DISCOVERY REBORN AFTER EASTER – MISSION TO EDUCATE

The Space Shuttle Discovery started a new mission after its retirement. She will become an engine of Imagination, Inspiration and Education in her new home at the Smithsonian’s National Air and Space Museum in Chantilly, Virginia.

Gen. Jack Dailey, director of the museum welcomed the new arrival on 19 April 2012. A large audience attended the ceremony, in which the shuttles Enterprise and Discovery were united. Among the attendees were 15 of the 32 commanders and many of the crews that had the privilege to ride on the space shuttle during her 30 years of space exploration.

This iconic vehicle will now join other marbles of technology and flight at one of the most prestigious museums in the world.

Discovery was put together in 4 years at the Shuttle Factory in Palmdale, California, from where it was delivered to NASAs Kennedy Space Centre in Florida in November 1983. She flew her first mission, STS-41, on 30 August 1984 (STS stands for Space Transportation System).

The shuttle completed 39 missions, spent 365 days in space, orbited the Earth 5,830 times, and travelled 238 million kilometres (148 million miles).

During her missions, she released Hubble Telescope in 1990 (mission STS-31), launched many satellites, carried many research laboratories, was the first shuttle to reach and dock with the International Space Station in 1999 (STS-96), and in her last mission carried the first experimental robot “Robonaut 2.”

Discovery’s last touchdown was on runway 15 of Kennedy Space Centre in Florida, at 16:57 UTC on Wednesday 9th March 2011, marking the conclusion of Mission STS-133. The last crew on board was composed by: Commander Steve Lindsey, pilot Eric Boe, and mission specialists Nicole Stott, Mike Barratt (medic), Steve Bowen and Alvin Drew.

After a year of preparations for exhibition, Discovery was flown mounted atop NASA's Shuttle Carrier Aircraft (SCA), a modified Boeing 747 jetliner, from Kennedy Space Centre in Florida to Washington Dulles International Airport in Sterling, Virginia on 18 April 2012. The next day she was towed by road (courtesy of Signature Flight Support and Swissport) to its final destination at the Smithsonian’s Udvar-Hazy Centre.

Among the speakers at the ceremony was Senator John Glenn, who in November 2011 received the highest civilian award bestowed by Congress, The Congressional Gold Medal for his pioneering contributions to space exploration. He flew to orbit for the first time in 1962 on board Mercury Friendship 7 and returned to space at the age of 77 on board Discovery as Payload Specialist in 1998 (STS-95). He reminded the audience of the history and highlights of the shuttle and talked about the future of this vehicle, which will become a symbol of achievement and inspiration for future generations, representing optimism, hope, challenge, leadership and aspiration to explore and to excel.

Astrophysicist Dr. France Cordova, former chief of research at NASA, currently president of Purdue University in West Lafayette, Indiana and Chair of the Smithsonian Board of Regents, talked about the contribution of the university to the space program. This institution not only provided hundreds of engineers and scientists to NASA but 22 of their alumni went to space, including the first and last astronauts who went to the moon.

At the end of the ceremony, the official paper: “Certification of Retirement of Space Shuttle Orbiter Discovery (OV-103) & Acknowledgment of Transfer from NASA to the Smithsonian Institution”, was signed by the three authorities: J R Dailey, Director of the National Air and Space Museum; Charles F. Bolden, Jr., Administrator of NASA (National Aeronautics and Space Administration) and G. Wayne Clough, Secretary of the Smithsonian Institution. Senator John H. Glenn, Jr. acted as witness.

So there you go Discovery, God Speed in your new mission, one that will touch generations to come. Thanks for the service to humanity and thanks to NASA and all those thousands of people involved in one way or another in turning the mankind dream of exploring space into a reality.

And this is only the beginning …

The crew that flew Discovery on her last mission

The crew of Mission STS-133 (24 February to 9 March 2011):
Commander Steve Lindsey, pilot Eric Boe, and mission specialists Nicole Stott, Mike Barratt (medic), Steve Bowen and Alvin Drew seen here before the launch of their mission. The bottom picture was taken when they met the President of the United States in May 2011.

