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Aura at 20 Years

Introduction

In the 1990s and early 2000s, an international team of engineers and scientists designed an integrated observatory for atmospheric composition – a bold endeavor to provide unprecedented detail that was essential to understanding how Earth’s ozone (O3) layer and air quality respond to changes in atmospheric composition caused by human activities and natural phenomena. This work addressed a key NASA Earth science objective. Originally referred to as Earth Observing System (EOS)–CHEM (later renamed Aura,) the mission would become the third EOS Flagship mission, joining EOS-AM 1 (Terra) launched in 1999 and EOS-PM 1 (Aqua), launched in 2002. The Aura spacecraft – see Figure 1 – is similar in design to Terra and identical to Aqua. Aura and its four instruments were launched on July 15, 2004 from Vandenberg Air Force Base (now Space Force Base) in California – see Photo.

Aura 20 figure 1
Figure 1. An artist’s representation of the Aura satellite in orbit around the Earth.
Image credit: NASA
Aura nighttime launch photo
Photo.  A photo of the nighttime launch of Aura on July 15, 2004.
Image credit: NASA

In 2014 The Earth Observer published an article called  “Aura Celebrates Ten Years in Orbit,” [Nov–Dec 2014, 26:6, pp. 4–18] which details the history of Aura and the first decade of science resulting from its data. Therefore, the current article will focus on the science and applications enabled by Aura data in the last decade. It also examines Aura’s future and the legacies of the spacecraft’s instruments. Readers interested in more information on Aura and the scientific research and applications enabled by its data can visit the Aura website.

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Recent Science Achievements from Aura’s Instrument (in alphabetical order)

High Resolution Dynamics Limb Sounder

The capabilities of the High Resolution Dynamics Limb Sounder (HIRDLS) were compromised at launch and operations ceased in March 2008 due to an image chopper stall. Nevertheless, the HIRDLS team was able to produce a three-year dataset notable for high vertical resolution profiles of greater than 1 km (0.62 mi) for temperature and O3 in the upper troposphere to the mesosphere. Though limited, the HIRDLS dataset demonstrated the incredible potential of the instrument for atmospheric research. So much so, that scientists are now in the study phase for a new instrument, part of the proposed Stratosphere Troposphere Response using Infrared Vertically-Resolved Light Explorer (STRIVE) mission, which would have similar capabilities as HIRDLS with advancements in spectral and spatial imaging. (STRIVE is one of four missions currently undergoing one-year concept studies, as part of NASA’s Earth System Explorer Program, which was established in the 2017 Earth Science Decadal Survey. Two winning proposals will be chosen in 2025 for full development and launch in 2030 or 2032.)

Microwave Limb Sounder

The Microwave Limb Sounder (MLS) was developed to study: 1) the evolution and recovery of the stratospheric O3 layer; 2) the role of the stratosphere, notably stratospheric humidity, in climate feedback processes; and 3) the behavior of air pollutants in the upper troposphere. MLS measures vertical profiles from the upper troposphere at ~10 km altitude (6.2 mi) to the mesosphere at ~90 km (56 mi) of 16 trace gases, temperature, geopotential height, and cloud ice. Its unique measurement suite has made it the “go-to” instrument for most data-driven studies of middle atmosphere composition over the last two decades.

Data collection during the past decade has highlighted the ability of the stratosphere to exhibit surprising and/or envelope-redefining behavior, (Envelope-redefining is a term that is used to refer to an event that greatly exceeded previous observed ranges of this event.) MLS observations have been crucial for the discovery and diagnoses of these extreme events. For example, in 2019, a stratospheric sudden warming over the southern polar cap in September – rare in the Antarctic – curtailed chemical processing, leading to an anomalously weak O3 hole. As another example, prolonged hot and dry conditions in Australia during the subsequent 2019–2020 southern summer promoted the catastrophic “Australian New Year” (ANY) fires. MLS observations showed that fire-driven pyrocumulonimbus convection lofted plumes of polluted air into the stratosphere to a degree never seen during the Aura mission.

