Mars Exploration Rovers

NASA's twin robot geologists, the Mars Exploration Rovers, launched toward Mars on June 10 and July 7, 2003, in search of answers about the history of water on Mars. They landed on Mars January 3 and January 24 PST, 2004 (January 4 and January 25 UTC, 2004).
The Mars Exploration Rover mission is part of NASA's Mars Exploration Program, a long-term effort of robotic exploration of the red planet.
Primary among the mission's scientific goals is to search for and characterize a wide range of rocks and soils that hold clues to past water activity on Mars. The spacecraft are targeted to sites on opposite sides of Mars that appear to have been affected by liquid water in the past. The landing sites are at Gusev Crater, a possible former lake in a giant impact crater, and Meridiani Planum, where mineral deposits (hematite) suggest Mars had a wet past.
After the airbag-protected landing craft settled onto the surface and opened, the rovers rolled out to take panoramic images. These images give scientists the information they need to select promising geological targets that tell part of the story of water in Mars' past. Then, the rovers drive to those locations to perform on-site scientific investigations.
These are the primary science instruments carried by the rovers:
Panoramic Camera (Pancam): for determining the mineralogy, texture, and structure of the local terrain.
Miniature Thermal Emission Spectrometer (Mini-TES): for identifying promising rocks and soils for closer examination and for determining the processes that formed Martian rocks. The instrument is designed to look skyward to provide temperature profiles of the Martian atmosphere.
Mössbauer Spectrometer (MB): for close-up investigations of the mineralogy of iron-bearing rocks and soils.
Alpha Particle X-Ray Spectrometer (APXS): for close-up analysis of the abundances of elements that make up rocks and soils.
Magnets: for collecting magnetic dust particles. The Mössbauer Spectrometer and the Alpha Particle X-ray Spectrometer are designed to analyze the particles collected and help determine the ratio of magnetic particles to non-magnetic particles. They can also analyze the composition of magnetic minerals in airborne dust and rocks that have been ground by the Rock Abrasion Tool.
Microscopic Imager (MI): for obtaining close-up, high-resolution images of rocks and soils.
Rock Abrasion Tool (RAT): for removing dusty and weathered rock surfaces and exposing fresh material for examination by instruments onboard.
Before landing, the goal for each rover was to drive up to 40 meters (about 44 yards) in a single day, for a total of up to one 1 kilometer (about three-quarters of a mile). Both goals have been far exceeded!
Moving from place to place, the rovers perform on-site geological investigations. Each rover is sort of the mechanical equivalent of a geologist walking the surface of Mars. The mast-mounted cameras are mounted 1.5 meters(5 feet) high and provide 360-degree, stereoscopic, humanlike views of the terrain. The robotic arm is capable of movement in much the same way as a human arm with an elbow and wrist, and can place instruments directly up against rock and soil targets of interest. In the mechanical "fist" of the arm is a microscopic camera that serves the same purpose as a geologist's handheld magnifying lens. The Rock Abrasion Tool serves the purpose of a geologist's rock hammer to expose the insides of rocks.