Attending commanders

Karol Bo Bobko 1985 (STS-51-D), Joe Engle 1993 (STS-51-I), Mike Coats 1989, 1991 (STS-29 + 39 now director of Johnson’s Space Centre), Fred Gregory 1989 (STS-33), Bob Cabana 1992 (STS-53 now Director of Kennedy Space Centre), Ken Cameron 1993 (STS-56), Frank Culbertson 1993 (STS-51), Charlie Bolden 1990, 1994 (STS-31 + 60 now Administrator of NASA), Curt Brown 1997-98-99(STS-85 + 95 + 103), Scott Horowitz 2001 (STS-105), Steve Lindsey 2006 + 2011 (STS-121 + 133), Eileen Collins 1995 (STS-63), C J Sturckow, Alan Poindexter.

Speakers

References

¤ ‘NASA Transfers Space Shuttle to NASM’ (2012). NASA Channel. [Online]. Available here. (Accessed: 20 April 2012).
¤ Pearlman, R. (2012). ‘Space Shuttle Discovery Enters Smithsonian for Museum Display.’ Space.com [Online]. Available here. (Accessed: 20 April 2012).
¤ ‘Space Shuttle Discovery’ (2012). Wikipedia. [Online]. Available here. (Accessed: 20 April 2012).
¤ Renart (2011). ‘Discovery returns safely from her last flight’. [Online]. Available here. (Accessed: 20 April 2012).
¤ ‘World’s Greatest Piggyback Ride’ (2012). NASA. [Online]. Available here. (Accessed: 20 April 2012).

Images

¤ All images edited by ren@rt. Source: NASA.

MARS ROVER “CURIOSITY” - A SCIENCE LAB (MSL)

Mars is recognized by many scientists as humanity’s next point of exploration after the Moon. The next missions to our natural satellite will help build capabilities to eventually send humans to Mars.

NASA’s Jet Propulsion Laboratory (JPL) in collaboration with other space agencies around the world has been working in a new generation of Mars Explorer Rover named “Curiosity.” It launched flawlessly in a 9-month journey towards Mars on 26 November 2011 on board a United Launch Alliance Atlas V rocket.

Shortly after launch, March Science Laboratory (MSL) project manager Pete Thaisinger thanked the team at Kennedy Space Centre in Florida for a professionally smooth launch operation. He also thanked the 250 scientists at Jet Propulsion Laboratory for 10 years of work putting together this unique piece of equipment.

The panel at the post-launch conference also included John Grotzinger, Project Scientist from California Institute of Technology and Doug McCuisition, Director of the Mars Exploration programme from NASA. These representatives reminded the media that this is not a life detection mission but an intermediate mission between Mars Exploration Rover (MER) which was sent to detect water and future missions to detect life. This mission is about looking for ancient habitable environments, when circumstances in Mars were very different than what they are today; therefore, selecting the landing and exploration site was crucial for its prospects of success.

Launch of MSL on board an Atlas V Rocket
On 26 November 2011, a United Launch Alliance (ULA) Atlas V rocket launched successfully carrying the MSL.
The following two videos cover from Count-down to launch and separation of MSL.
Farewell “Curiosity,” God Speed on your 9-month journey to Mars!

The strategy to gather images will be different than that of previous rover missions. During the MER missions, scientist would receive all static images from the rovers, and from those, build a selection and decide the locations worth shooting with the panoramic camera. This time, Curiosity will take pictures and store them in a memory buffer, then only send a set of thumbnails for scientists to select a meaningful sub-set and later downlink only the chosen full resolution images. This will allow for more efficient use of the limited communication channels.

During the mission, scenarios will be carefully assessed and practice runs will be simulated on the twin version of the rover at JPL. After this training scientists will send precise commands for the execution of those complicated manoeuvres.

The cost of the programme was also discussed and the panel reasoned that this is a bargain of an investment as the cost is close to that of a modern movie, not to mention the thousands of jobs maintained and created around this endeavour. The benefits will be immense and only understood and valued by coming generations of humans. We must not forget that all the money that goes into the programme is spent on Earth, not on Mars.