Apart from those individual plumes, smoke pervaded the southern lower stratosphere, leading to unprecedented perturbations in southern midlatitude lower stratospheric composition, with chlorine (Cl) shifting from its main reservoir species, hydrochloric acid (HCl), into the O3-destroying form, hypochlorite (ClO). Peak anomalies in chlorine species occurred in mid-2020 – months after the fires. State-of-the-art atmospheric chemistry models in which wildfire smoke has properties similar to those of sulfate (SO4) aerosols were unable to reproduce the observed chemical redistribution. New model simulations assuming that HCl dissolves more readily in smoke than in SO4 particles under typical midlatitude stratospheric conditions better match the MLS observations.

As extraordinary as these events were, their impacts on the stratosphere were spectacularly eclipsed by the impact of the January 2022 eruption of the Hunga Tonga-Hunga Ha’apai  (Hunga) volcano in the Pacific Ocean. The Hunga eruption lofted about 150 Tg of water vapor into the stratosphere – with initial injections reaching into the mesosphere. The eruption almost instantaneously increased total stratospheric water vapor by about 10%. MLS was the only sensor able to track the plume in the first weeks following the eruption. The Hunga humidity enhancement resulted in an envelope-redefining, low-temperature anomaly in the stratosphere, in turn inducing changes in stratospheric circulation. Repartitioning of southern midlatitude Cl also occurred, though to a lesser degree than following the ANY fires and in a manner broadly consistent with known chemical mechanisms. The Hunga water vapor enhancement has not substantially declined in the 2.5 years since the eruption, and studies indicate that it will likely endure for several more years.

Impacts of the Hunga humidity on polar O3 loss have also been investigated. The timing and location of the eruption were such that the plume reached high southern latitudes only after the 2022 Antarctic winter vortex had developed. Since the strong winds at the vortex edge present a transport barrier, polar stratospheric cloud (PSC) formation and O3 hole evolution were largely unaffected. When the vortex broke down at the end of the 2022 Antarctic winter, moist air flooded the southern polar region, increasing humidity in the region. Cold, moist conditions led to unusually early and vertically extensive PSC formation and Cl activation, but chemical processing ran to completion by mid-July, as typically occurs in southern winter. The cumulative chemical O3 losses ended up being unremarkable throughout the lower stratosphere. The Hunga plume was also largely excluded from the 2022–2023 Arctic vortex. The 2023–2024 Arctic O3 loss season was characterized by conditions that were dynamically disturbed and not persistently cold, and springtime O3 was near or above average. The extraordinary stratospheric hydration from Hunga has so far had minimal impact on chemical processing and O3 loss in the polar vortices in either hemisphere – see Figure 2.

Aura 20 figure 2
Figure 2. The evolution of MLS water vapor anomalies (deviations from the baseline 2005–2021 climatology) from January 2019 through December 2023 as a function of equivalent latitude at 700 K potential temperature in the middle stratosphere at ~27 km altitude (17 mi). Black contours mark the approximate edge of the polar vortex. The green triangle marks the time of the main Hunga eruption at latitude 20.54°S on January 15, 2022.
Figure credit: Updated and adapted from a 2023 paper in Geophysical Research Letters

With the end of Aura and MLS, the future for stratospheric limb sounding observations is unclear. While stratospheric O3 and aerosol will continue to be measured on a daily, near-global basis by the Ozone Mapping and Profiler Suite (OMPS) Limb Profiler (OMPS-LP) instruments on the Suomi National Polar-orbiting Partnership (Suomi NPP) and Joint Polar Satellite System (JPSS-2, -3, and -4) satellites, there are no confirmed plans for daily, near-global observations of either long-lived trace gases or halogenated species – both of which are needed to diagnose observed changes in O3. The only other sensor making such measurements, the Canadian Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE–FTS), is itself older than MLS and, as a solar occultation instrument, measures only 30 profiles-per-day, taking around a month to cover all latitudes. Similarly, no other sensor is set to provide daily, near-global measurements of stratospheric water vapor until the launch of the Canadian High-altitude Aerosols, Water vapour and Clouds (HAWC) mission in the early 2030s. Some potential new mission concepts are under consideration by both NASA and ESA, but they are subject to competition. Even if both instruments are ultimately selected, gaps in the records of many species measured by MLS are inevitable. The MLS PI is leading an effort to develop new technologies that would allow an instrument that could restart MLS measurements to be built in a far smaller mass/power footprint (e.g., 60 kg, 90 W vs. 500 kg, 500 W for Aura MLS), and technologies exist for yet-smaller MLS-like instruments that could assume the legacy of the highly impactful MLS record at low cost in future decades.