-marsrover.nasa.gov/overview/

STS-51-L...The Tragedy of Challenger

The first shuttle liftoff scheduled from Pad B. Launch was set for 3:43 p.m. EST, Jan. 22, slipped to Jan. 23, then Jan. 24, due to delays in mission 61-C. Launch was reset for Jan. 25 because of bad weather at the transoceanic abort landing (TAL) site in Dakar, Senegal. To utilize Casablanca (not equipped for night landings) as alternate TAL site, T-zero was moved to a morning liftoff time. The launch postponed another day when launch processing was unable to meet the new morning liftoff time. Prediction of unacceptable weather at KSC led to the launch being rescheduled for 9:37 a.m. EST, Jan. 27. The launch was delayed 24 hours again when the ground servicing equipment hatch closing fixture could not be removed from the orbiter hatch. The fixture was sawed off and an attaching bolt drilled out before closeout was completed. During the delay, cross winds exceeded return-to-launch-site limits at KSC's Shuttle Landing Facility. The launch Jan. 28 was delayed two hours when a hardware interface module in the launch processing system, which monitors the fire detection system, failed during liquid hydrogen tanking procedures.Just after liftoff at .678 seconds into the flight, photographic data shows a strong puff of gray smoke was spurting from the vicinity of the aft field joint on the right solid rocket booster. Computer graphic analysis of the film from the pad cameras indicated the initial smoke came from the 270 to 310-degree sector of the circumference of the aft field joint of the right solid rocket booster. This area of the solid booster faces the external tank. The vaporized material streaming from the joint indicated there was not a complete sealing action within the joint.Eight more distinctive puffs of increasingly blacker smoke were recorded between .836 and 2.500 seconds. The smoke appeared to puff upwards from the joint. While each smoke puff was being left behind by the upward flight of the shuttle, the next fresh puff could be seen near the level of the joint. The multiple smoke puffs in this sequence occurred at about four times per second, approximating the frequency of the structural load dynamics and resultant joint flexing. As the shuttle increased its upward velocity, it flew past the emerging and expanding smoke puffs. The last smoke was seen above the field joint at 2.733 seconds.The black color and dense composition of the smoke puffs suggest that the grease, joint insulation and rubber O-rings in the joint seal were being burned and eroded by the hot propellant gases.At approximately 37 seconds, Challenger encountered the first of several high-altitude wind shear conditions, which lasted until about 64 seconds. The wind shear created forces on the vehicle with relatively large fluctuations. These were immediately sensed and countered by the guidance, navigation and control system. The steering system (thrust vector control) of the solid rocket booster responded to all commands and wind shear effects. The wind shear caused the steering system to be more active than on any previous flight.Both the shuttle main engines and the solid rockets operated at reduced thrust approaching and passing through the area of maximum dynamic pressure of 720 pounds per square foot. The main engines had been throttled up to 104 percent thrust and the solid rocket boosters were increasing their thrust when the first flickering flame appeared on the right solid rocket booster in the area of the aft field joint. This first very small flame was detected on image enhanced film at 58.788 seconds into the flight. It appeared to originate at about 305 degrees around the booster circumference at or near the aft field joint.One film frame later from the same camera, the flame was visible without image enhancement. It grew into a continuous, well-defined plume at 59.262 seconds. At about the same time (60 seconds), telemetry showed a pressure differential between the chamber pressures in the right and left boosters. The right booster chamber pressure was lower, confirming the growing leak in the area of the field joint.As the flame plume increased in size, it was deflected rearward by the aerodynamic slipstream and circumferentially by the protruding structure of the upper ring attaching the booster to the external tank. These deflections directed the flame plume onto the surface of the external tank. This sequence of flame spreading is confirmed by analysis of the recovered wreckage. The growing flame also impinged on the strut attaching the solid rocket booster to the external tank.The first visual indication that swirling flame from the right solid rocket booster breached the external tank was at 64.660 seconds when there was an abrupt change in the shape and color of the plume. This indicated that it was mixing with leaking hydrogen from the external tank. Telemetered changes in the hydrogen tank pressurization confirmed the leak. Within 45 milliseconds of the breach of the external tank, a bright sustained glow developed on the black-tiled underside of the Challenger between it and the external tank.Beginning at about 72 seconds, a series of events occurred extremely rapidly that terminated the flight. Telemetered data indicated a wide variety of flight system actions that support the visual evidence of the photos as the shuttle struggled futilely against the forces that were destroying it.At about 72.20 seconds the lower strut linking the solid rocket booster and the external tank was severed or pulled away from the weakened hydrogen tank permitting the right solid rocket booster to rotate around the upper attachment strut. This rotation is indicated by divergent yaw and pitch rates between the left and right solid rocket boosters.At 73.124 seconds, a circumferential white vapor pattern was observed blooming from the side of the external tank bottom dome. This was the beginning of the structural failure of hydrogen tank that culminated in the entire aft dome dropping away. This released massive amounts of liquid hydrogen from the tank and created a sudden forward thrust of about 2.8 million pounds, pushing the hydrogen tank upward into the intertank structure. At about the same time, the rotating right solid rocket booster impacted the intertank structure and the lower part of the liquid oxygen tank. These structures failed at 73.137 seconds as evidenced by the white vapors appearing in the intertank region.Within milliseconds there was massive, almost explosive, burning of the hydrogen streaming from the failed tank bottom and liquid oxygen breach in the area of the intertank.At this point in its trajectory, while traveling at a Mach number of 1.92 at an altitude of 46,000 feet, Challenger was totally enveloped in the explosive burn. The Challenger's reaction control system ruptured and a hypergolic burn of its propellants occurred as it exited the oxygen-hydrogen flames. The reddish brown colors of the hypergolic fuel burn are visible on the edge of the main fireball. The orbiter, under severe aerodynamic loads, broke into several large sections which emerged from the fireball. Separate sections that can be identified on film include the main engine/tail section with the engines still burning, one wing of the orbiter, and the forward fuselage trailing a mass of umbilical lines pulled loose from the payload bay.The explosion 73 seconds after liftoff claimed crew and vehicle. The cause of explosion was determined to be an o-ring failure in the right solid rocket booster. Cold weather was determined to be a contributing factor.