Curiosity, the Rover

The name of the project is Mars Science Laboratory (MSL), an all-weather, all-terrain vehicle created with the purpose of exploring Mars looking for an answer of the age-old question: Was Mars ever capable of sustaining life?

This multinational rover was put together at the Spacecraft Assembly Facility of Jet Propulsion Laboratories in Pasadena, California. Space agencies of France, Russia, Canada and Spain built a number of instruments which form part of the payload of the vehicle.

The following list of facts provide an idea of the work involved in sending Curiosity to Mars. This is one of the most complex projects of JPL to date with surprising innovations resulting from the accumulated knowledge of the planet, aeronautics and space travel.

• MISSION: The mission of Mars Science Laboratory (MSL), aka the “Curiosity” rover, is to search areas of Mars for past or present conditions favourable for microbial life. It will search for potential locations, acquire samples, analyse them and send reports back to Earth.
• DURATION OF MISSION: One Martian year, this equals to 23 Earthly months until the planetary positions re-align and the crew can return home.
• DEPARTURE: Launch is scheduled for 25 Nov 2011 from Cape Canaveral, Florida, on an Atlas V 541 vehicle (rocket).
  This vehicle will place the spacecraft in orbit and use a slingshot effect to finally release it towards Mars.
  The MSL is at this stage surrounded by an engine that will provide propulsion and correct direction. This section has solar panels to top-up its energy requirements.
• ARRIVAL: The interplanetary journey will take eight and a half months. The expected date of arrival is 5th August 2012.
• LANDING: This ingenious and complex landing process aims to provide maximum protection to this new generation of rover.
  The entry capsule is fitted with tiles of a new ceramic material designed to efficiently shield it from the intense heat of entry as it plummets through the Martian atmosphere towards the ground at a speed of 19,300 km/h. At this speed it would reach the surface in 5-6 minutes and probably disintegrate.
  The capsule therefore needs to be slowed down.
  Friction against atmospheric particles is expected to reduce the capsule’s speed to 1,600 km/h. Soon after, a large supersonic parachute is deployed to slow down the lander even further.
  In the next stage called the Descent, a new aircraft, the Sky-Crane comes into operation, it will actively reduce the speed of the fall to tens of metres per second thanks to a set of 8 thrusters, which consume 400kg of propellant. The Sky-Crane then will find and hover over the landing site and slowly lower the rover with a 7.5m long bridal cable, until it touches the ground on its own wheels at a speed of 0.75m/sec. The Sky-Crane then flies away to land somewhere else completing its function.
• LOCATION: The selection of the landing site is crucial to maximise the chances of finding the right soil to examine. Considering that Mars is about 1/3 the size of the Earth, with a surface area similar to that of dry land on Earth, finding the right site for landing was a mission in itself.
  After 7 years of study of images sent by previous missions, a final spot was chosen from around 50 candidates. Curiosity will touch-down on a relatively flat zone inside the “Gale Crater,” close to the equator. This crater was possibly created by flow of liquid or possibly winds, the hills surrounding the valley seem to expose strata, ideal for gathering geological samples.
  There is a 5 km-high mountain nearby at the centre of the crater. The mission will attempt to climb up to the bottom 1/3 of the mountain
  in 2 years, reaching areas that look like clays and sulphurs.
• TRAVEL ON MARS: The Mars rover is expected to travel 5 to 20 km during the mission.
• WHO NAMED CURIOSITY?: The vehicle was named by Clara Ma, a 12-year-old student from Lenexa, Kansas after winning a Mars Science Laboratory rover-naming contest in 2009.
