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Bubbly Little Star
Title Bubbly Little Star
Description In this processed Spitzer Space Telescope image, baby star HH 46/47 can be seen blowing two massive "bubbles." The star is 1,140 light-years away from Earth. The infant star can be seen as a white spot toward the center of the Spitzer image. The two bubbles are shown as hollow elliptical shells of bluish-green material extending from the star. Wisps of green in the image reveal warm molecular hydrogen gas, while the bluish tints are formed by starlight scattered by surrounding dust. These bubbles formed when powerful jets of gas, traveling at 200 to 300 kilometers per second, or about 120 to 190 miles per second, smashed into the cosmic cloud of gas and dust that surrounds HH 46/47. The red specks at the end of each bubble show the presence of hot sulfur and iron gas where the star's narrow jets are currently crashing head-on into the cosmic cloud's gas and dust material. Whenever astronomers observe a star, or snap a stellar portrait, through the lens of any telescope, they know that what they are seeing is slightly blurred. To clear up the blurring in Spitzer images, astronomers at the Jet Propulsion Laboratory developed an image processing technique for Spitzer called Hi-Res deconvolution. This process reduces blurring and makes the image sharper and cleaner, enabling astronomers to see the emissions around forming stars in greater detail. When scientists applied this image processing technique to the Spitzer image of HH 46/47, they were able to see winds from the star and jets of gas that are carving the celestial bubbles. This infrared image is a three-color composite, with data at 3.6 microns represented in blue, 4.5 and 5.8 microns shown in green, and 24 microns represented as red.
HH46/47
Title HH46/47
Description This image from NASA's Spitzer Space Telescope transforms a dark cloud into a silky translucent veil, revealing the molecular outflow from an otherwise hidden newborn star. Using near-infrared light, Spitzer pierces through the dark cloud to detect the embedded outflow in an object called HH 46/47. Herbig-Haro (HH) objects are bright, nebulous regions of gas and dust that are usually buried within dark clouds. They are formed when supersonic gas ejected from a forming protostar, or embryonic star, interacts with the surrounding interstellar medium. These young stars are often detected only in the infrared. The Spitzer image was obtained with the infrared array camera. Emission at 3.6 microns is shown as blue, emission from 4.5 and 5.8 microns has been combined as green, and 8.0 micron emission is depicted as red. HH 46/47 is a striking example of a low mass protostar ejecting a jet and creating a bipolar, or two-sided, outflow. The central protostar lies inside a dark cloud (known as a 'Bok globule') which is illuminated by the nearby Gum Nebula. Located at a distance of 1140 light-years and found in the constellation Vela, the protostar is hidden from view in the visible-light image (inset). With Spitzer, the star and its dazzling jets of molecular gas appear with clarity. The 8-micron channel of the infrared array camera is sensitive to emission from polycyclic aromatic hydrocarbons. These organic molecules, comprised of carbon and hydrogen, are excited by the surrounding radiation field and become luminescent, accounting for the reddish cloud. Note that the boundary layer of the 8-micron emission corresponds to the lower right edge of the dark cloud in the visible-light picture. Outflows are fascinating objects, since they characterize one of the most energetic phases of the formation of low-mass stars (like our Sun). The jets arising from these protostars can reach sizes of trillions of miles and velocities of hundreds of thousands miles per hour. Outflows are clear evidence of the presence of a process that creates supersonic beams of gas. This mechanism is tightly bound to the presence of circumstellar discs which surround the young stars. Such discs are likely to contain the materials from which planetary systems form. Our Sun probably underwent a similar process some 4.5 billion years ago. Hence the interest in understanding how quickly and efficiently this mass accretion and loss process takes place in protostars.
HH46/47
Title HH46/47
Description This image from NASA's Spitzer Space Telescope transforms a dark cloud into a silky translucent veil, revealing the molecular outflow from an otherwise hidden newborn star. Using near-infrared light, Spitzer pierces through the dark cloud to detect the embedded outflow in an object called HH 46/47. Herbig-Haro (HH) objects are bright, nebulous regions of gas and dust that are usually buried within dark clouds. They are formed when supersonic gas ejected from a forming protostar, or embryonic star, interacts with the surrounding interstellar medium. These young stars are often detected only in the infrared. The Spitzer image was obtained with the infrared array camera. Emission at 3.6 microns is shown as blue, emission from 4.5 and 5.8 microns has been combined as green, and 8.0 micron emission is depicted as red. HH 46/47 is a striking example of a low mass protostar ejecting a jet and creating a bipolar, or two-sided, outflow. The central protostar lies inside a dark cloud (known as a 'Bok globule') which is illuminated by the nearby Gum Nebula. Located at a distance of 1140 light-years and found in the constellation Vela, the protostar is hidden from view in the visible-light image (inset). With Spitzer, the star and its dazzling jets of molecular gas appear with clarity. The 8-micron channel of the infrared array camera is sensitive to emission from polycyclic aromatic hydrocarbons. These organic molecules, comprised of carbon and hydrogen, are excited by the surrounding radiation field and become luminescent, accounting for the reddish cloud. Note that the boundary layer of the 8-micron emission corresponds to the lower right edge of the dark cloud in the visible-light picture. Outflows are fascinating objects, since they characterize one of the most energetic phases of the formation of low-mass stars (like our Sun). The jets arising from these protostars can reach sizes of trillions of miles and velocities of hundreds of thousands miles per hour. Outflows are clear evidence of the presence of a process that creates supersonic beams of gas. This mechanism is tightly bound to the presence of circumstellar discs which surround the young stars. Such discs are likely to contain the materials from which planetary systems form. Our Sun probably underwent a similar process some 4.5 billion years ago. Hence the interest in understanding how quickly and efficiently this mass accretion and loss process takes place in protostars.