Ozone Monitoring Instrument

The Ozone Monitoring Instrument (OMI) continues the Total Ozone Mapping Spectrometer (TOMS) record for total O3 and other atmospheric parameters related to O3 chemistry and climate. It employs hyperspectral imaging in a push-broom mode to observe solar backscatter radiation in the visible and ultraviolet.

OMI is a Dutch–Finnish contribution to the Aura mission, and its remarkable stability and revolutionary two-dimensional (2D) detector (spatial in one dimension and spectral in the other) has produced a two-decade record of science- and trend-quality datasets of atmospheric column observations. OMI continues the long-term record of total column O3 measurements begun in 1979, and its observations of nitrogen dioxide (NO2), sulfur dioxide (SO2), formaldehyde (CH2O), and absorbing aerosols provided exceptional spatial resolution for study of anthropogenic and natural trends and variations of these pollutants around the world. Its radiometric and spectral stability has made it a valuable contributor for solar spectral irradiance measurements to complement dedicated solar instruments on other satellites. The many achievements made possible with OMI are documented in a review article.

OMI’s multidecade data records have revolutionized the ability to monitor air quality changes around the world, even at the sub-urban level. In particular, OMI NO2 data have been transformative. Recently, these data were used to track changes in air pollution associated with efforts to control the spread of SARS-CoV-2. OMI’s long, stable data record allowed for changes in pollution levels in 2020 – at the height of global lockdowns – to be put into historical perspective, especially within the envelope of typical year-to-year variations associated with meteorological variability. Many research studies assessed the impact of the pandemic lockdowns on air pollution, supporting novel uses of OMI data for socioeconomic-related research. For example, OMI NO2 data were shown to serve as an environmental indicator to evaluate the effectiveness of lockdown measures and as a significant predictor for the deceleration of COVID-19 spread. OMI NO2 data were also used as a proxy for the economic impact of the pandemic as NO2 is emitted during fossil fuel combustion, which is another proxy for economic activity since most global economies are driven by fossil fuels – see Animation.

Animation. OMI data show changes in average levels of NO2 from March 20 to May 20 for each year from 2015 to 2023 over the northeast U.S. Levels in 2020 were ~30%  lower relative to previous years because of efforts to slow the spread of COVID-19. OMI data indicate similar reductions in NO2 in cities across the globe in early 2020 and a gradual recovery in pollutant emissions in late 2020 into 2023. Additional images for other world cities and regions are available through the NASA Science Visualization Studio website and the Air Quality Observations from Space website.

OMI’s datasets are being continued by successor 2D detector array instruments, such as the previously mentioned Copernicus Sentinel-5P TROPOMI mission, the Republic of Korea’s Geostationary Environment Monitoring Spectrometer (GEMS), and NASA’s Tropospheric Emissions: Monitoring of Pollution (TEMPO). All of these missions have enhanced spatial resolution relative to OMI, but have benefited from the innovative retrieval algorithms pioneered by OMI’s retrieval teams.

Tropospheric Emission Spectrometer

The Tropospheric Emission Spectrometer (TES) provided vertically-resolved distributions of a number of tropospheric constituents, e.g., O3, methane (CH4), and various volatile organic compounds. The instrument was decommissioned in 2018 due to signs of aging associated with a failing Interferometer Control System motor encoder bearing. Nevertheless, TES measurements led to a number of key results regarding changes in atmospheric composition that were published over the past 10 years.