http://www.nasa.gov/mission_pages/shuttle/shuttlemissions/archives/sts-51L.html
Creadits-NASA.gov & Nasa News Central

NASA'S Orion Spacecraft to Land in Oklahoma, Texas and Alabama

A test version of NASA's Orion spacecraft soon will make a cross-country journey, giving residents in three states the chance to see a full scale test version of the vehicle that will take humans into deep space. The crew module will make stops during a trip from the White Sands Missile Range in New Mexico to the Kennedy Space Center in Florida. The planned stops include Jan. 24-25 at Science Museum Oklahoma in Oklahoma City; Jan. 27-29 at Victory Park and the American Airlines Center in Dallas; and, Feb. 1-2 at the U.S. Space and Rocket Center in Huntsville, Ala. Engineers, program officials, astronauts and NASA spokespeople will be available to speak with the media and the public. The full-scale test vehicle was used by ground crews in advance of the launch abort system flight test that took place in New Mexico in 2010. Orion will serve as the vehicle that takes astronauts beyond low-Earth orbit, and the first orbital flight test is scheduled for 2014.
NASA.gov

Launch of the first private spacecraft to the ISS delayed

SpaceX showcased the company's flown Dragon space capsule at an event jointly hosted with Tesla Motors in Washington, D.C. on Feb. 10, 2011.
CREDIT: SPACE.com/Denise Chow
The launch of the first privately built spacecraft to the International Space Station has been delayed until late March at the earliest, the company building the spaceship revealed today (Jan. 20).

The California-based company Space Exploration Technologies (SpaceX) originally planned to launch its unmanned Dragon space capsule on a maiden flight to the space station on Feb. 7, but the company  postponed the orbital test flight to allow time for more work on the spacecraft.

Now, SpaceX officials said the flight will likely occur sometime in the spring, though NASA and SpaceX have not yet to set official launch target.

"It won't be earlier than late March," SpaceX spokesperson Kirstin Grantham told SPACE.com.

In the meantime, the company will resume preparations for the upcoming flight, which aims to test the Dragon capsule's ability to rendezvous and dock with the orbiting complex.

SpaceX's Dragon capsule will launch atop the company's Falcon 9 rocket on a mission to demonstrate the vehicle's ability to carry cargo to the space station. As the spacecraft approaches, members of the space station crew will use a robotic arm to grab the vehicle and attach it to the station.

If it is successful, SpaceX will be the first commercial company to rendezvous and dock to the orbiting outpost.

This will be SpaceX's second flight under NASA's Commercial Orbital Transportation Services (COTS) program. Dragon launched on its first test flight in December 2010, completed two orbits of Earth, and then splashed down in the Pacific Ocean. The mission marked the first time a commercial company launched and returned a capsule from space.

NASA's COTS program is designed to nurture the development of new private spaceships to deliver vital supplies to the space station. Under the agency's current agreement with SpaceX, the California-based company will receive up to $396 million for the successful completion of the milestones outlined in their Space Act Agreement.