HH46/47
Title HH46/47
Description This image from NASA's Spitzer Space Telescope transforms a dark cloud into a silky translucent veil, revealing the molecular outflow from an otherwise hidden newborn star. Using near-infrared light, Spitzer pierces through the dark cloud to detect the embedded outflow in an object called HH 46/47. Herbig-Haro (HH) objects are bright, nebulous regions of gas and dust that are usually buried within dark clouds. They are formed when supersonic gas ejected from a forming protostar, or embryonic star, interacts with the surrounding interstellar medium. These young stars are often detected only in the infrared. The Spitzer image was obtained with the infrared array camera. Emission at 3.6 microns is shown as blue, emission from 4.5 and 5.8 microns has been combined as green, and 8.0 micron emission is depicted as red. HH 46/47 is a striking example of a low mass protostar ejecting a jet and creating a bipolar, or two-sided, outflow. The central protostar lies inside a dark cloud (known as a 'Bok globule') which is illuminated by the nearby Gum Nebula. Located at a distance of 1140 light-years and found in the constellation Vela, the protostar is hidden from view in the visible-light image (inset). With Spitzer, the star and its dazzling jets of molecular gas appear with clarity. The 8-micron channel of the infrared array camera is sensitive to emission from polycyclic aromatic hydrocarbons. These organic molecules, comprised of carbon and hydrogen, are excited by the surrounding radiation field and become luminescent, accounting for the reddish cloud. Note that the boundary layer of the 8-micron emission corresponds to the lower right edge of the dark cloud in the visible-light picture. Outflows are fascinating objects, since they characterize one of the most energetic phases of the formation of low-mass stars (like our Sun). The jets arising from these protostars can reach sizes of trillions of miles and velocities of hundreds of thousands miles per hour. Outflows are clear evidence of the presence of a process that creates supersonic beams of gas. This mechanism is tightly bound to the presence of circumstellar discs which surround the young stars. Such discs are likely to contain the materials from which planetary systems form. Our Sun probably underwent a similar process some 4.5 billion years ago. Hence the interest in understanding how quickly and efficiently this mass accretion and loss process takes place in protostars.
Herbig-Haro 46/47
Title Herbig-Haro 46/47
Description This 18-second animation zooms in on Herbig-Haro 46/47 and its embedded protostar with molecular outflows. Spitzer/IRAC lifts the cosmic veil and transforms the dark and opaque cloud seen at visible light wavelengths to a spectacular view of a previously unseen protostar and its bipolar outflows.
Lifting the Cosmic Veil
Title Lifting the Cosmic Veil
Description The first images from the Spitzer Space Telescope, the fourth element of NASA's Great Observatories program.
Combined Chandra X-ray Image …
Name Combined Chandra X-ray Image of Vela Pulsar Jet
Individual Chandra Stills of …
Name Individual Chandra Stills of Vela Movie
Optical Image of Vela Supern …
Name Optical Image of Vela Supernova Remnant
Chandra X-ray Image with Sca …
Name Chandra X-ray Image with Scale Bar
Crab Nebula and the Vela sup …
Name Crab Nebula and the Vela supernova remnants
Vela Pulsar Animations
Name Vela Pulsar Animations
Chandra X-ray Movie of Vela …
Name Chandra X-ray Movie of Vela Pulsar Jet
Animations of Vela Pulsar Je …
Name Animations of Vela Pulsar Jet
Chandra Spacecraft Animation
Name Chandra Spacecraft Animation
Vela Pulsar: Chandra Reveals …
Name Vela Pulsar: Chandra Reveals a Compact Nebula Created by a Shooting Neutron Star
Category Neutron Stars/X-ray Binaries
Release Date June 06, 2000
Vela Pulsar: Wide-Angle View …
Name Vela Pulsar: Wide-Angle View Of Vela Pulsar
Category Neutron Stars/X-ray Binaries
Release Date July 02, 2001
Vela Pulsar Jet: Firehose-Li …
Name Vela Pulsar Jet: Firehose-Like Jet Observed In Action
Category Neutron Stars
Release Date June 30, 2003
Image is 3.5 arcmin on a sid …
Name Image is 3.5 arcmin on a side., Vela Pulsar with Arrow
Image is 3.5 arcmin on a sid …
Name Image is 3.5 arcmin on a side., Vela Pulsar Close Up
Image is 30 arcmin, insert i …
Name Image is 30 arcmin, insert is 3.5 arcmin on a side., Vela Pulsar Composite
Vela Pulsar Midrange
Name Vela Pulsar Midrange
Vela (the sail)
Name Vela (the sail)
Dr. Robert A. Frosch
Title Dr. Robert A. Frosch
Full Description NASA's fifth administrator was Dr. Robert A. Frosch. Born and raised in New York, Dr. Frosch attended Columbia University where he received his undergraduate and graduate degrees in theoretical physics. After graduating Dr. Frosch went to work for Hudson Laboratories where he eventually became the director. In September 1963 Dr. Frosch moved to Washington, DC, to serve as Director of Nuclear Test Detection (Project VELA) for the Advanced Research Projects Agency. In 1966, after serving as the deputy director of the Advanced Research Projects Agency, Dr. Frosch became Assistant Secretary of the Navy for Research and Development. During the 1970's Dr. Frosch served as the Assistant Secretary General of the United Nations. As NASA Administrator during the Carter Administration (1977- 1981), Dr. Frosch oversaw the continuation of Space Shuttle development. He retired from NASA in 1981 to serve as Vice President for Research at the General Motors Research Laboratories.