• BUILDING CURIOSITY: The MSL was built in a large clean room at JPL's Spacecraft Assembly Facility in Pasadena, California. In the clean rooms, all working engineers wear white "Bunny suits" that include booties and gloves to protect against Earthly contaminants. They also wear a grounding wire around the neck to prevent electrostatic discharge. Building in a clean room prevents contamination by biological particles, which may lead to false-positive results that invalidate findings. Clean rooms have a strict limit of tolerance of particles per cubic foot of air; the one at the assembly facility allows up to 10,000 particles greater than half a micron in size. To put this into perspective, a typical “non-clean” room may have 500,000 to one million particles per cubic foot of air.
• COMMUNICATIONS: Signals will be relayed by spacecraft orbiting Mars: NASA's Mars Reconnaissance Orbiter and Mars Odyssey spacecraft. In addition, messages will travel through NASA's Deep Space Network, an international network of antennas that support interplanetary spacecraft missions. Signals travelling at the speed of light (300,000 km/sec) are delayed by 10 to 20min due to the distance to Mars, which is another challenge for remote operations.
• SIZE:
  • Body: This is the largest Mars rover to date, twice the size of the last rover “Opportunity” and ten time the size of “Pathfinder”. It is as large as a Mini Cooper car with a height of 2.2m, a width of 2.7m and a length of 9m. It weights 900kg. Mostly made of aluminium, its suspension and spokes are made of titanium. It has a ground clearance of 60cm. The core structure is approximately 1 meter wide and long.
  • Arm: Curiosity is fitted with a single 2.2m long arm designed to manoeuvre a 30kg Turret.
    Located on the front panel, the arm provides the dexterity required to acquire material and feed it to the lab. It was constructed by the same Canadian company that made the arms of previous rovers.
  • Turret: This conglomerate of instruments contains drilling and collecting tools. The drill head is of Rotary-Percussive or Hammer-Drill type and is designed to drill holes of up to 5cm in depth and collect the dust from the centre and the periphery of the hole. In case of a broken or jammed drill-bit, it can drop the bit and replace it with another; it carries 2 spare drill-bits.
    If biological material were found, the rover has 5 red tiles of Organic-Check-Material, which are biologically-free blocks that can be drilled to compare results and rule out false-positives resulting from biological material being carried from Earth.
  • Wheels: The 6 wheels of Curiosity are made of aircraft-grade aluminium, they are 50.8 cm in diameter and 50cm in width. Each wheel has 1.27cm thread dents and holes that leave imprints in the soil for visual odometry. The rover has a wheel-base of 2.26m.
    The solid wheels were designed to roll over obstacles of up to 75cm in height. Aluminium was chosen because it is a strong, yet light material that can tolerate denting without impact to driving ability.
  • Capability: Top speed of 140metres/h. One horsepower. Its torque or ability to drive up slopes is 3000 ft/lb (500 ft/lb on each wheel, similar to that of an average car per wheel), this is very high because the vehicle will operate in very low temperatures of -10 to -26 Centigrade (-50 -80 F). Curiosity will travel at a very low speed but with a lot of power being able to drive up 30 degree slopes.
• POWER SOURCE: Unlike its predecessors that use solar panels, Curiosity has a Radioisotope Thermoelectric Generator (RTG) built by Boeing, which uses the heat generated by the natural decay of a small amount of Plutonium-238 and converts it to electricity. It generates about 110Watts of power continuously recharging a 40Amp battery. Plutonium’s capacity to generate energy is expected to decay in decades.
  Other spacecraft that use similar power source are: Vikings, Cassini, Voyager.
  The excess heat is used to warm up the vehicle through a network of heat exchangers or pipes, which can also be used to remove heat should it become too hot. The pipes contain Freon that circulates thanks to a pump to control the temperature, heating-up or cooling down the rover when needed.

