ESA : Efficiency of satellite telecommunications for civil protection agencies

17 December 2007
Enhancing interoperability during European civil protection operations is the objective of an ESA project named Decision. In the context of this project, field trials were held in Chartres, France, focusing on satellite solutions to improve cooperation between civil protection agencies in crisis theatres - whether they occur in Europe or outside.

The 'Decision' (DEvelopment of CIvil protection Satellite communication services: enhancing Interoperability during deployments Outside Europe - also referred to as 'Multinational Telecoms Adaptor') Project aims to increase the efficiency of co-operation between different national civil protection units working within the same foreign crisis theatre, and between members of national teams.

The demonstration covered two intervention scenarios. The first focused on a national situation where an industrial disaster has occurred and, as a consequence, the terrestrial communications infrastructure has been destroyed. In this instance, telecommunications satellite links are used to support coordination between the command post in the field and the regional crisis operations centre.

The second scenario dealt with an intervention outside Europe (such as an earthquake or a tsunami) involving a number of different civil protection agencies. For international disasters, rescue activity coordination needs to be performed between units in the field, as well as between national centres in Europe. In such a situation, telecommunications satellites are needed so as to ensure, on the one hand, communications between field units and, on the other hand, between those units and their national centres.

The Chartres trial allowed the validation of the satellite multi-adaptor use concepts that are applicable both in a national and an international context. It also helped to assess the added value of the multi-adaptor in a joint operation by different civil protection agencies working within the same foreign crisis theatre.

The involvement of civil protection agencies as end users is of primary importance since, by its nature, the project has a user-need oriented approach rather than a technology-push one.

The field trial was conducted with a cooperative spirit and a complementary contribution, through which fruitful results and end-user feedback were collected. This will lead to the definition of new perspectives and extensions of the current work.

The results truly demonstrated the need for adapted tools such as the Multi-Service Adaptor Communication Facilities, and some tracking facilities. These technical assets can ease the work of agencies in case of emergencies and also show the importance of developing interoperability solutions adapted to in-the-field needs and constraints.

The field trial benefited of the attendance and involvement of the French authorities and the French Civil Protection Agency (Direction de la Défense et de la Sécurité Civiles - DDSC), the German Technical Relief Agency (Technisches Hilfswerk - THW), the Belgian Civil Protection Agency, and the Austrian Civil Protection Support Unit.

Funded by ESA, the Decision consortium is composed of Infoterra France, the project lead, TRADIA Spain, Astrium Satellites France, EADS Secure Networks France and Skysoft of Portugal.

In the civil protection field, ESA's activities are now focused on drawing together the views and expertise of all European civil protection agencies, to define their requirements and assist them in federating and articulating their demand for satellite services. To this end, the European Commission and ESA have set up a tailored work plan for promoting satellite-based services of direct benefit to European civil protection agencies. The demonstration held in Chartres was a key milestone in this strategic, user-driven effort.

ESA : ESA and EC take major step forward in GMES

19 December 2007

ESA and the European Commission have signed a €48 million grant that will allow the space agency to ensure the coordinated and timely supply of satellite-based Earth Observation data for the preoperational phase of GMES from 2008 to 2010. The signing of the grant marks the first real cooperation between the two in the GMES framework.

The GMES (Global Monitoring for Environment and Security) programme is a European Union-led initiative in partnership with ESA to combine ground- and space-based observations to develop an integrated environmental monitoring capability.

ESA’s role within GMES is to coordinate and implement the dedicated GMES Space Component, which involves developing the five Sentinel satellites, and Ground Segment and to coordinate data access to the Sentinels and to other missions mainly from ESA Member States which contribute to fulfilling of the GMES requirements.

Following the signing of the GMES Space Component Data Access (GSC-DA) grant, European Commission (EC) Vice-President Günter Verheugen, who is responsible for enterprise and industry policy, said: "Globally, changes in environmental conditions lead to increased risks for economical, social and political stability, which further affect European security."

“Coordinated, comprehensive and sustained global monitoring of the Earth system is one of the key factors to respond to this challenge. GMES is the European solution for the needs of citizens in Europe to access reliable information on the status of their environment."


Dr Volker Liebig, Director of ESA’s Earth Observation Programme, signed the agreement on behalf of ESA. "The data access grant is the first step of a wider GMES cooperation with the EC, using ESA's 30 years of experience in collecting and distributing necessary Earth Observation data to users," Liebig said.