Measurements from TES, OMI, and MLS showed that transport of O3 and its precursors from East Asia offset about 43% of the decline expected in O3 over the western U.S., based on emission reductions observed there over the period 2005–2010. TES megacity measurements revealed that the frequency of high-O3 days is particularly pronounced in South Asian megacities, which typically lack ground-based pollution monitoring networks. TES water vapor and semi-heavy water measurements indicated that water transpired from Amazonian vegetation becomes a significant moisture source for the atmosphere, during the transition from dry to wet season. The increasing water vapor provides the fuel needed to start the next rainy season. Measurements of CH4 from TES and carbon monoxide (CO) from Measurements of Pollution in the Troposphere (MOPITT) on Terra showed that CH4 emissions from fires declined at twice the rate expected from changes in burned area from 2004–2014. This finding helped to balance the CH4 budget for this period, because it offset some of the large increases in fossil fuel and wetland emissions. Through direct measurement of the O3 greenhouse gas effect, TES instantaneous radiative kernels revealed the impact of hydrological controls on the O3 radiative forcing and were used to show substantial radiative bias in Intergovernmental Panel on Climate Change (IPCC) chemistry–climate models. The TES team pioneered the retrieval of a number of species, such as peroxyacetyl nitrate, carbonyl sulfide, and ethylene.

The spirit of TES lives on through the NASA TRopospheric Ozone and its Precursors from Earth System Sounding (TROPESS) project, which generates data products of O3 and other atmospheric constituents by processing data from multiple satellites through a common retrieval algorithm and ground data system. TROPESS builds upon the success of TES and is considered a bridge to allow the development of a continuous record of O3 and other trace gas species as a follow-on to TES.

Future of Aura

In April 2023, Aura’s mission operations team performed the last series of maneuvers to maintain its position in the A-Train constellation of satellites. Since then, Aura has begun drifting. As of July 2024, Aura has descended ~5 km (3 mi) in altitude from ~700 km (435 mi) and its equator crossing time has increased by ~9 min from ~1:44 PM local time. This amount of drift is small, and the Aura MLS and OMI retrieval teams are ensuring the science- and trend-quality of the datasets.

As Aura continues to drift, the amount of sunlight reaching its solar panels will slowly decrease and will no longer be able to generate sufficient power to operate the spacecraft and instruments by mid-2026. At this point, the amount of local time drift will still be relatively small – less than one hour – so the retrieval teams will be able to ensure quality for most data products until this time.

In the remaining years, Aura’s aging but remarkably stable instruments will continue to add to the unprecedented two decades of science- and trend-quality data of numerous key tropospheric and stratospheric constituents. Aura data will be key for monitoring the evolution of the Hunga volcanic plume and understanding its continued impact on the chemistry and dynamics of the stratosphere. Observations from MLS and OMI will also be used to evaluate data from new and upcoming instruments (e.g., ESA’s Atmospheric Limb Tracker for Investigation of Upcoming Stratosphere (Altius); NASA’s TEMPO, Plankton, Aerosol, Cloud, ocean Ecosystem (PACE), and Total and Spectral Solar Irradiance Sensor-2 (TSIS-2) missions, or at least used to help minimize the gaps between data collections.

Aura’s Scientific Legacy

The Aura mission has been nothing short of transformative for atmospheric research and applied sciences. The multidecade, stable datasets have furthered process-based understanding of the chemistry and dynamics of atmospheric trace gases, especially those critical for understanding the causes of trends and variations in Earth’s protective ozone layer.  

The two decades that Aura has flown have been marked by profound atmospheric changes and numerous serendipitous events, both natural and man-made. The data from Aura’s instruments have given scientists and applied scientists an unparalleled view – including at the sub-urban scale – of air pollution around the world, clearly showing the influence of rapid industrialization, environmental regulations designed to improve air quality, seasonal agricultural burning, catastrophic wildfires, and even a global pandemic, on the air we breathe. The Aura observational record spans the period that includes the decline of O3-destroying substances, and Aura data illustrate the beginnings of the recovery of the Antarctic O3 hole, a result of unparalleled international cooperation to reduce these substances.

Aura’s datasets have given a generation of scientists the most comprehensive global view to date of critical gases in Earth’s atmosphere and the chemical and dynamic processes that shape their concentrations. Many, but not all, of these datasets are being/will be continued by successor instruments that have benefited from the novel technologies incorporated into the design of Aura’s instruments as well as the innovative retrieval algorithms pioneered by Aura’s retrieval teams.

Black Separator Line

Acknowledgements
The author wishes to acknowledge the decades of hard work of the many hundreds of people who have contributed to the success of the international Aura mission. There are too many to acknowledge here and I’m sure that many names from the early days are lost to time. I would like to offer special thanks to those scientists who, back in the 1980s, first dreamed of the mission that would become Aura.