SCIENCE PAYLOAD

1. Cameras
• Mast Camera (Mastcam): Two cameras for stereo imaging mounted on the Remote Sensing Mast: Telephoto, colour and video.
• Mars Hand Lens Imager (MAHLI): A magnifier tool capable of looking at samples in colour even in the dark using ultraviolet light. This is mounted on the end of the arm.
• Mars Descent Imager (MARDI): This camera will be activated shortly after the separation from the heat shield. It will take colour High Definition images at 5 frames per second all the way to the surface. After landing it is turned off and remain available in case it is required later. Some of the images acquired will be sent to Earth within the first 2 weeks and in a few months all the images will arrive to create a movie sequence of entry and descent.
2. Spectrometers
• Alpha Particle X-Ray Spectrometer (APXS) (in collaboration with Canada): Bombards a sample with Alpha particles or X-Rays to determine its composition.
• Chemistry & Camera (ChemCam) (in collaboration with France): A 2-piece instrument, one with a telescope. Uses a high power laser from 5m away that vaporizes the outer surface of the rock, then the camera's spectrometer analyses the resulting cloud of plasma to determine its chemical composition, this triage process singles out the interesting rocks to approach for sampling. A similar instrument is used on Earth to detect lead contents of wall paint.
• Chemistry & Mineralogy X-Ray Diffraction/X-Ray Fluorescence Instrument (ChemMin): This is an X-Ray diffraction pattern detector that processes samples to find component minerals. It vibrates the samples to operate.
• Sample Analysis at Mars (SAM) Instrument Suite: Looks for Organic molecules from collected samples. This will find out if there are traces of past microbial life by searching for chemical isotopes generated by biological processes. It also looks for methane, commonly produced by biological processes rather than chemical ones. This is very sensitive, capable of detecting methane in parts per trillion and can find even methane produced on the other side of the planet. This is the largest instrument on the rover, the size of a microwave oven. The samples are processed in a small oven that heats them up to 1000 degrees, which removes all volatile substances before they are passed to other instruments.
3. Radiation Detectors
• Radiation Assessment Detector (RAD): A radiation detector with dual purpose: It defines the radiation in the environment at the moment of measurement and calculates long-term patterns for future missions.
• Dynamic Albedo of Neutrons (DAN) (in collaboration with Russia): Detects sub-surface Hydrogen by bombarding the surface with a neutron generator and looks at reflected neutrons. Its purpose is to find Hydrogen or Water under the surface.
4. Environmental Sensors
• Rover Environmental Monitoring Station (REMS) (in collaboration with Spain): A weather station that detects atmospheric pressure, temperature, wind speed and direction and other meteorological measurements that will report back to earth in the future. These are mounted on booms or masts. Includes a UV detector.
5. Atmospheric Sensors
• Mars Science Laboratory Entry Descent and Landing Instrument (MEDLI): Determines atmospheric conditions and performance of the MSL during entry.

ChemMin and SAM analyse samples inside the rover
Pulverised samples are fed to a disk-shaped transparent chamber, of which various pairs are ready to rotate into position. The instruments analyse the material using X-Ray diffraction and determine patterns that represent chemical elements.

Watch the animation from Jet Propulsion Laboratory

Building the Mars Science Laboratory
The MSL Curiosity was built in a clean room at JPL's Spacecraft Assembly Facility. See the engineers wearing white "Bunny suits" to protect the rover from Earthly contaminants.

Curiosity Rover on Mars
In 2012 the Mars Science Laboratory “Curiosity” will rover on Mars, seeking chemical evidence of life and attempting to answer many scientific questions for the advancement of humanity into space.

Humans on Mars

In preparation to humans visiting Mars, NASA is planning on building capabilities that exceed those achieved by the Apollo programme. They will first send 4 people to the Moon for gradually longer stays, starting with one week and gradually progressing to up to 6 months.

When all the problems about living on an extra-terrestrial environment are solved in a near base like the Moon, which is only 3 days away, the next step will be a manned mission to Mars.

As stated by Richard Gilbrech (Associate Administrator for Exploration System, NASA) in 2008, initial missions to Mars are anticipated to take 3 crew astronauts in a 30 month mission. Starting with a 6 month journey, followed by a required 18 months stay on the surface until the planets align and the mission can embark on a similar length of journey back to Earth.

From this point of view, the International Space Station and the Moon are experiments to build capabilities for longer missions. They will require a global enterprise with immense investments of time, people and money.

On this mission, an unprecedented 1 ton of equipment will be landed on another planet. It is expected that by the time a human mission arrives in Mars, the volume of equipment required to land will have a weight of 40 to 60 tonnes; so far we do not have the technology to handle that weight.

Humans on Mars
Humans will eventually arrive in Mars and expand the horizons of space exploration.