The data access grant will support the GMES services, which today include three fast-track services focusing on land, marine and emergency, two pilot service projects focusing on security and atmospheric composition, as well as downstream and other public GMES-related services.

The data access grant considers the EO data needs from the GMES services and covers the analysis of the services requirements, the negotiation of data access agreements with contributing missions, as well as the development and pre-operations of coordinating functions linking EO data providers with service providers.

Under the grant, ESA will coordinate the data provision activities from the EO contributing missions and will act as Data Provider for its own missions as well as its Third Party Missions.

ESA : ESOC 40th anniversary event marks history, emotion, future

ESOC retirees gather for the on-stage finale

19 December 2007
ESOC's 40th anniversary event on 18 December included history, emotion and expansion for the future as past and present personnel joined guests from across Europe's space community to celebrate.

The event showcased 40 years of successful spacecraft operations at ESOC, and was attended by over 1200 current and retired ESA staff and contractors and guests from Darmstadt, the Hessen region, Germany and numerous ESA Member States.

The highlight of the evening was a rousing on-stage performance including some 50 retirees representing, collectively, many centuries of operations experience and expertise.

	41-year-vetran Siegmar Pallaschke recounting ESOC's early days

Senior guests support ESOC

The event was hosted by Gaele Winters, ESA's Director of Operations and Infrastructure and Head of the ESOC establishment, who, together with Jean-Jacques Dordain, ESA's Director General, welcomed Dr Joachim Würmeling, Administrative Secretary of State in the Federal Ministry of Economics and Technology and Roland Koch, the Prime Minister of the State of Hessen.

Prof. Dr Johann-Dietrich Wörner, Chairman of the Executive Board of the German Aerospace Center (DLR), and Walter Hoffmann, Lord Mayor of the City of Darmstadt rounded out the senior invitees, all of whom gave addresses strongly endorsing ESOC as Europe's and Germany's 'Gateway to space'.

The evening included ESA's Space Show, a fantastic virtual voyage through our solar system highlighting space 'made in Europe' and featuring images, multimedia and science results from numerous ESA missions - most of which were controlled from ESOC.


With an eye to the future, the evening also included the signing of the formal agreement to expand the ESOC establishment through a grant of land provided by the government of Germany.

Universe Today : Galactic Black Hole Fires a Jet at a Nearby Neighbour

Written by Fraser Cain

Ouch, that's going to leave a mark. A new photograph captured by NASA's Chandra X-Ray Observatory shows a powerful jet blasting out of one galaxy, and colliding with another. As the jet tears through the galaxy, it could have serious implications for planetary formation, and trigger a wave of new star formation.

The image contains two galaxies, collectively known as 3C321, in orbit around one another. X-ray images from Chandra show that they both have supermassive black holes at their centres.

The black hole in the larger galaxy is actively feeding, and has an enormous jet of radiation and material blasting out into space. Unfortunately, the smaller galaxy has gotten caught right in the crossfire of this jet.

"We've seen many jets produced by black holes, but this is the first time we've seen one punch into another galaxy like we're seeing here," said Dan Evans, a scientist at the Harvard-Smithsonian Center for Astrophysics and leader of the study. "This jet could be causing all sorts of problems for the smaller galaxy it is pummeling."

So what kinds of problems? For starters, the jet has a tremendous amount of radiation, especially high-energy X-rays and gamma-rays. An ongoing blast of this radiation could strip away planetary atmospheres and blow away newly forming stellar nurseries. In other cases, the jet could cause a cloud of gas and dust to collapse in the first place, setting the stage for new star formation.

Since the two galaxies are only 20,000 light years apart - the same distance of the Solar System to the middle of the Milky Way - the effect of the jet will be extreme. One bright part of the image shows where the jet is colliding with the galaxy, and then getting disrupted and deflected away.

This event is probably very short-lived. Astronomers estimate that the jet only began impacting the galaxy about a million years ago; a blink of the eye in cosmological terms.

Original Source: Chandra News Release

ESA : Final preparations for first human-rated spacecraft to be lauched from Europe's Spaceport

Two halves of the ATV are mated ready for launch

18 December 2007
For the first time in 40 years of space activities, a silent revolution is taking place at the European launch site in Kourou. Jules Verne, the first human-rated spacecraft to be launched from Europe's Spaceport, is being prepared for launch.