Black Separator Line

Bryan Duncan
NASA’s Goddard Space Flight Center (GSFC)

bryan.n.duncan@nasa.gov

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Sep 16, 2024

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    • By NASA
      On Feb. 11, 2000, space shuttle Endeavour took to the skies on its 14th trip into space on the Shuttle Radar Topography Mission (SRTM). The international STS-99 crew included Commander Kevin Kregel, Pilot Dominic Gorie, and Mission Specialists Gerhard Thiele of Germany representing the European Space Agency, Janet Kavandi, Janice Voss, who served as payload commander on the mission, and Mamoru Mohri of the National Space Development Agency (NASDA) of Japan, now the Japan Aerospace Exploration Agency.  
      During their 11-day mission, the astronauts used the radar instruments in Endeavour’s payload bay to obtain elevation data on a near global scale. The data produced the most complete, high-resolution digital elevation model of the Earth. The SRTM comprised a cooperative effort among NASA with the Jet Propulsion Laboratory (JPL) in Pasadena, California, managing the project, the Department of Defense’s National Imagery and Mapping Agency, the German space agency, and the Italian space agency. Prior to SRTM, scientists had a more detailed topographic map of Venus than of the Earth, thanks to the Magellan radar mapping mission. 

      The STS-99 crew patch. Official photo of the STS-99 crew of Janice Voss, left, Mamoru Mohri of the National Space Development Agency of Japan, now the Japan Aerospace Exploration Agency, Kevin Kregel, Dominic Gorie, Gerhard Thiele of Germany representing the European Space Agency, and Janet Kavandi. The Shuttle Radar Topography Mission patch. Schematic of the Space Radar Topography Mission payloads including the deployed mast. The mast antenna during preflight processing. NASA assigned the STS-99 crew in October 1998. For Kregel, selected by NASA as an astronaut in 1992, STS-99 marked his fourth trip to space, having served as pilot on STS-70 and STS-78 and commanded STS-87. Gorie and Kavandi, both selected in 1994, previously flew together as pilot and mission specialist, respectively, on STS-91, the final Shuttle Mir docking mission. Voss, selected in 1990, served as a mission specialist on STS-57 and STS-63, and as payload commander on STS-83 and STS-94. NASDA selected Mohri as an astronaut in 1985 and he previously flew as a payload specialist on STS-47, the Spacelab-J mission. Selected as an astronaut by the German space agency in 1987, Thiele joined the European Astronaut Corps in 1998, completing his first spaceflight on STS-99.  
      The SRTM used an innovative technique called radar interferometry to image the Earth’s landmasses at resolutions up to 30 times greater than previously achieved. Two of the synthetic aperture radar instruments comprising the SRTM payload had flown previously, on the STS-59 Shuttle Radar Laboratory-1 (SRL-1) and the STS-68 SRL-2 missions in April and October 1994, respectively.  A second receiver antenna, placed at the end of a 200-foot deployable mast, enabled the interferometry during SRTM. 

      The SRTM payload in Endeavour’s cargo bay in the orbiter processing facility. Endeavour rolls out to Launch Pad 39A. The STS-99 crew walks out of crew quarters for the van ride to the launch pad. Workers rolled Endeavour to the Vehicle Assembly Building on Dec. 2 for mating with its external tank and solid rocket boosters, and then out to Launch Pad 39A on Dec. 13. The astronauts traveled to Kennedy to participate in the Terminal Countdown Demonstration Test Jan. 11-14, returning afterwards to Houston for final training. They traveled back to Kennedy on Jan. 27 for the first launch attempt four days later. After two launch attempts, the STS-99 mission prepared to liftoff on Feb. 11, 2000. 
      Liftoff! Space shuttle Endeavour takes to the skies to begin the STS-99 mission. At 12:43 p.m. EST, Endeavour thundered into the sky from Kennedy’s Launch Pad 39A to begin the STS-99 mission. Thirty-seven minutes later, a brief firing of the orbiter’s two engines placed Endeavour in the proper 145-mile orbit for the radar scanning. 