Date UNKNOWN
NASA Center Headquarters
Supernova Shock Wave Paints …
Title Supernova Shock Wave Paints Cosmic Portrait
General Information What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. Back to top [ #top ]
Supernova Shock Wave Paints …
Title Supernova Shock Wave Paints Cosmic Portrait
General Information What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. Back to top [ #top ]
Supernova Shock Wave Paints …
Title Supernova Shock Wave Paints Cosmic Portrait
General Information What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. Back to top [ #top ]
Supernova Shock Wave Paints …
Title Supernova Shock Wave Paints Cosmic Portrait
General Information What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. Back to top [ #top ]
Shuttle Atlantis Landing at …
Photo Description NASA's Space Shuttle Atlantis touched down on the lakebed runway at Edwards Air Force Base in California's Mojave Desert Tuesday, 3 December 1985 at 1:33:49 p.m. Pacific Standard Time, concluding the STS 61-B international mission. The eight-day mission successfully deployed three communications satellites including the Mexican Morelos B, the Australian Aussat 2 and an RCA Satcom K-2 satellite. In addition, two spacewalks were performed to experiment with construction of structures in space. Crew of the 61-B mission included Commander Brewster H. Shaw, Jr., Pilot Bryan D. O'Connor, Mission Specialists Mary L. Cleave, Sherwood C. Spring and Jerry L. Ross, and Payload Specialists Rudolfo Neri Vela of Mexico and Charles Walker of McDonnell Douglas Astronautics Co.
Project Description 470,000 pounds. The engines burn a mixture of liquid oxygen and liquid hydrogen. In orbit, the Space Shuttles circle the earth at a speed of 17,500 miles per hour with each orbit taking about 90 minutes. A Space Shuttle crew sees a sunrise or sunset every 45 minutes. When Space Shuttle flights began in April 1981, Dryden Flight Research Center, Edwards, California, was the primary landing site for the Shuttles. Now Kennedy Space Center, Florida, is the primary landing site with Dryden remaining as the principal alternate landing site., Space Shuttles are the main element of America?s Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle returns to Earth and can be reused on future flights. Some of these orbital laboratories, like the Spacelab, provide facilities for several specialists to conduct experiments in such fields as medicine, astronomy, and materials manufacturing. Some types of satellites deployed by Space Shuttles include those involved in environmental and resources protection, astronomy, weather forecasting, navigation, oceanographic studies, and other scientific fields. The Space Shuttles can also launch spacecraft into orbits higher than the Shuttle?s altitude limit through the use of Inertial Upper Stage (IUS) propulsion units. After release from the Space Shuttle payload bay, the IUS is ignited to carry the spacecraft into deep space. The Space Shuttles are also being used to carry elements of the International Space Station into space where they are assembled in orbit. The Space Shuttles were built by Rockwell International?s Space Transportation Systems Division, Downey, California. Rockwell?s Rocketdyne Division (now part of Boeing) builds the three main engines, and Thiokol, Brigham City, Utah, makes the solid rocket booster motors. Martin Marietta Corporation (now Lockheed Martin), New Orleans, Louisiana, makes the external tanks. Each orbiter (Space Shuttle) is 121 feet long, has a wingspan of 78 feet, and a height of 57 feet. The Space Shuttle is approximately the size of a DC-9 commercial airliner and can carry a payload of 65,000 pounds into orbit. The payload bay is 60 feet long and 15 feet in diameter. Each main engine is capable of producing a sea level thrust of 375,000 pounds and a vacuum (orbital) thrust of
Photo Date 1985
Image of the Vela Supernova …
Name of Image Image of the Vela Supernova Remnant Taken by the High Energy Astronomy Observatory (HEAO)-2
Date of Image 1980-01-01
Full Description Like the Crab Nebula, the Vela Supernova Remnant has a radio pulsar at its center. In this image taken by the High Energy Astronomy Observatory (HEAO)-2/Einstein Observatory, the pulsar appears as a point source surrounded by weak and diffused emissions of x-rays. HEAO-2's computer processing system was able to record and display the total number of x-ray photons (a tiny bundle of radiant energy used as the fundamental unit of electromagnetic radiation) on a scale along the margin of the picture. The HEAO-2, the first imaging and largest x-ray telescope built to date, was capable of producing actual photographs of x-ray objects. Shortly after launch, the HEAO-2 was nicknamed the Einstein Observatory by its scientific experimenters in honor of the centernial of the birth of Albert Einstein, whose concepts of relativity and gravitation have influenced much of modern astrophysics, particularly x-ray astronomy. The HEAO-2, designed and developed by TRW, Inc. under the project management of the Marshall Space Flight Center, was launched aboard an Atlas/Centaur launch vehicle on November 13, 1978.