The 48 m³ pressurised module of the largest, most complex automated spacecraft ever developed in Europe has been inspected and closed, fulfilling the most stringent rules of human spaceflight.

Three days later, the two halves of the 20-tonne Automated Transfer Vehicle (ATV) – the avionics/propulsion module and the pressurised cargo carrier – were mated ready for its launch, scheduled for February 2008, to re-supply the International Space Station (ISS).

“In order to eliminate any risk of disease or contamination for the astronauts on board the ISS, we have disinfected all the surfaces inside the pressurised module with pure hydrogen peroxide. Even if it is launched unmanned, ‘Jules Verne’ respects all the human spacecraft safety requirements. This also applies to the 7 tonnes of cargo carried into orbit”, said Patrice Amadieu, ESA’s ATV Deputy Project Manager.

	Loading dry cargo into Jules Verne ATV

Over five days, the interior of the cabin has been first disinfected, filled with approximately 1300 kg of ‘dry cargo’ such as food (500 kg), clothing (80 kg) and spare parts, and then disinfected a second time. Afterwards, experts from ESA, NASA and the world-famous Institut Pasteur’s laboratory, through its branch in French Guiana, have taken surface samples inside the ATV cabin for bacteriological analysis.

“Before closing the aft rear door of the pressurised module [through which the cargo has been loaded], we inspected one last time the entire cabin to be sure that everything was secured for the launch and safely placed where the ISS crew will expect the different items to be. After working for seven years on the programme, it was a special feeling to be the last person inside Jules Verne before it is launched into orbit”, said Charlotte Beskow, ESA engineer in charge of on-orbit crew operations.

Antoine Stevens (left) and Pierre Rebeyre (right) have taken water samples

Tanking of ‘Russian’ water

Last week, with the technical support of Thales Alenia Space in Turin and flown in from Italy, the ATV’s tanks were filled with about 268 litres of drinking water for the ISS astronauts. This is the municipal water of Turin (Italy) that has been treated according to Russian standards. Once in orbit, the water will be transferred via hoses to small portable containers or to the main tank on the Russian Service Module, where ‘Jules Verne’ will be docked for up to four months.

“It took about five hours to tank the water on board. The fact that for the first time drinking water will be carried into orbit by a European cargo spaceship for the ISS crew brings a great sense of satisfaction”, said Pierre Rebeyre, ESA expert for water quality control and Life Support System Development.

	Two halves of the ATV are mated ready for launch

The ATV can deliver to the ISS water either in compliance with the standards of NASA or with those of the Russian State Space Agency Roscosmos, but the ISS partners have decided Jules Verne will only bring the Russian water type.

Roscosmos standards call for water with certain amounts of minerals, such as calcium, magnesium and fluoride, and disinfection with silver obtained via electrolysis. By contrast, the NASA potable standard requires water with a low dry residue, such as the one produced through reverse electrolysis process by fuel cells on board the NASA Space Shuttle, and disinfection with iodine.

Closing the ATV's pressurised module

Synthetic air inside the cabin

Once the ATV's pressurised module is closed and sealed, its air can be purged and replaced by pure synthesised air. The main purpose of this operation is to ensure that the astronauts breathe clean air, free from particles, bacteria or microbes and unaffected by off-gassing from the several tonnes of cargo.

Off-gassing poses a serious concern in space because cargo objects emit odours and odourless gases that can endanger the cabin environment. Because no windows can be opened in space, the climate of the ISS and space vehicles are delicately checked and balanced. The air inside the pressurised module will be regularly analysed until launch by ESA, NASA and Institut Pasteur experts to be sure that cargo off-gassing will not alter the quality of the air brought into orbit and then mixed with the Space Station atmosphere.

Final steps

Implementing a work schedule of two eight-hour shifts and sometimes three shifts for six days a week, the ATV campaign, which started in early August, solved all technical issues. The two major pieces of the ATV, a pressurised payload unit and an avionics/propulsion unit, were carefully ‘mated’ for the last time in one piece on 15 December in the Spaceport's giant integration hall. In this final launch configuration, the ATV is the size of a double-decker London bus.

As the year 2008 approaches, Jules Verne ATV will be transferred to the filling area in the restricted propellant zone of building S5-B. In the first days of February, the cargo vessel will be transferred to a different site for integration atop a special Ariane 5 launcher. The launch and maiden voyage to the International Space Station is scheduled on the first Ariane 5 flight of the new year in February 2008.