      The SRTM instruments in Endeavour’s payload bay with the mast holding the second antenna receiver deployed at right. The antenna at the end of the deployed mast. STS-99 astronauts Janet Kavandi, left, Dominic Gorie, and Mamoru Mohri in Endeavour’s middeck. Astronaut Janice Voss in the commander’s seat on Endeavour’s flight deck. Astronauts Kevin Kregel, left, and Gerhard Thiele on Endeavour’s flight deck. Shortly after reaching orbit, the crew opened the payload bay doors and deployed the shuttle’s radiators.   Kavandi and Thiele turned on the instruments, deployed the 200-foot mast, and conducted initial checkouts of the radars. The crew split into two shifts to enable data collection around the clock during the mission. After overseeing the initial activation of the radars, the red shift of Kregel, Kavandi, and Thiele began their first sleep period as the blue shift of Gorie, Voss, and Mohri picked up with activation and began the first data takes. 
      The major crew activity for SRTM involved changing tapes every 30 minutes. The SRTM generated 332 high density tapes during more than 222 hours of data collection and these recordings covered 99.96 percent of the planned observations. Data collection finished on the mission’s 10th flight day, after which the astronauts reeled the mast back into its container in the payload bay. 

      EarthKAM image of the greater Boston area. The EarthKAM camera mounted in a space shuttle window. STS-99 crew Earth observation photograph of El Paso, Texas, and Ciudad Juarez, Mexico. STS-99 crew Earth observation photograph of the Galapagos Islands. STS-99 crew Earth observation photograph of the greater New York area. STS-99 crew Earth observation photograph of Erg Chech, or sand sea, in the Algerian Sahara. NASA’s EarthKAM program enabled middle school students to remotely take photographs of the Earth using an electronic still camera mounted in one of the shuttle’s windows. The University of California at San Diego houses the control center for EarthKAM, linked with middle schools via the Internet. Students choose Earth targets of interest, and the camera takes photos of that region as the shuttle passes overhead. A then-record 75 schools from around the world participated in the EarthKAM project on STS-99, the camera returning 2,715 images of the Earth. 
      The STS-99 astronauts also spent time taking photographs of the Earth using handheld cameras and the high inclination orbit enabled views of some parts of the Earth rarely seen by shuttle astronauts. 

      The six-person STS-99 crew pose for their inflight photo. Kevin Kregel guides Endeavour to a smooth touchdown on the Shuttle Landing Facility at NASA’s Kennedy Space Center in Florida. The STS-99 crew poses with NASA Administrator Daniel Goldin under Endeavour at the Shuttle Landing Facility at NASA’s Kennedy Space Center in Florida. Kevin Kregel addresses the crowd at Houston’s Ellington Field during the welcome home ceremony for the STS-99 crew. On Feb. 22, the crew closed Endeavour’s payload bay doors, donned their launch and entry suits, and strapped themselves into their seats for entry and landing. Kregel piloted Endeavour to a smooth landing on Kennedy’s Shuttle Landing Facility. The crew had flown 181 orbits around the Earth in 11 days, 5 hours, and 39 minutes. Enjoy the crew narrate a video about the STS-99 mission.  
      Postscript 

      Final coverage map for the SIR-C radar, indicating 99.96 percent coverage of planned land mass targets, with many areas imaged more than once.
      False-color image generated from SRTM data of the island of Oahu. False-color image generated from SRTM data of Mt. Cotopaxi in Ecuador, the tallest active volcano in the world. During the 11-day mission, SRTM collected more than one trillion data points, generating 12.3 terabytes of 3-D data of the Earth. Earnest Paylor, SRTM program scientist at NASA Headquarters in Washington, D.C., called the mission “a magnificent accomplishment.” He cited that SRTM imaged by radar equatorial regions of the Earth previously unmapped due to constant cloud cover. 

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    • By NASA
      On Feb. 8, 2010, space shuttle Endeavour began its 24th trip into space, on the 20A assembly mission to the International Space Station, the 32nd shuttle flight to the orbiting lab. The STS-130 crew included Commander George Zamka, Pilot Terry Virts, and Mission Specialists Kathryn Hire, Stephen Robinson, Nicholas Patrick, and Robert Behnken. During the nearly 14-day mission, they worked jointly with the five-person Expedition 22 crew during nearly 10 days of docked operations. The mission’s primary objectives included delivering the Tranquility module and the cupola to the space station, adding 21 tons of hardware to the facility. Behnken and Patrick conducted three spacewalks to aid in the installation of Tranquility.  