SPACE.com & Nasa news central

Voyager mission report

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  PASADENA, Calif. -- In order to reduce power consumption, mission managers have turned off a heater on part of NASA's Voyager 1 spacecraft, dropping the temperature of its ultraviolet spectrometer instrument more than 23 degrees Celsius (41 degrees Fahrenheit). It is now operating at a temperature below minus 79 degrees Celsius (minus 110 degrees Fahrenheit), the coldest temperature that the instrument has ever endured. This heater shut-off is a step in the careful management of the diminishing electrical power so that the Voyager spacecraft can continue to collect and transmit data through 2025.

  At the moment, the spectrometer continues to collect and return data. It was originally designed to operate at temperatures as low as minus 35 degrees Celsius (minus 31 degrees Fahrenheit), but it has continued to operate in ever chillier temperatures as heaters around it have been turned off over the last 17 years. It was not known if the spectrometer would continue working, but since 2005, it has been operating at minus 56 degrees Celsius (minus 69 degrees Fahrenheit.) So engineers are encouraged that the instrument has continued to operate, even after the nearby heater was turned off in December. (The spectrometer is likely operating at a temperature somewhat lower than minus 79 degrees Celsius, or minus 110 degrees Fahrenheit, but the temperature detector does not go any lower.)

  Scientists and mission managers will continue to monitor the spectrometer's performance. It was very active during Voyager 1's encounters with Jupiter and Saturn, and since then an international team led by scientists in France has been analyzing the spectrometer's data.

  This latest heater shut-off was actually part of the nearby infrared spectrometer, which itself has not been operational on Voyager 1 since 1998.

  The Voyager spacecraft were built by NASA's Jet Propulsion Laboratory in Pasadena, Calif., which continues to operate both. JPL is a division of the California Institute of Technology in Pasadena. The Voyager missions are a part of the NASA Heliophysics System Observatory, sponsored by the Heliophysics Division of the Science Mission Directorate in Washington. For more information about the Voyager spacecraft, visit:http://www.nasa.gov/voyagerandhttp://voyager.jpl.nasa.gov.

  NASA.gov; Jacob

Space Shuttle Atlantis's new home

With space shuttle Atlantis' 25-year spaceflight career now in the history books, its next mission -- to inform and inspire generations of visitors to the Kennedy Space Center Visitor Complex in Florida -- is one step closer to reality. A groundbreaking ceremony Jan. 18 officially launched construction of a new 65,000-square-foot exhibit at the complex's Space Shuttle Plaza, where NASA's fourth space-rated orbiter will be the main attraction.
"It is an honor to create the home for space shuttle Atlantis and to work with NASA to tell its story to the world," said Jeremy Jacobs, chairman and chief executive officer of Delaware North Companies, which operates the visitor complex for NASA.
Participating in the event were Jacobs; Janet Petro, Kennedy Space Center deputy director; Chris Ferguson, who commanded Atlantis on its final mission, STS-135; Bill Moore, chief operating officer of the Kennedy Space Center Visitor Complex; and Florida Lt. Governor Jennifer Carroll. Wearing hard hats and gripping shovels, they made the ceremonial first turn of the soil at the construction site.
From October 1985 to July 2011, Atlantis helped carry the nation's astronauts and payloads on journeys into low Earth orbit. The spacecraft was the first to dock with the Russian space station Mir and aided in the construction of the International Space Station. From Atlantis' payload bay, NASA deployed the Magellan and Galileo planetary probes, the Compton Gamma Ray Observatory and other satellites. Atlantis also was the last shuttle to fly a servicing mission to NASA's Hubble Space Telescope.
It's a legacy NASA is eager to share through the new exhibit, which is expected to open in 2013.
"It's very fortunate we can celebrate this milestone, fortunate we had the foresight and the resources to preserve Atlantis to serve as a reminder of the limitless potential of the citizens of the United States of America, and inspire those who will come after us," Ferguson said.
The vehicle will be displayed as if in flight with its payload bay doors open, offering a view of its 60-foot-long cargo area. Additionally, a variety of simulators and interactive elements will offer visitors the chance to experience the challenge of grappling a satellite or move through a model of the International Space Station.
"This is not just a story about the hardware," said Moore. "This is really a true story of hardworking people who worked together -- thousands of people -- to do amazing things."
NASA Administrator Charles Bolden announced on April 12, 2011, that Atlantis would stay at the Florida spaceport following its retirement. The welcomed news came on the 30-year anniversary of the first space shuttle flight.
Atlantis flew nearly 126 million miles during a total of 307 days in space. It returned to Earth for good on July 21, 2011, its main landing gear kicking up dust for the last time on Kennedy's shuttle runway with a predawn touchdown at 5:57 a.m. EDT.
"This coming Saturday does mark six months since the final landing of Atlantis out here, about three miles behind me," said Ferguson. "With that final landing, the shuttle program came to a conclusion after 30 years of discovery and exploration. At times we had to lick our wounds, at times there were joyous moments, but by the grace of God we concluded the program just the way we wanted to, very safely."
After undergoing standard post-mission processing, Atlantis entered into its longer "transition and retirement" phase. Each vehicle's trio of main engines will be replaced with mock-ups; the real engines are being saved for use on a new heavy-lift rocket, the Space Launch System. The orbital maneuvering system (OMS) pods and forward reaction control system, which used toxic propellants, will be cleaned and deserviced at White Sands Test Facility in Las Cruces, N.M. Ultimately, the engines in the OMS pods will be replaced with replicas.
Although Atlantis will remain close by, the other spacecraft in the shuttle fleet will go to new exhibits outside of Florida. Shuttle Discovery is destined for the Smithsonian's National Air and Space Museum Steven F. Udvar-Hazy Center in Chantilly, Va., and Endeavour will be displayed at the California Science Center in Los Angeles. Enterprise, used in approach and landing tests at the advent of the Space Shuttle Program, will move to New York‘s Intrepid Sea, Air and Space Museum.
"For 30 years, the orbiters have been a part of our family. We've cared for them, we've protected them, and we've watched them soar. We've marveled at the similarities between them, and the differences that only 'family' could identify," said Janet Petro, deputy director of Kennedy Space Center. "Atlantis' new home is beautifully designed to showcase her as the true engineering marvel that she is."
NASA.gov & Jacob Jancsura