ESA : Christmas greetings from Venus – with a new educational film

‘A breath of Venus’ - an educational film

18 December 2007
What is the link between Earth and Venus? Find out with this new educational film, where scientists walk you to enchanting places on Earth to unveil the secrets of Venus.

	A breath of Venus

The film consists of four chapters. In the first and main chapter, ‘A breath of Venus’, two scientists climb atop one of the most famous active volcanoes on Earth. From the island of Vulcano, Italy, the scientists talk about Venus’ impressive green-house effect, give glimpses of how volcanism may work at Venus as compared to Earth, and illustrate the principles used for such investigations on other planets.

The three additional chapters of the film bring our attention to other fascinating aspects of Venus exploration – all addressed relentlessly by ESA’s Venus Express.

A story of Deuterium and Hydrogen

From a sandy beach in the Netherlands, ‘A story of Deuterium and Hydrogen’ takes us through the story of the fate of water on Venus. Did Venus host oceans in the past? If yes, where has this water gone now?

	A question of temperature

In ‘A question of temperature’, a scientist climbs an apple tree and tells us how to calculate the global temperature of a planet. He talks about why planetary temperatures are important for the overall climate balance, related to the green-house effect - the phenomenon at work on both Earth and Venus.

A look at operations

‘A look at operations’ unveils the secrets behind spacecraft operations, and tells us about the complex job engineers perform as they translate scientific objectives into commands for the Venus Express spacecraft.


Click on any of the images in this article to go to the download page.

ESA and Venus Express take this chance to wish you a merry Christmas. Enjoy watching!

Universe Today : Enceladus: Cold Moon With a Hot Spot

Written by Nancy Atkinson

Saturn’s tiny moon Enceladus is a cold and icy place. But somehow, there’s enough heat being generated on Enceladus’ south pole to eject plumes of ice and vapor high above the moon. These plumes are extremely intriguing to the Cassini mission scientists and they want to know more about this hot spot on a very cold moon. In fact, Enceladus has become a major priority for study by the Cassini team and they are anticipating learning more about the moon in an upcoming fly-by.

The temperature at Enceladus' south pole is about -220 degrees Celsius, but the hot spot is at least 100 degrees warmer. The leading model for the cause of the plumes on Enceladus is that the moon’s tides cause its crust to ratchet, or rub back and forth, in a set of faults near the south pole. The forces between Enceladus, the big planet Saturn and another moon, Dione cause what’s called dynamical resonance, and Enceladus is continually squeezed under this gravity field. This process creates a small hot spot, in relative terms, for an icy satellite.

Cassini has actually flown through the plumes, giving scientists a glimpse of the plume’s make up.

“The plume particles are like smoke, ice smoke, “said William B. McKinnon, professor of earth and planetary sciences at Washington University in St. Louis. “If you were standing on Enceladus’ surface you wouldn’t even be able to see the plumes. The particles are just larger than the wavelength of light, about one-thousandths of a millimeter. Most icy bodies of this size are geologically inert, but this is a clear indication of geological activity. Cassini has found active venting of water vapor. This leads to scientifically intriguing speculations and questions.”

The scientists are pondering if Enceladus has active ice volcanism, and if so, is it due to ice sublimating, like a comet, or due to a different mechanism, like boiling water as in Old Faithful at Yellowstone. Even though there may be water on the moon, McKinnon doesn’t believe there is the possibility of life on Enceladus. This is because measurements made from Earth don’t indicate there is enough sodium present in the plumes to warrant the “life” question. “The emerging view is that there’s not obvious evidence for a subterranean ocean in contact with rock, no boiling or venting,” said McKinnon.

The Cassini science team has made Enceladus a major priority and there will be seven additional close fly-bys of the moon by the spacecraft through mid-2010 (provided the mission is extended to that period.) The next fly-by will be on March 8, 2008 and Cassini will approach Enceladus at an incredibly close 25 km in altitude at the low latitudes and fly over the south pole at 580 km altitude. The spacecraft will actually fly through the plumes and should be able to take high-phase images of the plumes, map the temperatures of that region, search for any activity at other latitudes as well as image other interesting features on Enceladus, such as “tiger-stripe” –like fissures found near the south pole.