      The STS-130 crew patch. Official photograph of the STS-130 crew of Nicholas Patrick, left, Terry Virts, Robert Behnken, Kathryn Hire, George Zamka, and Stephen Robinson. The International Space Station 20A assembly mission payload patch.  In the Vertical Assembly Building at NASA’s Kennedy Space Center in Florida, workers prepare to lift Endeavour to mate it with its external tank and solid rocket boosters. Space shuttle Endeavour rolls out of the assembly building for its journey to Launch Pad 39A. The STS-130 astronauts leave crew quarters for the ride to Launch Pad 39A. Liftoff of space shuttle Endeavour on STS-130. Endeavour rolled out to Launch Pad 39A on Jan. 6, 2010, targeting a Feb. 7 launch. The crew arrived at NASA’s Kennedy Space Center in Florida on Feb. 3 to prepare for launch. Inclement weather delayed the initial launch attempt by 24 hours. On Feb. 8, at 4:14 a.m. EST, space shuttle Endeavour lifted off, carrying its six-person crew. The flight marked Robinson’s fourth trip into space, previously serving as a mission specialist on STS-85, STS-95, and STS-114, Zamka’s, Hire’s, Patrick’s, and Behnken’s second time in space, having flown on STS-120, STS-90, STS-116, and STS-123, respectively, while Virts enjoyed his first taste of weightlessness. 

      STS-130 Commander George Zamka, left, Mission Specialist Stephen Robinson, and Pilot Terry Virts on Endeavour’s flight deck on the mission’s first day in space. The shuttle robotic arm grasps the Orbiter Boom Sensor System for the wing leading edge inspection. Endeavour as seen from the space station during the rendezvous. View of the space station from Endeavour during the rendezvous. After reaching orbit, the astronauts opened the payload bay doors, deployed the shuttle’s radiators, and removed their bulky launch and entry suits, stowing them for the remainder of the flight. They spent six hours on their second day in space conducting a detailed inspection of Endeavour’s nose cap and wing leading edges, taking turns operating the shuttle remote manipulator system, or robotic arm, and the Orbiter Boom Sensor System.  
      On the mission’s third day, Zamka assisted by his crewmates brought Endeavour in for a docking with the space station. During the rendezvous, Zamka stopped the approach at 600 feet and completed a pitch maneuver so astronauts aboard the station could photograph Endeavour’s underside to look for any damage to the tiles. Zamka then manually guided Endeavour to a docking at the Pressurized Mating Adapter-2 attached to the Harmony module. After docking, the crews opened the hatches and the five-person station crew welcomed the six-member shuttle crew. Patrick and Expedition 22 Flight Engineer Timothy “T.J.” Creamer used the space station robotic arm to remove the inspection boom and hand it off to the shuttle arm operated by Hire and Virts. At the end of the day, Behnken and Partick entered the station’s airlock, reduced its pressure and breathed pure oxygen for an hour before and an hour after sleep to rid their bodies of nitrogen to prevent the bends. 

      Transfer of the Tranquility and cupola modules from the space shuttle to the space station. Robert Behnken, left, and Nicholas Patrick during the mission’s first spacewalk. STS-130 astronauts Stephen Robinson, top left, and Terry Virts and Expedition 22 Flight Engineer Soichi Noguchi of JAXA (Japan Aerospace Exploration Agency) in the newly installed Tranquility module. Nicholas Patrick, left, and Robert Behnken during the mission’s second spacewalk. The astronauts completed the major transfer activity of the mission on flight day five, a highly choreographed spacewalk and robotics effort to move the Tranquility and cupola modules from the shuttle to the station. Behnken and Patrick exited the airlock to begin the mission’s first excursion, first venturing to the shuttle payload bay to remove launch locks from Tranquility. Virts and Hire used the station arm to remove the joined modules from the payload bay and attach it to the Unity module’s port side. Behnken and Partick connected temporary heater and data cables to the new module. This first spacewalk lasted six hours 32 minutes. The next day, the joint crews began outfitting Tranquility and preparing to relocate the cupola from the end of the module to its Earth-facing port. 
      On the mission’s seventh day, some of the astronauts continued outfitting and configuring the new modules. In the meantime, Behnken and Patrick stepped outside for a five-hour 54-minute excursion, to install ammonia coolant loops and thermal blankets to protect the ammonia hoses, and outfitted Tranquility’s Earth-facing port to accept the cupola. 

