fox News
The Fox News Channel, abbreviated FNC, commonly known as Fox News, and stylized in all caps, is an American multinational conservative cable news television channel based in New York City. It is owned by Fox News Media, which itself is owne ...
, and
WHAM-TV
WHAM-TV (channel 13) is a television station in Rochester, New York, United States, affiliated with ABC and The CW. It is owned by Deerfield Media, which maintains a local marketing agreement (LMA) with Sinclair Broadcast Group, owner of Fox ...
from inside ''Harmony''.
28 October (Flight day 6)
The two crews awoke at 05:08 UTC, and began preparing for the second EVA. Parazynski and Tani began the spacewalk at 09:32 UTC, a half-hour ahead of the planned timeline.
The pair started with the P6 truss, removing the attachments to the Z1 truss, which allowed Wilson and Wheelock to use the station's robotic arm to move the truss to a position where it was "parked" for the night.
Joking to Wilson "Don't drop it!", Parazynski then moved on and installed handrails onto ''Harmony'', while Tani went to inspect some items requested by the managers, including handrails on a Crew and Equipment Translation Aid (CETA) cart, that was considered as a possible cause of
Rick Mastracchio
Richard Alan "Rick" Mastracchio (born February 11, 1960) is an American engineer and former NASA astronaut. He has flown on three NASA Space Shuttle missions as a mission specialist in addition to serving as a Flight Engineer on the Soyuz TMA-1 ...
's glove tear on STS-118.
Tani noted the handrail appeared to be intact, with no obvious sharp edges.
Tani then moved on to the Solar Alpha Rotary Joint (SARJ) that has had an intermittent vibration for over a month. After removing the cover from the joint, Tani called down to the team to let them know he saw some metal shavings, and some wear patterns and discoloration on one of the rings inside the joint.
"It's like the result that you get with the metal, iron filings and you put a magnet under it and they stand straight up."
Tani collected some of the shavings onto some tape, which returned to Earth with the shuttle for further analysis.
Managers decided to add a task to Tuesday's EVA, having Parazynski inspect the port (left side) SARJ, using photography and video to compare it to the starboard SARJ inspected by Tani.
29 October (Flight day 7)
![STS-120 Two Crews](https://upload.wikimedia.org/wikipedia/commons/2/23/STS-120_Two_Crews.jpg)
The two crews used the morning to move the P6 truss from its overnight position on the station's robotic arm, over to the shuttle's robotic arm. The crew then moved the station's arm along the
mobile transporter to an outboard work site that allows attachment of the P6 truss to its new location on the
P5 truss on Tuesday.
Managers on the ground had Whitson perform an experiment on the shavings Tani collected from the SARJ on Sunday's EVA, putting a magnet under a slip of paper, and testing to see if the shavings collected on the paper, to ascertain if they were metal.
The test confirmed the particles collected by Tani were
ferrous
In chemistry, the adjective Ferrous indicates a compound that contains iron(II), meaning iron in its +2 oxidation state, possibly as the divalent cation Fe2+. It is opposed to " ferric" or iron(III), meaning iron in its +3 oxidation state, suc ...
. This information allowed the managers on the ground to rule out some possibilities of the origin of the particles, such as the thermal covers, which are made of aluminized mylar.
The Mission Management Team discussed the SARJ issues with the ISS team, and decided to add an extra docked day to the mission, between flight days 11 and 12.
The new plan changed the objectives of EVA four from the heat shield repair materials testing, to a more thorough inspection of the starboard SARJ. With the new flight plan, ''Discovery'' would undock on 5 November 2007 with a landing on 7 November 2007, at approximately 05:11 EST.
30 October (Flight day 8)
![STS120SolarPanel](https://upload.wikimedia.org/wikipedia/commons/2/25/STS120SolarPanel.jpg)
The two crews spent the morning preparing for the mission's third EVA, which began at 08:45 UTC.
The EVA completed the installation of the P6 solar arrays onto the P5 truss, and the rest of the EVA activities were accomplished successfully, with the EVA ending at 15:53 UTC. Once the P6 solar array was attached, the process of deploying the arrays began. The first set of arrays, 2B, was successfully deployed with no issues, but during the deployment of the 4B array, the crew halted when they noticed an abnormality.
Initial images taken by the crew and station cameras showed what appeared to be a tear in a small portion of the array.
During a press briefing, ISS Program Manager Mike Suffredini said the crew took high resolution images of the solar array, and the managers would analyze the images overnight to determine a course of action.
Sufredini mentioned that with the array in the 90% unfurled position, it was still generating 97% of the expected power to the station, only slightly less than a fully unfurled array.