“We still can’t say how truly ‘hot’ the hot spots are,” said McKinnon. “We’ll probably learn this in March.”

Original News Source: Washington University Press Release

Universe Today : Mars at its Closest Approach

Written by Fraser Cain

Okay, now you can tell your friends and family that Mars is making its closest approach, and not August like that annual hoax email that goes around. This image of Mars, taken by the Hubble Space Telescope, was captured when the planet was only 88 million km (55 million miles) away from Earth. Their closest point occurs on December 18th at 1145 UTC (6:45 p.m. EST).

This close encounter between the Earth and Mars happens every 26 months. That's because Earth makes more than two orbits for every one Martian trip around the Sun. As the Earth catches up with Mars in orbit, the planet brightens in our skies until it becomes one of the brightest objects we can see.

Since both Earth and Mars have elliptical orbits, the point of their closest approach changes from year to year. Back in 2003, when that closest approach between Earth and Mars actually happened, the two planets were 32 million km closer (20 million miles) than today. (Of course, Mars never looked as large as the Moon in the sky, it was always just a bright red star.)

The image attached to this story was made up of a series of photographs captured by Hubble over the last 36 hours. They were then stitched together on computer to make up this composite photograph.

The large triangular dark shape on Mars is Syrtis Major, and the region on the left is called Sinus Meridani. That's roughly where NASA's Opportunity rover is currently rolling across the Martian landscape.

When Hubble took this photograph, the planet was largely free of the dust storms that plagued the Mars rovers earlier this year. Although, you can see clouds near the northern and southern poles.

Original Source: Hubble News Release

Universe Today : Mysterious Explosion Comes Out of Nowhere

Written by Fraser Cain

When astronomers find a gamma ray burst, they can usually locate the culprit's home galaxy. But in the case of an explosion that went off earlier this year, there's no galaxy to be found - even with the most powerful telescopes on Earth.

The gamma ray burst GRB 070125 was first detected on January 26th, 2007 by NASA's Swift telescope in the constellation Gemini. One of the brightest bursts of the year, astronomers scrambled to observe the explosion and then the slowly fading afterglow.

Gamma ray bursts occur when a massive star runs out of fuel. Without the light pressure, the star collapses inward on itself, turning into a black hole. This newly formed black hole spins at an enormous rate, generating enormous magnetic fields. These fields catch infalling material and spew it out again into powerful jets. And it's those jets where the burst comes from.

One of the normal activities in observing GRBs is the identify the host galaxy so that astronomers can measure its distance. It's also important to know what kind of galaxy the burst exploded within to better understand the kinds of environments can lead to these massive stars.

In the case of GRB 070125, though, no originating galaxy was obvious. Astronomers from Caltech/Penn State used the 60-inch Palomar Observatory to watch the afterglow, and then called in the even larger Gemini North and Keck 1 telescopes, located on Hawaii's Mauna Kea.

Even with the power of Keck, they couldn't find a galaxy.

So how could you get a gamma ray burst without a galaxy? Astronomers know that colliding galaxies can throw off enormous tidal tails that stretch away for hundreds of thousands of light-years. The original star could have been within one of these tidal tails, many light-years away from its parent galaxy.

If their theory is correct, a long duration exposure from the Hubble Space Telescope should reveal the dim tidal tail.

Original Source: NASA News Release

Space.com : Spacewalkers Inspect Space Station's Solar Wing Joints

By Tariq Malik Staff Writer posted: 18 December 2007 12:51 p.m. ET

This story was updated at 3:00 p.m. EST.

Two spacewalking astronauts took a close look at a pair of balky solar array joints outside the International Space Station (ISS) Tuesday to help engineers on Earth draw up repair plans.

Expedition 16 commander Peggy Whitson and flight engineer Dan Tani found widespread contamination inside a massive gear that rotates both of the station's starboard solar arrays, but no sign of damage to a joint at the base of one of those solar wings, during nearly seven hours of orbital work.

"Hopefully we got a good amount of data for the folks on the ground," said Tani, who led the spacewalk, after the reentering station's Quest airlock.

Whitson and Tani began Tuesday's spacewalk at 4:50 a.m. EST (0950 GMT), marking the fourth for their Expedition 16 mission. The excursion was initially scheduled as an extra spacewalk during NASA's STS-122 mission aboard the shuttle Atlantis, but the flight's planned December launch was thwarted twice by faulty fuel tank sensors.