STS-61B Astronaut Ross Durin …
Name of Image STS-61B Astronaut Ross During ACCESS Extravehicular Activity
Date of Image 1985-11-30
Full Description The crew assigned to the STS-61B mission included Bryan D. O?Conner, pilot, Brewster H. Shaw, commander, Charles D. Walker, payload specialist, mission specialists Jerry L. Ross, Mary L. Cleave, and Sherwood C. Spring, and Rodolpho Neri Vela, payload specialist. Launched aboard the Space Shuttle Atlantis November 28, 1985 at 7:29:00 pm (EST), the STS-61B mission?s primary payload included three communications satellites: MORELOS-B (Mexico), AUSSAT-2 (Australia), and SATCOM KU-2 (RCA Americom). Two experiments were conducted to test assembling erectable structures in space: EASE (Experimental Assembly of Structures in Extravehicular Activity), and ACCESS (Assembly Concept for Construction of Erectable Space Structure). In a joint venture between NASA/Langley Research Center in Hampton, VA and the Marshall Space Flight Center (MSFC), ACCESS and EASE were developed and demonstrated at MSFC's Neutral Buoyancy Simulator (NBS). In this STS-61B onboard photo, astronaut Ross was working on the ACCESS experiment during an Extravehicular Activity (EVA). The primary objective of this experiment was to test the ACCESS structural assembly concept for suitability as the framework for larger space structures and to identify ways to improve the productivity of space construction.
STS-61B Astronaut Ross Works …
Name of Image STS-61B Astronaut Ross Works on Assembly Concept for Construction of Erectable Space Structure (ACCESS)
Date of Image 1985-11-30
Full Description The crew assigned to the STS-61B mission included Bryan D. O?Conner, pilot, Brewster H. Shaw, commander, Charles D. Walker, payload specialist, mission specialists Jerry L. Ross, Mary L. Cleave, and Sherwood C. Spring, and Rodolpho Neri Vela, payload specialist. Launched aboard the Space Shuttle Atlantis November 28, 1985 at 7:29:00 pm (EST), the STS-61B mission?s primary payload included three communications satellites: MORELOS-B (Mexico), AUSSAT-2 (Australia), and SATCOM KU-2 (RCA Americom). Two experiments were conducted to test assembling erectable structures in space: EASE (Experimental Assembly of Structures in Extravehicular Activity), and ACCESS (Assembly Concept for Construction of Erectable Space Structure). In a joint venture between NASA/Langley Research Center in Hampton, Virginia and the Marshall Space Flight Center (MSFC), EASE and ACCESS were developed and demonstrated at MSFC's Neutral Buoyancy Simulator (NBS). In this STS-61B onboard photo astronaut Ross, located on the Manipulator Foot Restraint (MFR) over the cargo bay, erects ACCESS. The primary objective of this experiment was to test the structural assembly concepts for suitability as the framework for larger space structures and to identify ways to improve the productivity of space construction.
Ross Works on the Assembly C …
Name of Image Ross Works on the Assembly Concept for Construction of Erectable Space Structure (ACCESS) During STS-61B Flight
Date of Image 1985-11-30
Full Description The crew assigned to the STS-61B mission included Bryan D. O?Conner, pilot, Brewster H. Shaw, commander, Charles D. Walker, payload specialist, mission specialists Jerry L. Ross, Mary L. Cleave, and Sherwood C. Spring, and Rodolpho Neri Vela, payload specialist. Launched aboard the Space Shuttle Atlantis November 28, 1985 at 7:29:00 pm (EST), the STS-61B mission?s primary payload included three communications satellites: MORELOS-B (Mexico), AUSSAT-2 (Australia), and SATCOM KU-2 (RCA Americom). Two experiments were conducted to test assembling erectable structures in space: EASE (Experimental Assembly of Structures in Extravehicular Activity), and ACCESS (Assembly Concept for Construction of Erectable Space Structure). In a joint venture between NASA/Langley Research Center in Hampton, Virginia, and the Marshall Space Flight Center (MSFC), EASE and ACCESS were developed and demonstrated at MSFC's Neutral Buoyancy Simulator (NBS). In this STS-61B onboard photo, astronaut Ross works on ACCESS high above the orbiter. The primary objective of these experiments was to test the structural assembly concepts for suitability as the framework for larger space structures and to identify ways to improve the productivity of space construction.