References

¤ ‘The Moon and Mars - the next destinations for humans’ (2008). The 59th International Astronautical Congress, Glasgow, Scotland. [Online]. Available here. (Accessed: 06 November 2011).
¤ ‘Curiosity Rover, FAQ’ (2011). JPL. [Online]. Available here. (Accessed: 06 November 2011).
¤ Richard Cook ‘Mars Science Lab Curiosity’ (2011). Theodore von Karman Lecture Series at JPL. [Online]. Available here. (Accessed: 06 November 2011).
¤ ‘Mars Science Laboratory Curiosity Rover Animation’ (2011). JPL. [Online]. Available here. (Accessed: 07 November 2011).
¤ ‘Mars Science Laboratory Lifts Off for Red Planet’ (2011). JPL. [Online]. Available here. (Accessed: 27 November 2011).
¤ ‘MSL's Mars Trajectory Confirmed During Post-Launch Briefing’ (2011). JPL. [Online]. Available here. (Accessed: 27 November 2011).
¤ ‘MSL Atlas Launch MECO + Separation NASATV HD mars 11/26/2011’ (2011). JPL. [Online]. Available here. (Accessed: 27 November 2011).
¤ Vasavada, A (2011). ‘Mars Rover Power’ JPLnews. [Online]. Available here. (Accessed: 16 November 2011).
¤ ‘JPL Rovers’ (2011). JPL. [Online]. Available here. (Accessed: 06 November 2011).
¤ ‘Animation improvements’ (2011). Aniden. [Online]. Available here. (Accessed: 06 November 2011).

Images

¤ All images edited by ren@rt. Source: JPL, NASA.

ATLANTIS – FAREWELL TO THE SPACE SHUTTLE

Space Shuttle Atlantis launched from Kennedy Space Centre on 8th July 2011. Despite light rain and cloudy skies, meteorological conditions were safe for a successful departure into orbit.

Space Shuttle Atlantis is the last orbital vehicle of a fleet of five spacecraft that form part of NASA’s 30-year Space Shuttle Programme. The other orbiters are: Columbia, Challenger, Discovery and Endeavour. The first two lost in fatal accidents that highlight the dangers that the programme has to face at every stage of its performance.

Mission 135 marks the end of one of the biggest accomplishments of humankind; the construction of the International Space Station (ISS), an artificial environment that supports human life outside Earth’s atmosphere.

The end of the building phase is the beginning of the productive period of the ISS, a space post dedicated entirely to scientific research. A multinational collaborative effort in space exploration fuelled by the recognition that the future of our species may potentially rely on finding habitable solutions outside our planet.

Since the 1980s there has been an explosion of technologies that used the services of the Space Shuttle Programme, from transporting provisions to the ISS to delivery and retrieval of equipment and satellites from orbital altitudes.

On this mission, Commander Chris Ferguson and Pilot Doug Hurley teamed-up with Mission Specialists Sandy Magnus and Rex Walheim in a 12-day excursion to the ISS. They will have the following objectives:

• Transport of “Raffaello,” the multi-purpose logistics module (MPLM), filled with 9 tonnes of supplies, experiments and spare parts for the ISS. A combined effort of NASA (National Aeronautics and Space Administration) and ASI (Agenzia Spaziale Italiana). This unit acts as a “moving van” to ferry cargo back and forth to the station. The crew will bring back debris and material no longer required at the station.
• Delivery of the Advanced Recycle Filter Tank Assembly (ARFTA), a titanium tank containing a bellows made of Hastelloy, the only materials known to withstand the corrosive effects of concentrated pre-treated urine/brine. Its function is to collect residue left over from extracting water from astronaut urine, a part of the station’s Water Recovery System (WRS), which produces purified potable water from crew urine.
• Delivery of the Robotic Refuelling Mission (RRM), an experiment to evaluate procedures of robotically refuelling satellites in space, even those not designed to be serviced. This mission as developed between NASA and the Canadian Space Agency (CSA). This will lay the foundation for future robotic servicing missions.
• Transport of the Lightweight Multi-Purpose Carrier (LMC) that will be used to return a failed Ammonia Pump from the ISS
• Carry the cryogenic transportation freezer GLACIER to carry experiment samples.
• Transport many experiments including a materials experiment to be installed outside the station.