31 October (Flight day 9)
![STS120President Bush](https://upload.wikimedia.org/wikipedia/commons/f/fa/STS120President_Bush.jpg)
The crew began the day working through a variety of tasks, including preparing for the fourth EVA, installing a Zero Gravity Stowage Rack in ''Harmony'', and working with some of the experiments on board.
Nespoli and Melroy participated in a Public Affairs event (PAO), and received a call from the President of Italy,
Giorgio Napolitano. The entire crew took part in a second PAO event, fielding calls from news agencies from the United States, Europe, and Russia.
Around 15:00 UTC, mission control informed the crew that Thursday's planned EVA would be postponed to either Friday, or perhaps Saturday, to allow for a new EVA plan to be worked out, which would include troubleshooting of the P6 solar arrays.
1 November (Flight day 10)
![STS120 Cufflink](https://upload.wikimedia.org/wikipedia/commons/a/a1/STS120_Cufflink.jpg)
Shortly after awakening in the morning, the crew was informed that the managers had chosen to take an extra day to evaluate and plan the fourth EVA.
Managers initially planned for the EVA to be done on flight day 11, but would use an extra day to conduct further analysis and allow the crew to have extra time to make the tools and equipment needed, and to review and practice the procedures.
The crew took some time out to gather in the ''Harmony'' module to speak with former President
George H. W. Bush and his wife, Barbara, who were visiting Johnson Space Center.
The rest of the day was devoted to assembling and configuring the new equipment and tools that would be required for the solar array repair, including a tool termed a "cufflink". The tear in the array is located at one of the hinges, which carries the load of the array, so the cufflink will be a load-bearing strap to relieve the pressure from the snagged area, transferring the load from the hinge, to the cufflink.
The cufflink is made up of two wires, with two tabs at the end, that are threaded through existing reinforced aluminum holes in the solar array panels.
The EVA plans call for the space station's robotic arm to grapple the shuttle's orbital inspection boom, with an extension on the end, to allow Parazynski to reach the solar array while positioned on a foot restraint at the end of the system.
Wheelock will be watching to let the team know the clearances, and to assist Parazynski and the robotics team with positioning.
With the changes to the timeline, the crew would be shifting their sleep schedule, to allow for a daylight landing on Wednesday, rather than the early morning landing that was originally planned. The fifth EVA that was planned for the Expedition 16 crew during the mission was delayed, and will be performed by the station crew after the shuttle departs.
2 November (Flight day 11)
The shuttle and station crews spent the day discussing the new EVA plan with managers on the ground, reviewing the procedures, completing the tool configurations, and going over the timeline for the fourth EVA, scheduled for Saturday.
The crew also positioned the station's mobile transporter and robotic arm on the end of the truss, to allow the apparatus to reach the solar array. Saturday's EVA would be the first operational use of the Orbiter Boom Sensor System (OBSS) to reach a worksite, although the task was tested and demonstrated during STS-121 to show the boom could provide a stable work platform for EVA activities.
3 November (Flight day 12)
![STS120EVA4](https://upload.wikimedia.org/wikipedia/commons/0/08/STS120EVA4.jpg)
After being awakened by the theme music from ''
Star Wars'', the station and shuttle crews got to work preparing for the mission's fourth EVA.
The spacewalk began at 10:03 UTC. After translating out to the robotic arm, Parazynski attached himself to the adjustable portable foot restraint (APFR), and was taken to the solar array worksite.
Working slowly, with direction from Wheelock and the ground team, Parazynski secured the five cufflinks to the array, and then backed away to observe the deploy action.
Inside the station, the crew deployed the array a half a "bay" at a time, and the array was fully deployed at 15:23 UTC.
After performing additional inspections of both the 2B, and 4B arrays, Parazynski and Wheelock finished the EVA at 17:22 UTC.
With the mission's final spacewalk completed, Parazynski has completed seven EVAs, for a total time of 47 hours, 05 minutes, placing him 5th overall for total EVA duration.
Wheelock completed three EVAs, for a total time of 20 hours, 41 minutes, and the total EVA time for STS-120 was 27 hours, 14 minutes.
During the EVA, a pair of
needlenose pliers floated free of the equipment, and was observed floating nearby the window by the crew inside the station. The tool floated clear of the station, and was not a hazard.
4 November (Flight day 13)
![ISS after STS-120 in November 2007](https://upload.wikimedia.org/wikipedia/commons/d/d1/ISS_after_STS-120_in_November_2007.jpg)
The Shuttle and station crews spent the day transferring cargo, and resting in preparation for Monday's departure of ''Discovery''. Nespoli and Melroy spent some time in the morning speaking to the Italian media, and later in the day the crew had some off-duty time. Following the traditional farewell ceremony, the hatches were closed at 20:03 UTC.