STS-61B Astronaut Spring Dur …
Name of Image STS-61B Astronaut Spring During EASE Extravehicular Activity (EVA)
Date of Image 1985-11-30
Full Description The crew assigned to the STS-61B mission included Bryan D. O?Conner, pilot, Brewster H. Shaw, commander, Charles D. Walker, payload specialist, mission specialists Jerry L. Ross, Mary L. Cleave, and Sherwood C. Spring, and Rodolpho Neri Vela, payload specialist. Launched aboard the Space Shuttle Atlantis November 28, 1985 at 7:29:00 pm (EST), the STS-61B mission?s primary payload included three communications satellites: MORELOS-B (Mexico), AUSSAT-2 (Australia), and SATCOM KU-2 (RCA Americom). Two experiments were conducted to test assembling erectable structures in space: EASE (Experimental Assembly of Structures in Extravehicular Activity), and ACCESS (Assembly Concept for Construction of Erectable Space Structure). In a joint venture between NASA/Langley Research Center in Hampton, Virginia, and the Marshall Space Flight Center (MSFC), the EASE and ACCESS were developed and demonstrated at MSFC's Neutral Buoyancy Simulator (NBS). In this STS-61B onboard photo, astronaut Spring was working on the EASE during an Extravehicular Activity (EVA). The primary objective of this experiment was to test the structural assembly concepts for suitability as the framework for larger space structures and to identify ways to improve the productivity of space construction.
STS-61B Astronaut Ross Durin …
Name of Image STS-61B Astronaut Ross During ACCESS Extravehicular Activity
Date of Image 1985-11-30
Full Description The crew assigned to the STS-61B mission included Bryan D. O?Conner, pilot, Brewster H. Shaw, commander, Charles D. Walker, payload specialist, mission specialists Jerry L. Ross, Mary L. Cleave, and Sherwood C. Spring, and Rodolpho Neri Vela, payload specialist. Launched aboard the Space Shuttle Atlantis November 28, 1985 at 7:29:00 pm (EST), the STS-61B mission?s primary payload included three communications satellites: MORELOS-B (Mexico), AUSSAT-2 (Australia), and SATCOM KU-2 (RCA Americom). Two experiments were conducted to test assembling erectable structures in space: EASE (Experimental Assembly of Structures in Extravehicular Activity), and ACCESS (Assembly Concept for Construction of Erectable Space Structure). In a joint venture between NASA/Langley Research Center in Hampton, Virginia and the Marshall Space Flight Center (MSFC), EASE and ACCESS were developed and demonstrated at MSFC's Neutral Buoyancy Simulator (NBS). The primary objective of this experiment was to test the structural assembly concepts for suitability as the framework for larger space structures and to identify ways to improve the productivity of space construction. In this STS-61B onboard photo, astronaut Ross was working on the ACCESS experiment during an Extravehicular Activity (EVA).
Astronaut Ross Approaches As …
Name of Image Astronaut Ross Approaches Assembly Concept for Construction of Erectable Space Structure (ACCESS)
Date of Image 0000-00-00
Full Description The crew assigned to the STS-61B mission included Bryan D. O?Conner, pilot, Brewster H. Shaw, commander, Charles D. Walker, payload specialist, mission specialists Jerry L. Ross, Mary L. Cleave, and Sherwood C. Spring, and Rodolpho Neri Vela, payload specialist. Launched aboard the Space Shuttle Atlantis November 28, 1985 at 7:29:00 pm (EST), the STS-61B mission?s primary payload included three communications satellites: MORELOS-B (Mexico), AUSSAT-2 (Australia), and SATCOM KU-2 (RCA Americom). Two experiments were conducted to test assembling erectable structures in space: EASE (Experimental Assembly of Structures in Extravehicular Activity), and ACCESS (Assembly Concept for Construction of Erectable Space Structure). In a joint venture between NASA/Langley Research Center in Hampton, Virginia, and the Marshall Space Flight Center (MSFC), EASE and ACCESS were developed and demonstrated at MSFC's Neutral Buoyancy Simulator (NBS). In this STS-61B onboard photo, astronaut Ross, perched on the Manipulator Foot Restraint (MFR) approaches the erected ACCESS. The primary objective of these experiments was to test the structural assembly concepts for suitability as the framework for larger space structures and to identify ways to improve the productivity of space construction.