Photographing the International Space Station from Your Own Backyard

Multiple images of the International Space Station flying over the Houston area have been combined into one composite image to show the progress of the station as it crossed the face of the moon in the early evening of Jan. 4. Photo credit: NASA
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Photographing the International Space Station seems like something that could be done only from space, but taking a picture from your own backyard actually is easier than you might think.

If you have the right equipment, capturing your own photo of the space station from your hometown can be almost as easy as tracking it, and definitely more satisfying. NASA photographer Lauren Harnett, who took these photos, explained her technique for photographing the station with the moon as the background. But you can choose just about any landmark that is special to you to put in the foreground, as long as you’re careful to ensure the lighting conditions are right.

NASA invites you to share your photos of the space station and tell us the story about how and when you took them. On Facebook, tag the International Space Station page: http://www.facebook.com/#!/ISS in your photo. On Twitter, include #ISS with your photo. We may even choose a few to post on the NASA website or repost on our Facebook and Twitter accounts.

Camera Equipment Needed (This list represents what was used to take these photos; you can substitute your favorite gear):

The International Space Station can be seen as a small object in upper left of this image of the moon in the early evening Jan. 4 in the skies over the Houston area flying at an altitude of 390.8 kilometers (242.8 miles). Photo credit: NASA
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• Digital Single-Lens Reflex (DSLR) camera
• 600 mm lens (or the largest you have)
• 2X telephoto lens converter (amplifies lens)
• Trigger cable (minimizes camera shake)
• Tripod (heavy duty works best)
• Sandbag (keeps tripod stable)

Steps for Photographing the Space Station with the Moon:

First, determine when the space station is flying over your area and decide where to set up your equipment to take the photos. It is helpful to know from which direction the station is coming. Sightings information and exact dates and times are available on NASA’s SkyWatch website.

Allow plenty of time for set up at your chosen location, as it may take some time to get the tripod perfectly adjusted.

Make sure you check where the moon is and that it is in the phase (full, crescent, etc.) you want. Set up the tripod and camera pointing toward the moon. Adjusting the tripod may be tricky as tripod heads are not designed to tilt back to extreme angles for overhead shots. You may need to extend the two back legs of the tripod while keeping the front leg shorter to achieve the desired angle. Use the sandbag on the front leg to help balance the tripod.