During the emotional ceremony, Anderson spoke to the ground crew, expressing his gratitude for their support during his 137 days as an Expedition crewmember.
5 November (Flight day 14)
The two crews spent the morning preparing for ''Discovery's'' undocking from the International Space Station.
At 10:32 UTC, the orbiter successfully backed away from the Pressurized Mating Adapter on the ''Destiny'' Laboratory, and pilot Zamka began the fly-around to allow the shuttle crew to photograph the new configuration of the station.
After performing the final separation burn, focused inspection began, to scan the wing leading edges and nose cap, the final analysis that allows the ground team to clear the orbiter for re-entry on Wednesday.
6 November (Flight day 15)
The crew of ''Discovery'' spent the day preparing Wednesday's landing.
In addition to doing final packing and stowing activities, Melroy and Zamka did a check of the orbiter's systems, including the flight control systems, and the reaction control system jets.
The crew took some time out in the morning to speak to the media, and then had a deorbit preparation briefing with the ground team. Melroy performed a burn of the orbiter's engines in the afternoon, an orbit adjustment burn done to refine the orbiter's trajectory for the two Wednesday landing opportunities at Kennedy Space Center. NASA managers officially cleared ''Discoverys heat shield for landing after reviewing the data sent down by the final inspection on Monday.
7 November (Flight day 16, Landing)
![STS120LandingKSC](https://upload.wikimedia.org/wikipedia/commons/e/e8/STS120LandingKSC.jpg)
The crew of ''Discovery'' got to work preparing for landing following their wake up call. NASA did not activate either
Edwards Air Force Base, or
White Sands, as the weather looked favorable for both
landing
Landing is the last part of a flight, where a flying animal, aircraft, or spacecraft returns to the ground. When the flying object returns to water, the process is called alighting, although it is commonly called "landing", "touchdown" or ...
opportunities at Kennedy. The weather forecast at the
Shuttle Landing Facility
The Shuttle Landing Facility (SLF) also known as Launch and Landing Facility (LLF) is an airport located on Merritt Island in Brevard County, Florida, United States. It is a part of the Kennedy Space Center and was used by Space Shuttle for ...
called for good visibility, with mostly sunny skies, although the headwinds would be evaluated, as they had been peaking at . Due to the sleep shifting done by the crew earlier in the mission to schedule the extra mission days, the landing was done on what is called a "descending" node entry. Unlike ascending node entries, this entry trajectory brought the shuttle diagonally across the United States for the first time since
STS-107
STS-107 was the 113th flight of the Space Shuttle program, and the 28th and final flight of Space Shuttle ''Columbia''. The mission launched from Kennedy Space Center in Florida on January 16, 2003, and during its 15 days, 22 hours, 20 minutes ...
. The shuttle passed over Vancouver,
British Columbia
British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...
, Canada, and angled down towards Florida.
Once the orbiter reached Florida, Melroy performed a 195-degree right overhead turn along the heading alignment cone (HAC) in order to line up for a landing on Runway 33.
The first landing opportunity began with a deorbit burn at 16:59 UTC and finished with a landing at 13:01 EST.
The deorbit burns were done to slow the orbiter's speed and to drop it out of freefall orbit and on target for the designated runway.
''Discovery's'' payload bay doors were closed at 14:13 UTC, and the crew began fluid loading at 16:00 UTC. Fluid loading is a procedure that involves drinking high salt content fluids, which allows the astronauts to adjust to the return to gravity, and reduces the chance of
hypotension
Hypotension is low blood pressure. Blood pressure is the force of blood pushing against the walls of the arteries as the heart pumps out blood. Blood pressure is indicated by two numbers, the systolic blood pressure (the top number) and the dia ...
upon returning to Earth.
Shortly after 16:00 UTC, the crew began to get into their launch and entry suits, and ingress into their respective seats for landing.
At 16:50 UTC, Entry Flight Director
Bryan Lunney
Bryan Lunney (born January 12, 1966) is an American aerospace engineer and former NASA flight director.
Early life
The son of Apollo-era flight director Glynn Lunney (1936–2021), Bryan Lunney grew up in Friendswood, Texas, and attended Friends ...
gave the crew the "go" for deorbit burn. The initiation of the burn committed ''Discovery'' to landing. The burn was initiated at 16:59 UTC, and was one minute and 53 seconds in duration.