The crew of STS-135 will support a spacewalk carried out by members currently stationed at the ISS.

Flight Engineers Michael Fossum and Ron Garan will perform one spacewalk on the fifth day of the mission. On this occasion they will test a new procedure tried out by the previous mission in order to cut down the use of oxygen in preparation for the spacewalk. Instead of spending the night before the procedure in the low pressure capsule “Quest,” they will breathe pure oxygen for an hour while the pressure is lowered. Then they will put on their spacesuits and perform light exercise to increase their metabolic rate and purge nitrogen from their bloodstream.

During the 6.5 hour spacewalk the astronauts will retrieve the failed pump module, install the Robotic Refuelling Mission experiment and deploy materials for another experiment.

In addition to their activities, the mission is taking many experiments to the station and also bringing some back to Earth.

Update on the mission

The routine inspection of the heat shield using Canadarm2 on board the Shuttle revealed no visible damage to the tiles during launch. Similar results were found in the analysis of photos taken with the 3 ISS cameras (400, 800 and 1000mm lens cameras) during the Shuttle’s roll-over or “rendezvous pitch” manoeuvre.

After a flawless docking to the ISS, the 12th of Shuttle Atlantis, the crew of astronauts were welcomed by their colleagues at the station.

The team on the ground was watching a piece of debris travelling in an orbit close to that of the space station. They feared a “conjunction” or moment of maximum proximity to the station to happen on the day of the spacewalk. Interestingly, the docking of the Shuttle to the station resulted in a change in trajectory sufficient to avoid that of the approaching debris.

The spacewalk went well with almost all tasks completed successfully. Thanks to the live transmission, courtesy of NASA-TV, the world was able to witness the complexity and exhausting job that the astronauts have to do in those continuous 6.5hr in space. After almost 250 spacewalks in history, the delicate procedure now runs smoothly with minimal problems.

The morning after the spacewalk, the astronauts woke-up to the tune of the song “Rocket man” followed by a short message from its author Sir Elton John, who acknowledged the 3 decades of success of the Shuttle Space Programme. The crew also had the chance to show off their floating skills during interviews with the media, interested in the progress of the last mission of the programme.

Meantime on Earth, in the Atlantic coast at Cape Canaveral in Florida; a convoy of vessels conducted the final recovery of Solid Fuel Rocket Boosters in the programme, the only re-usable parts besides the shuttle. The recovery convoy was led by a boat marking the occasion blowing its sirens and shooting water towards the sky as they travelled to port for the last time.

The last duties of Mission STS-135 revolved around transporting cargo to and from the station, ensuring that the ISS is sufficiently supplied for up to one year.

Seven days after docking to the space station the astronauts on board ISS got together for a farewell ceremony before preparation for undocking.

Commander Chris Ferguson presented the crew of Expedition-28 living at ISS a signed model of the Shuttle that will stay next to the entry hatch, as a monument to the accomplishments of the Space Shuttle Programme.

The crew also left an American Flag that flew on the first Space Shuttle Mission, STS-1, which will be placed on top of the hatch that leads to Atlantis. The flag will be returned to Earth by the next American astronaut launching on a new generation US vehicle, marking the continuation of space exploration beyond the age of the Space Shuttle Programme.

The crew of Atlantis carried along their mission a symbolic national flag from the Miami Dade Police Department. It will be returned upon landing with the added value of having been to almost as far as humans can go.

On Tuesday 19th July, undocking proceeded without a hitch, followed by a flight around the station. This time the station rotated 90 degrees to allow viewing areas that are usually missed by this manoeuvre.

Two separation burns moved the Shuttle away from the ISS and closer to our planet. The crew then made another stop to inspect the heat shield for damage that might have occurred while docked to the station.

The next day, before preparations for re-entry burn, Atlantis made its 180th deployment: the mini-satellite PICO, its purpose is to take the last pictures of the Shuttle as it re-enters our atmosphere. This satellite weights 4kg and measures 12x12x20cm; it is covered with solar cells to test a new solar cell technology. During flight it was stored in a small canister inside the cargo bay, under Canadarm-1 and the KU-Band communications antenna (golden structure in the pictures), which helped downlink the excellent television images to the control room and NASA-TV.