Find the moon in the camera viewfinder, adjusting the tripod as needed. Harnett said, “Clouds can make it tricky. It can be a cat and mouse game finding the moon.”


The International Space Station can be seen as a small object in lower right of this image of the moon in the early evening Jan. 4 in the skies over the Houston area flying at an altitude of 390.8 kilometers (242.8 miles). Photo credit: NASA
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Harnett set her camera’s shutter speed to 1/1600 of a second, aperture at f/8 and ISO to 2500. You may need to adjust your settings to let in more or less light depending on the size and brightness of the moon or your foreground object, but this is a good starting-point.

Use the High Continuous Burst setting to capture the most images per second. Setting the camera to save the photos in raw image format is best. Be sure to use the manual focus.

It is a good idea to take a few test shots to ensure everything is set as you want. A few minutes before the station is expected to fly over, check the viewfinder again to ensure the moon is still in the shot, as it also is moving across the sky.

The station will be easy to identify when it comes into view as it is extremely bright and moves rather quickly. You can see it with the naked eye.

Once the space station is in the field of view (or close to it), press and hold down the cabled trigger release until the station leaves your field of view. Then check the photos on your camera to see if they turned out the way you wanted.

You are now ready to experiment with taking your own photos of the space station. If they don’t turn out the way you want the first time, you can always try again. Then again, your photos may turn out so great you’ll want to take them every chance you get!

Lori Keith
NASA’s Johnson Space Center

Reposted by James

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NASA moves space shuttle engines

The relocation of the RS-25D space shuttle main engine inventory from Kennedy Space Center's Engine Shop in Cape Canaveral, Fla., is underway. The RS-25D flight engines, repurposed for NASA's Space Launch System, are being moved to NASA's Stennis Space Center in south Mississippi.
The Space Launch System (SLS) is a new heavy-lift launch vehicle that will expand human presence beyond low-Earth orbit and enable new missions of exploration across the solar system. The Marshall Space Flight Center in Huntsville, Ala., is leading the design and development of the SLS for NASA, including the engine testing program. SLS will carry the Orion spacecraft, its crew, cargo, equipment and science experiments to destinations in deep space.
"The relocation of RS-25D engine assets represents a significant cost savings to the SLS Program by consolidating SLS engine assembly and test operations at a single facility," said William Gerstenmaier, NASA's Associate Administrator for Human Exploration and Operations Mission Directorate.
The RS-25Ds -- to be used for the SLS core stage -- will be stored at Stennis until testing begins at a future date. Testing is already under way on the J-2X engine, which is planned for use in the SLS upper stage. Using the same fuel system -- liquid hydrogen and liquid oxygen -- for both core and upper stages reduces costs by leveraging the existing knowledge base, skills, infrastructure and personnel.
"This enables the sharing of personnel, resources and practices across all engine projects, allows flexibility and responsiveness to the SLS program, and it is more affordable," said Johnny Heflin, RS-25D core stage engine lead in the SLS Liquid Engines Office at Marshall. "It also frees up the space, allowing Kennedy to move forward relative to commercial customers."
The 15 RS-25D engines at Kennedy are being transported on the 700-mile journey using existing transportation and processing procedures that were used to move engines between Kennedy and Stennis during the Space Shuttle Program. They will be relocated one at time by truck.
Built by Pratt & Whitney Rocketdyne of Canoga Park, Calif. the RS-25D engine powered NASA's space shuttle program with 100 percent mission success.
For more information about SLS, visit:
http://www.nasa.gov/sls