The deorbit burn is performed while the orbiter is facing opposite its direction of travel, which allows the engines to act as a braking system, slowing its speed by approximately . After the burn, the remaining propellant in the orbiter's maneuvering thrusters was dumped overboard, at 17:13 UTC.
''Discovery'' began to feel the effects of gravity around , as it traveled above the North Pacific Ocean at 17:30 UTC.
As the orbiter descended, Melroy initiated a series of "rolls", and roll reversals, which serve to create friction and bleed off additional speed. At 17:40 UTC, ''Discovery'' entered the United States, flying over
Montana
Montana () is a state in the Mountain West division of the Western United States. It is bordered by Idaho to the west, North Dakota and South Dakota to the east, Wyoming to the south, and the Canadian provinces of Alberta, British Columb ...
. At 17:53, the orbiter entered Florida, flying at a speed of , and an altitude of .
''Discovery'' touched down on runway 33 at 13:01:18 EST, the rear landing gear touching down first, the nose gear touching down at 13:01:32 EDT, and the orbiter came to a complete stop at 13:02:13 EDT.
Total mission time was 15 days, 2 hours, 23 minutes, 55 seconds, for a distance of 6.25 million miles in 238 orbits.
The completion of STS-120 marks the longest duration mission for ''Discovery''.
Extra-vehicular activity
Four spacewalks were scheduled and completed during STS-120.
The cumulative time in extra-vehicular activity during the mission was 27 hours and 14 minutes.
ESA ''Esperia'' mission
In addition to his participation in the ISS assembly mission during the STS-120 flight, Paolo Nespoli conducted science research as part of th
Esperia missionfor ESA.
According to the STS-120 press kit, Nespoli was to carry out a number of experiments on behalf of the European science community.
Two of these experiments (Chromosome‐2 and Neocytolysis) were sponsored by ESA. The other three (HPA, FRTL‐5 and SPORE) were sponsored by the
Italian Space Agency
The Italian Space Agency ( it, Agenzia Spaziale Italiana; ASI) is a government agency established in 1988 to fund, regulate and coordinate space exploration activities in Italy. The agency cooperates with numerous national and international enti ...
. Chromosome‐2, Neocytolysis and HPA were experiments in the field of human physiology. FRTL‐5 and SPORE were biology experiments.
Wake-up calls
NASA began a tradition of playing music to astronauts during the
Gemini program, which was first used to wake up a flight crew during
Apollo 15.
Each track is specially chosen, often by their families, and usually has a special meaning to an individual member of the crew, or is applicable to their daily activities.
Contingency mission
STS-320 was the designation given to the
Contingency Shuttle Crew Support mission which would have been launched in the event Space Shuttle ''Discovery'' became disabled during STS-120.
It would have been a modified version of the
STS-122
STS-122 was a NASA Space Shuttle mission to the International Space Station (ISS), flown by the . STS-122 marked the 24th shuttle mission to the ISS, and the 121st Space Shuttle flight overall.
The mission was also referred to as ISS-1E by the ...
mission, which would have involved the launch date being brought forward. If it had been needed, it would have been launched no later than 5 January 2008. The crew for this mission would have been a four-person subset of the full STS-122 crew.
Media
See also
*
2007 in spaceflight
The year 2007 contained several significant events in spaceflight, including a Chinese ASAT test, the launches of the US Phoenix and Dawn missions to study Mars and Asteroid belt respectively, Japan's Kaguya Lunar orbiter, and the first Chi ...
*
List of human spaceflights
This is a list of all human spaceflights throughout history. Beginning in 1961 with the flight of Yuri Gagarin aboard Vostok 1, human spaceflight occurs when a human crew flies a spacecraft into outer space. Human spaceflight is distinguished ...
*
List of International Space Station spacewalks
On the International Space Station (ISS), extravehicular activities are major events in the building and maintaining of the orbital laboratory, and are performed to install new components, re-wire systems, modules, and equipment, and to mon ...
*
List of Space Shuttle missions
*
Lists of spacewalks and moonwalks
Lists of spacewalks and moonwalks include:
By date:
* List of spacewalks and moonwalks 1965–1999
* List of spacewalks 2000–2014
* List of spacewalks since 2015
By space station:
* List of Salyut spacewalks
* List of Mir spacewalks
* List of ...
References
External links
Official STS-120 Mission PageNASA's STS-120 multimedia pagean
STS-120 Fact Sheet – NASA
{{Use American English, date=January 2014
Space Shuttle missions
Spacecraft launched in 2007
Spacecraft which reentered in 2007
Articles containing video clips