As the Expedition 16 crew worked in orbit high above Earth, engineers at NASA's Kennedy Space Center in Florida fueled Atlantis' external tank to test the erratic sensors. Shuttle workers hoped to recreate, and then isolate, persistent glitches with the fuel gauge-like sensors in order to proceed with Atlantis' rescheduled Jan. 10 launch.

Fact-finding inspection

Whitson and Tani focused most of their spacewalk on a massive gear designed to rotate the station's starboard solar arrays like a paddlewheel to keep its power-generating wings continuously facing the sun.

Engineers will use the astronauts' findings as a reference for any plans to repair the joint's bearings, motors and metal race ring. Solving the station's solar array joint woes is vital to allow the outpost to support the addition of a large Japanese-built laboratory and other modules, mission managers have said.

"We didn't find anything that stood out," said NASA's space station program manager Mike Suffredini after the spacewalk. "It would be really nice if something stood out and said, 'Hey, I'm the cause of your problem,' and we didn't get that. But we do know more about the condition of the ring."

Tani first discovered metal grit inside the joint, known as a Solar Alpha Rotary Joint (SARJ), during a late October spacewalk after flight controllers noticed odd vibrations and power spikes in the mechanism's telemetry. A second inspection by spacewalkers last month confirmed the contamination, which Tani and Whitson found to be widely distributed around the 10-foot (3-meter) wide joint during today's excursion.

"You can see the motion of the gear because the debris is kind of walking across the housing," said Tani, adding that magnetized metal shavings appeared to walk end-over-end on one of the SARJ motors. "It's hilarious...it's animated, like they're alive. They're like ants."

The spacewalkers retrieved a suspect set of bearings, one of 12 on the joint, which may be responsible for the contamination. They also used orange Kapton tape to take samples of the metal grit and clean the SARJ gear's damaged metal race ring.

"I am getting almost all of the debris off," Whitson said. "It seems less splotchy."

Using a mirror, Tani and Whitson looked inside the SARJ gear to find that two sides of its three-sided race ring were untouched by damage, boosting hopes that engineers can find a way to continue using the joint in short spurts while continuing to study the glitch.

"If we can figure out to live with this, maybe roll on it for awhile when we have to...it gives us more time to figure out root cause and figure out what the real issue is," Suffredini said. By taking that extra time, engineers could determine whether a major switch to a backup race ring, which could potentially take up to four spacewalks and be performed during a fall 2008 space station mission, will be required, he added.

Tuesday's spacewalk marked the 100th outside the ISS and the 23rd this year alone, tying the all-time record for excursions in a single year. The spacewalk was the fifth career outing for both Tani and Whitson, who set a new world record during the outing for the most spacewalking time for a female astronaut.

"Congratulations, there is no pressure now because you are the queen of EVA," Mission Control told Whitson, using NASA's abbreviation for extravehicular activities.

"It's just being in the right place at the right time," replied Whitson, who is the space station's first female commander and beat NASA astronaut Sunita Williams' benchmark of 29 hours and 17 minutes to nab the title.

Hunting for damage

In addition to their SARJ joint inspection, the spacewalkers also surveyed cables and other hardware for a beta gimbal joint that swivels one of the station's starboard solar wings on a different axis from the SARJ. The joint suffered triple electrical failures on Dec. 8, prompting concerns on Earth of a possible micrometeorite strike.

"Everything I can see is nominal," Tani said. "There is no damage, no frays that I can see."

Despite her bulky NASA spacesuit, Whitson squeezed herself inside the station's backbone-like truss to reach the gimbal joint's power cables. Mission controllers warned her that it would be a tight fit, prompting a laugh from the spacewalker.

"Does this [spacesuit] make me look fat," she joked.

Space station managers said they are now confident that the gimbal joint's glitch lies in its motor box. A spare for the unit is aboard the ISS and Tani is trained to replace the motor.

Whitson ended Tuesday's spacewalk with 32 hours and 36 minutes of spacewalking time under her belt across five career excursions. Tani, meanwhile, ended with 32 hours and one minute as he concluded his fifth career spacewalk.

• VIDEO: ISS Commander Peggy Whitson Takes Charge
• IMAGES: The STS-120 Shuttle Mission from Orbit to Earth
• SPACE.com Video Interplayer: NASA's STS-122: Columbus Sets Sail for ISS