Latest Hubble news

Hubble Solves Mystery on Source of Supernova in Nearby Galaxy
 

Using NASA's Hubble Space Telescope, astronomers have solved a longstanding mystery on the type of star, or so-called progenitor, which caused a supernova seen in a nearby galaxy. The finding yields new observational data for pinpointing one of several scenarios that trigger such outbursts.
This image of Type Ia Supernova Remnant 0509-67.5 was made by combining data from two of NASA's Great Observatories. The result shows soft green and blue hues of heated material from the X-ray data surrounded by the glowing pink optical shell, which shows the ambient gas being shocked by the expanding blast wave from the supernova. Credit: NASA, ESA, and B. Schaefer and A. Pagnotta (Louisiana State University, Baton Rouge); Image Credit: NASA, ESA, CXC, SAO, the Hubble Heritage Team (STScI/AURA), J. Hughes (Rutgers University)
> Larger image
Based on previous observations from ground-based telescopes, astronomers knew the supernova class, called a Type Ia, created a remnant named SNR 0509-67.5, which lies 170,000 light-years away in the Large Magellanic Cloud galaxy.
Theoretically, this kind of supernova explosion is caused by a star spilling material onto a white dwarf companion, the compact remnant of a normal star, until it sets off one of the most powerful explosions in the universe.
Astronomers failed to find any remnant of the companion star, however, and concluded that the common scenario did not apply in this case, although it is still a viable theory for other Type Ia supernovae.
"We know Hubble has the sensitivity necessary to detect the faintest white dwarf remnants that could have caused such explosions," said lead investigator Bradley Schaefer of Louisiana State University (LSU) in Baton Rouge. "The logic here is the same as the famous quote from Sherlock Holmes: 'when you have eliminated the impossible, whatever remains, however improbable, must be the truth.'"
The cause of SNR 0509-67.5 can be explained best by two tightly orbiting white dwarf stars spiraling closer and closer until they collided and exploded.
For four decades, the search for Type Ia supernovae progenitors has been a key question in astrophysics. The problem has taken on special importance during the last decade with Type Ia supernovae being the premier tools for measuring the accelerating universe.
Type Ia supernovae release tremendous energy, in which the light produced is often brighter than an entire galaxy of stars. The problem has been to identify the type of star system that pushes the white dwarf's mass over the edge and triggers this type of explosion. Many possibilities have been suggested, but most require that a companion star near the exploding white dwarf be left behind after the explosion.
Therefore, a possible way to distinguish between the various progenitor models has been to look deep in the center of an old supernova remnant to search for the ex-companion star.
In 2010, Schaefer and Ashley Pagnotta of LSU were preparing a proposal to look for any faint ex-companion stars in the center of four supernova remnants in the Large Magellanic Cloud when they discovered the Hubble Space Telescope already had taken the desired image of one of their target remnants, SNR 0509-67.5, for the Hubble Heritage program, which collects images of especially photogenic astronomical targets.
In analyzing the central region, they found it to be completely empty of stars down to the limit of the faintest objects Hubble can detect in the photos. Schaefer suggests the best explanation left is the so-called "double degenerate model" in which two white dwarfs collide.
The results are being reported today at the meeting of the American Astronomical Society in Austin, Texas. A paper on the results will be published in the Jan. 12 issue of the journal Nature.
There are no recorded observations of the star exploding. However, researchers at the Space Telescope Science Institute in Baltimore, Md. have identified light from the supernova that was reflected off of interstellar dust, delaying its arrival at Earth by 400 years. This delay, called a light echo of the supernova explosion also allowed the astronomers to measure the spectral signature of the light from the explosion. By virtue of the color signature, astronomers were able to deduce it was a Type Ia supernova.
Because the remnant appears as a nice symmetric shell or bubble, the geometric center can be determined accurately. These properties make SNR 0509-67.5 an ideal target to search for ex-companions. The young age also means that any surviving stars have not moved far from the site of the explosion.
The team plans to look at other supernova remnants in the Large Magellenic Cloud to further test their observations.
The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI) conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington, D.C.
 