      Relocation of the cupola to Tranquility’s Earth-facing port. Kathryn Hire, left, Terry Virts, and Expedition 22 Commander Jeffery Williams operate the space station’s robotic arm to relocate the cupola. During the mission’s third spacewalk, Nicholas Patrick, left, and Robert Behnken remove thermal blankets from the cupola. Terry Virts, left, and Jeffery Williams in the cupola after opening the windows for the first time. The next day, Hire and Virts, assisted by Expedition 22 Commander Jeffery Williams, used the station’s robotic arm to relocate the cupola. On flight day 9, Behnken and Patrick operated the station arm to relocate the Pressurized Mating Adapter-3 from Harmony to Tranquility. The crews continued internal cargo transfers and began outfitting the cupola.  
      On the mission’s 10th day, Patrick and Behnken completed their third and final spacewalk. During the five-hour 48-minute excursion, they removed thermal blankets and launch locks from the cupola, installed handrails, connected the second cooling loop on Tranquility, and connected heater and data cables. Inside the cupola, Hire and Virts installed the robotics workstation. Across their three spacewalks, Behnken and Patrick spent 18 hours 14 minutes outside. 

      Stephen Robinson, left, Soichi Noguchi of JAXA (Japan Aerospace Exploration Agency), and Nicholas Patrick transfer an environmental control system rack into Tranquility. George Zamka cuts the ribbon to officially open Tranquility for business, as Jeffery Williams looks on. The 11 members of STS-130 and Expedition 22 pose for a final photograph before saying farewell. The STS-130 crew poses in the cupola. Fisheye lens view of the two crews enjoying a meal together. The crews spent flight day 11 outfitting Tranquility with systems racks and other equipment moved from the Destiny U.S. Laboratory module. Virts finished installing robotic workstation equipment in the Cupola. Behnken and Partick transferred their spacesuits back to the shuttle for return to Earth. The crew received a phone call from President Barack Obama and several schoolchildren. Zamka and Virts used the shuttle’s thrusters to reboost the space station.  
      The next day, after holding a news conference with reporters on the ground, shuttle commander Zamka and station commander Williams held a ribbon-cutting ceremony to formally declare Tranquility and the cupola open for business. After a final meal together, the two crews held a farewell ceremony, returned to their respective spacecraft, and closed the hatches.  

      The space station seen from Endeavour during the fly-around with the Tranquility and cupola modules. Endeavour as seen from the space station during the fly-around, with a now empty payload bay. Endeavour touches down at NASA’s Kennedy Space Center in Florida. Workers ensure that Endeavour is safe after landing. The STS-130 astronauts pose on the runway at NASA’s Kennedy Space Center in Florida. The welcome home ceremony for the STS-130 crew at Ellington Field in Houston. On flight day 13, with Virts at the controls, Endeavour undocked from the space station, having spent nearly 10 days as a single spacecraft. The astronauts used the shuttle’s arm and boom sensors to perform a late inspection of Endeavour’s thermal protection system. On flight day 14, Zamka and Virts tested the orbiter’s reaction control system thrusters and flight control surfaces in preparation for the next day’s entry and landing.  
      On Feb. 22, Hire and Robinson closed Endeavour’s payload bay doors. The six astronauts donned their launch and entry suits and strapped themselves into their seats. Zamka and Virts fired Endeavour’s two Orbital Maneuvering System engines to bring them out of orbit and Zamka guided Endeavour to a smooth touchdown at Kennedy’s Shuttle Landing Facility. The landing capped off a successful mission of 13 days, 18 hours, six minutes and 217 orbits of the Earth. Workers at Kennedy towed Endeavour to the processing facility to prepare it for its next and final flight, STS-134 in May 2011, and the astronauts returned to Houston for a welcoming ceremony at Ellington Field. 
      Watch the crew narrate a video about the STS-130 mission.  

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