STS-61B Astronauts Ross and …
Name of Image STS-61B Astronauts Ross and Spring Work on Experimental Assembly of Structures in Extravehicular Activity (EASE)
Date of Image 1985-11-30
Full Description The crew assigned to the STS-61B mission included Bryan D. O?Conner, pilot, Brewster H. Shaw, commander, Charles D. Walker, payload specialist, mission specialists Jerry L. Ross, Mary L. Cleave, and Sherwood C. Spring, and Rodolpho Neri Vela, payload specialist. Launched aboard the Space Shuttle Atlantis November 28, 1985 at 7:29:00 pm (EST), the STS-61B mission?s primary payload included three communications satellites: MORELOS-B (Mexico), AUSSAT-2 (Australia), and SATCOM KU-2 (RCA Americom). Two experiments were conducted to test assembling erectable structures in space: EASE (Experimental Assembly of Structures in Extravehicular Activity), and ACCESS (Assembly Concept for Construction of Erectable Space Structure). In a joint venture between NASA/Langley Research Center in Hampton, Virginia, and the Marshall Space Flight Center (MSFC), EASE and ACCESS were developed and demonstrated at MSFC's Neutral Buoyancy Simulator (NBS). This STS-61B onboard photo depicts astronauts Ross and Spring working on EASE. The primary objective of these experiments was to test the structural assembly concepts for suitability as the framework for larger space structures and to identify ways to improve the productivity of space construction.
STS-61B Crew Portrait
Name of Image STS-61B Crew Portrait
Date of Image 1985-11-01
Full Description The crew assigned to the STS-61B mission included (kneeling left to right) Bryan D. O?conner, pilot, and Brewster H. Shaw, commander. On the back row, left to right, are Charles D. Walker, payload specialist, mission specialists Jerry L. Ross, Mary L. Cleave, and Sherwood C. Spring, and Rodolpho Neri Vela, payload specialist. Launched aboard the Space Shuttle Atlantis November 28, 1985 at 7:29:00 pm (EST), the STS-61B mission?s primary payload included three communications satellites: MORELOS-B (Mexico), AUSSAT-2 (Autralia), and SATCOM KU-2 (RCA Americom. Two experiments were conducted to test assembling erectable structures in space: EASE (Experimental Assembly of Structures in Extravehicular Activity), and ACCESS (Assembly Concept for Construction of Erectable Space Structure). In a joint venture between NASA/Langley Research Center in Hampton, VA and Marshall Space Flight Center (MSFC), the Assembly Concept for Construction of Erectable Space Structures (ACCESS) was developed and demonstrated at MSFC's Neutral Buoyancy Simulator (NBS). The primary objective of this experiment was to test the ACCESS structural assembly concept for suitability as the framework for larger space structures and to identify ways to improve the productivity of space construction.
The Gum Nebula
Title The Gum Nebula
Explanation Named for Australian astronomer Colin Stanley Gum [ http://en.wikipedia.org/wiki/Colin_Stanley_Gum ] (1924-1960), The Gum Nebula [ http://www.southernskyphoto.com/southern_sky/gum_nebula.htm ] is so large and close it is actually hard to see. In fact [ http://antwrp.gsfc.nasa.gov/apod/ap020217.html ], we are only about 450 light-years from the front edge and 1,500 light-years from the back edge of this cosmic cloud of glowing hydrogen gas. Covered in this 41 degree-wide [ http://canopus.physik.uni-potsdam.de/~axm/ photo.cgi?Image=images/Vela_50mm_HaRGB_1000 ] mosaic of H-alpha [ http://antwrp.gsfc.nasa.gov/apod/ap051223.html ] images, the faint emission region is otherwise easy to lose against the background of Milky Way stars. The complex [ http://adsabs.harvard.edu/cgi-bin/ nph-bib_query?bibcode=1993A%26A...280..231S ] nebula is thought to be a supernova remnant [ http://chandra.harvard.edu/xray_sources/ supernovas.html ] over a million years old, sprawling across [ http://hawastsoc.org/deepsky/car/index.html#Myth ] the southern constellations Vela and Puppis. Sliding your cursor over this spectacular wide field view will reveal the location of objects embedded in The Gum Nebula, including the Vela supernova remnant [ http://www.aao.gov.au/images/captions/ uks002.html ].
Giant Cluster Bends, Breaks …
Title Giant Cluster Bends, Breaks Images
Explanation What are those strange blue objects? Many are images of a "single," unusual, beaded, blue, ring-like galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap981219.html ] which just happens to line-up behind a giant cluster of galaxies. [ http://antwrp.gsfc.nasa.gov/apod/clusters_of_galaxies.html ] Cluster galaxies here appear yellow and -- together with the cluster's dark matter [ http://antwrp.gsfc.nasa.gov/apod/ap960419.html ] -- act as a gravitational lens [ http://antwrp.gsfc.nasa.gov/apod/ap951220.html ]. A gravitational lens [ http://cfa-www.harvard.edu/~jcohn/lens.html ] can create several images of background galaxies, analogous to the many points of light one would see while looking through a wine glass [ http://vela.astro.ulg.ac.be/themes/extragal/gravlens/bibdat/engl/DE/didac.html ] at a distant street light. The distinctive shape of this background galaxy [ http://www.journals.uchicago.edu/ApJ/journal/issues/ApJL/v461n2/5782/5782.html ] -- which is probably just forming -- has allowed astronomers to deduce that it has separate images at 4, 8, 9 and 10 o'clock, from the center of the cluster. Possibly even the blue smudge just left of center is yet another image! This spectacular photo from the Hubble Space Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap970306.html ] was taken in October 1994.