On the same date, 20th July in 1969, Neil Armstrong walked on the moon. Celebrating this occasion the astronauts had their last interview with the media and did a great job as ambassadors of the space programme. Their message was: “Take a look back at the landing of Atlantis and make a memory because you will never see the landing of a Space Shuttle again.”

Landing

Early morning on Thursday, 21st July 2011, Atlantis proceeded with the final de-orbit burn to slow down the spacecraft, which is done with the spacecraft moving backwards. Then it turned around and lifted the nose to expose the thermal shield to the zone of most friction as it entered the atmosphere. At that point, the heat shield was put to test when temperatures around the Shuttle -reached 13,800 degrees Celsius (25000 F).

In its descent, the spacecraft slowed down from 24 to 14 times the speed of sound as it travelled across the Gulf of Mexico towards Cape Canaveral. It flew by over Naples, Florida at 6 times the speed of sound; 5 minutes later, Atlantis went sub-sonic and everyone around could hear the twin sonic booms.

Pilot Doug Hurley took over control of the aircraft until touch down, culminating the mission at the official elapsed time of 12 days 18 hours 28min and 14 seconds.

Space Shuttle Atlantis

The Space Shuttle Atlantis was the fourth Orbiter Vehicle designed by the company Rockwell International in 1985. Since then it has served the programme in a large number of achievements and number first in the following:

• First to deploy a probe to another planet (Magellan towards Venus, also Galileo to the outer planets including Jupiter)
• First to dock to the space station Russian MIR
• First shuttle with glass cockpit

Some of the highlight of its many years of service include:

• 1985, 3 October: First flight carrying Mission STS-51j that deployed two DSCS-III (Defence Satellite Communications System) satellites into stationary orbit
• 1985 second mission STS-61b: Deployed 3 communications satellites: MORELOS-B, AUSSAT-2 and SATCOM KU-2
• 1986 Challenger accident: Grounds the Shuttle fleet
• 1988, 2 December: Deployed the Lacrosse 1 satellite, for the US National Reconnaissance Office (NRO) and the Central Intelligence Agency (CIA)
• 1989, 2 missions: The first one to deploy the Magellan spacecraft to capture images of Venus; and Galileo released towards Jupiter
• 1990, 2 missions to deliver satellites for the Department of Defence: The Misty reconnaissance satellite and a secret Magnum ELINT (ELectronic INTtelligence) gathering satellite.
• 1995, 29 June, the first Mission to dock on the Russian MIR, starting the cooperation of the two former enemy countries in the project SPACELAB/MIR
• 2000 start of the ISS assembly missions with the first component, followed by missions dedicated to this purpose.
• 2009, 11 May, Historic Hubble Space Telescope final Servicing Mission replacing and adjusting the optics to maximize its performance.

"Launching Our Dreams: A Shuttle Retrospective" and "STS-135 Mission Overview"

Atlantis Art

Last chance to see Atlantis from your backyard !

NASA offers a service to help you track the progress of the ISS and other satellites in the night sky. All you need is a pair of binoculars and ideally somewhere solid to lean on. The service is “Sighting Opportunities” and can be found here.

Find your country and city using the Search field and a table will tell you when, and where to look for the spacecraft in the sky.

References

¤ ‘History of the Space Shuttle’ (2011). NASA. [Online]. Available here. (Accessed: 08 July 2011).
¤ ‘Mission STS-135’ (2011). NASA. [Online]. Available here. (Accessed: 08 July 2011).
¤ ‘NASA HD-TV’ (2011). NASA-TV. [Online]. Available here. (Accessed: 18 July 2011).
¤ ‘Sighting Opportunities’ (2011). NASA. [Online]. Available here. (Accessed: 19 July 2011).
¤ ‘Space Shuttle Atlantis’ (2011). Wikipedia. [Online]. Available here. (Accessed: 18 July 2011).

Images

¤ All images edited by ren@rt. Source: NASA.