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James Webb Space Telescope

The James Webb Space Telescope marked a year of significant progress in 2011 as it continues to come together as NASA's next generation space telescope. The year brought forth a pathfinder backplane to support the large primary mirror structure, mirror cryotesting, creation of mirror support structures, several successful sunshield layer tests and the creation of an assembly station within NASA Goddard Space Flight Center's cleanroom. Achievements were also made in the areas of flight and communications software and the propulsion system.rThe first six flight ready James Webb Space Telescope's primary mirror segments are prepped to begin final cryogenic testing at NASA's Marshall Space Flight Center in Huntsville, Ala. Credit: NASA/Chris Gunn In December, manufacturing and testing of all flight mirrors was completed in a final test at the X-ray and Calibration Facility at Marshall Space Flight Center, Huntsville, Ala. During these tests mirror segments were chilled to temperatures similar to those Webb will see in space, around minus 400 degrees Fahrenheit.It was the culmination of work started in 2003. Heeding lessons learned from the Hubble Space Telescope, the program adopted the strategy of tackling the most difficult technical challenges first. That decision proved to be the right one. In June, all 18 flight primary mirror segments, plus the secondary, tertiary and fine steering mirrors, were polished and coated yielding exquisite surfaces that will enable Webb to image the most distant galaxies.Two of Webb’s supporting and pathfinder structures were also completed. To assemble the flight telescope on the ground, a 139,000 pound structure will install the flight mirrors using an overhead track system supporting a robotic arm. The huge platform has been completed and assembled in the ultra-clean room used for telescope assembly at Goddard.Also finished was the pathfinder backplane, a full-scale engineering model of the center section of the flight backplane. The backplane holds the mirror segments in place to form a single primary mirror. The full pathfinder element will consist of 12 of the 18 hexagonal cells (the center section of the primary mirror) of the telescope and contain a subset of two primary mirror segment assemblies, the secondary mirror, and the subsystem containing the tertiary and fine steering mirrors. It will demonstrate integration and test procedures that will be used on the flight telescope.Webb’s giant sunshield moved forward into a new testing phase last year, the final step before fabrication of the flight sunshield. Sunshield layer three became the first of five full-size flight-like layers stretched out in a fully simulated flight configuration. This enables engineers to make 3-D shape measurements that will tell them how the full-size sunshield layers will behave in space. Completing this test is a critical step in the sunshield’s development and gives the engineers confidence and experience needed to manufacture the five flight layers.An important sunshield deployment flight structure also completed fabrication in 2011. The space-qualified graphite composite tubes that will enable the sunshield to deploy in space have finished fabrication. The telescoping tube system was designed at Astro Aerospace, a business unit of Northrop Grumman.Capping the year’s achievements, Webb’s spacecraft also moved forward. The propulsion system’s 16 monopropellant rocket engine thrusters, which control momentum and station-keeping on orbit, were upgraded to accept higher heat loading from the sunshield. Propulsion engineers also completed building four flight secondary combustion augmented thrusters which maintain orbit after the launch vehicle finishes its burns. Engineers also verified the flight software responsible for ground commands and science data delivery.

-nasa.gov

Summary of the Space Shuttle Program

NASA's space shuttle fleet began setting records with its first launch on April 12, 1981 and continued to set high marks of achievement and endurance through 30 years of missions. Starting with Columbia and continuing with Challenger, Discovery, Atlantis and Endeavour, the spacecraft has carried people into orbit repeatedly, launched, recovered and repaired satellites, conducted cutting-edge research and built the largest structure in space, the International Space Station. The final space shuttle mission, STS-135, ended July 21, 2011 when Atlantis rolled to a stop at its home port, NASA's Kennedy Space Center in Florida.As humanity's first reusable spacecraft, the space shuttle pushed the bounds of discovery ever farther, requiring not only advanced technologies but the tremendous effort of a vast workforce. Thousands of civil servants and contractors throughout NASA's field centers and across the nation have demonstrated an unwavering commitment to mission success and the greater goal of space exploration.
-Nasa.com

final orion drop test

Orion, the next deep space exploration vehicle, will carry astronauts into space, provide emergency abort capability, sustain the crew during space travel, and ensure safe re-entry and landing. The testing, which began in July 2011, simulated different water landing scenarios and took into account different velocities, parachute deployments, entry angles, sea states and wind conditions that Orion could face when landing in the Pacific Ocean. The January 6 test represented worst case landing for an abort scenario in rough seas. The test impact conditions simulated all parachutes being deployed with a high impact pitch of 43 degrees. The capsule traveled approximately 47 mph (75.6 kph) before splashing into the basin and rolling over into the Stable 2 position. This type of landing scenario isn't likely to occur during actual vehicle operation, but is essential for the validation of analytical models. As was the case with Apollo, the Orion flight design will feature an onboard up-righting system.

Amy Johnson- NASA Langley Research Center

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