Vela Pulsar: Neutron Star-Ri …
Title Vela Pulsar: Neutron Star-Ring-Jet
Explanation This stunning image [ http://chandra.harvard.edu/photo/cycle1/vela/ ] from the orbiting Chandra X-ray Observatory [ http://chandra.harvard.edu/index.html ] is centered on the Vela pulsar -- the collapsed stellar core within the Vela supernova remnant [ http://antwrp.gsfc.nasa.gov/apod/ap960612.html ] some 800 light-years distant. The Vela pulsar is a neutron star [ http://imagine.gsfc.nasa.gov/docs/science/know_l1/ pulsars.html ]. More massive than the Sun, it has the density of an atomic nucleus. About 12 miles in diameter it spins 10 times a second as it hurtles through the supernova debris cloud [ http://antwrp.gsfc.nasa.gov/apod/ap980425.html ]. The pulsar's [ http://www.jb.man.ac.uk/~pulsar/Education/Sounds/ sounds.html ] electric and magnetic fields accelerate particles to nearly the speed of light, powering the compact x-ray [ http://imagine.gsfc.nasa.gov/docs/science/know_l1/ history1_xray.html ] emission nebula revealed in the Chandra picture. The cosmic crossbow shape is over 0.2 light-years across, composed of an arrow-like jet emanating from the polar region of the neutron star [ http://astro.uchicago.edu/home/web/miller/nstar.html ] and bow-like inner and outer arcs believed to be the edges of tilted rings of x-ray emitting high energy particles. Impressively, the swept back compact nebula indicates the neutron star is moving up and to the right in this picture, exactly along the direction of the x-ray jet. The Vela pulsar (and associated supernova remnant [ http://www.seds.org/billa/twn/velax.html ]) was created by a massive star which exploded over 10,000 years ago. Its awesome x-ray rings and jet are reminiscent of another well-known pulsar powered system, the Crab Nebula [ http://antwrp.gsfc.nasa.gov/apod/ap990929.html ].
Gamma-Ray Burst: A Milestone …
Title Gamma-Ray Burst: A Milestone Explosion
Explanation Gamma-Ray Bursts (GRBs) were discovered [ http://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/grbhist.html ] by accident. Thirty three years ago today, satellites first recorded a GRB [ http://antwrp.gsfc.nasa.gov/htmltest/ jbonnell/www/grbhist.html#firstburst ]. The data plotted here show that the count rate of the satellite gamma-ray instrument abruptly jumped [ http://antwrp.gsfc.nasa.gov/apod/ap991104.html ] indicating a sudden flash of gamma-rays. The Vela satellites [ http://leonardo.jpl.nasa.gov/msl/QuickLooks/velaQL.html ] that detected this and other GRBs were developed to test technology to monitor nuclear test ban treaties [ http://www.state.gov/www/global/arms/treaties/ltbt1.html ]. With on board sensors they watched [ http://antwrp.gsfc.nasa.gov/apod/ap951105.html ] for brief x-ray [ http://imagine.gsfc.nasa.gov/docs/science/know_l2/ history_xray.html ] and gamma-ray [ http://imagine.gsfc.nasa.gov/docs/science/know_l2/ history_gamma.html ] flashes, the telltale signatures of nuclear [ http://www.em.doe.gov/timeline/ ] explosions. As intended, the Velas found flashes of gamma-rays - but not from nuclear detonations near Earth. Instead, the flashes were determined to come from deep space! Dubbed "cosmic gamma-ray bursts" [ http://antwrp.gsfc.nasa.gov/apod/ap961123.html ] they are now known [ http://antwrp.gsfc.nasa.gov/diamond_jubilee/ debate_1995.html ] to be the most powerful explosions originating in distant galaxies. What could power a gamma-ray burst [ http://www.sciam.com/0797issue/ 0797fishman.html ]?
ROSAT Explores The X-Ray Sky
Title ROSAT Explores The X-Ray Sky
Explanation Launched in 1990, the orbiting ROSAT observatory [ http://heasarc.gsfc.nasa.gov/docs/rosat/rosat.html ] explored the Universe by viewing the entire sky in x-rays [ http://imagine.gsfc.nasa.gov/docs/science/know_l1/ history1_xray.html ] -- photons with about 1,000 times more energy than visible light. This ROSAT survey [ http://www.xray.mpe.mpg.de/rosat/survey/sxrb/12/ass.html ] produced the sharpest, most sensitive image of the x-ray sky to date. The all-sky image is shown with the plane of our Milky Way Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap980523.html ] running horizontally through the center. Both x-ray brightness and relative energy are represented with red, green, and blue colors indicating three x-ray energy ranges (from lowest to highest). Bright x-ray spots near the galactic plane are within our own Milky Way. The brightest region (right of center) is toward the Vela Pulsar [ http://antwrp.gsfc.nasa.gov/apod/ap000609.html ] and the Puppis supernova remnant [ http://antwrp.gsfc.nasa.gov/apod/ap991209.html ]. Bright sources beyond our Galaxy are also apparent, notably the Virgo cluster of galaxies [ http://www.seds.org/messier/more/virgo.html ] (near top right) and the Large Magellanic Cloud (LMC) [ http://www.seds.org/messier/xtra/ngc/lmc.html ]. The LMC is easy to find here as several of the black stripes (blank areas caused by missing data) seem to converge on its position (lower right). Over large areas of the sky a general diffuse background of x-rays [ http://chandra.harvard.edu/press/00_releases/ press_011400bg.html ] dominates. Hot gas in our own Galaxy provides much of this background and gives rise to the grand looping structures [ http://antwrp.gsfc.nasa.gov/apod/ap990503.html ] visible in the direction of the galactic center (image center). Unresolved extragalactic sources also add to this background, particularly above and below the plane. Despite the x-ray sky's exotic appearance, a very familiar feature is visible - the gas and dust clouds which line the plane of our galaxy absorb x-rays as well as optical light and produce the dark bands running through the galactic center [ http://antwrp.gsfc.nasa.gov/apod/ap000629.html ].
The Gum Nebula Supernova Rem …
Title The Gum Nebula Supernova Remnant
Explanation Because the Gum Nebula is the closest supernova remnant [ http://antwrp.gsfc.nasa.gov/apod/supernova_remnants.html ], it is actually hard to see. Spanning 40 degrees [ http://math.rice.edu/~pcmi/sphere/drg_txt.html ] across the sky, the nebula is so large and faint [ http://antwrp.gsfc.nasa.gov/apod/ap000412.html ] it is easily lost in the din of a bright and complex background. The Gum Nebula [ http://www.britannica.com/bcom/eb/article/idxref/3/0,5716,363760,00.html ], highlighted nicely in the above wide angle photograph [ http://www.celestialimage.com/page107.html ], is so close that we are much nearer the front edge than the back edge, each measuring 450 and 1500 light years [ http://chandra.harvard.edu/photo/cosmic_distance.html ] respectively. The complex nebula [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1993A%26A...280..231S ] lies in the direction of the constellations [ http://aibn47.astro.uni-bonn.de/~gallery/constellations/const.html ] of Puppis [ http://www.astro.wisc.edu/~dolan/constellations/constellations/Puppis.html ] and Vela [ http://www.astro.wisc.edu/~dolan/constellations/constellations/Vela.html ]. Oddly, much remains unknown about the Gum Nebula [ http://www.edpsciences.org/articles/astro/abs/1997/07/ads1235/ads1235.html ], including the timing and even number of supernova explosions [ http://observe.ivv.nasa.gov/nasa/space/stellardeath/stellardeath_3.html ] that formed it.
Vela Supernova Remnant in Vi …
Title Vela Supernova Remnant in Visible Light
Explanation The explosion is over but the consequences continue. About eleven thousand years ago a star in the constellation of Vela [ http://www.hawastsoc.org/deepsky/vel/index.html ] could be seen to explode [ http://www.youtube.com/watch?v=gL1xUWgBlFw ], creating a strange point of light briefly visible to humans living near the beginning of recorded history [ http://en.wikipedia.org/wiki/Cave_painting ]. The outer layers of the star crashed into the interstellar medium [ http://antwrp.gsfc.nasa.gov/apod/ap020210.html ], driving a shock wave [ http://antwrp.gsfc.nasa.gov/apod/ap020313.html ] that is still visible today. A roughly spherical, expanding shock wave is visible in X-rays [ http://antwrp.gsfc.nasa.gov/apod/ap960612.html ]. The above image [ http://www.skyfactory.org/vela/vela.htm ] captures much of that filamentary and gigantic shock in visible light [ http://imagers.gsfc.nasa.gov/ems/visible.html ], spanning almost 100 light years [ http://chandra.harvard.edu/photo/cosmic_distance.html ] and appearing twenty times the diameter of the full moon [ http://antwrp.gsfc.nasa.gov/apod/ap051113.html ]. As gas flies away from the detonated star, it decays [ http://imagine.gsfc.nasa.gov/docs/features/exhibit/cgro_snr.html ] and reacts with the interstellar medium, producing light in many different colors and energy bands. Remaining at the center of the Vela Supernova Remnant [ http://en.wikipedia.org/wiki/Vela_Supernova_Remnant ] is a pulsar [ http://imagine.gsfc.nasa.gov/docs/science/know_l1/pulsars.html ], a star as dense as nuclear matter that completely rotates more than ten times in a single second.
Illusion and Evolution in Ga …
Title Illusion and Evolution in Galaxy Cluster Abell 2667
Explanation What's happening to the galaxies of cluster Abell 2667? On the upper left, a galaxy appears to be breaking up into small pieces, while on the far right, another galaxy appears to be stretched like taffy. To start, most of the yellowish objects in the above image [ http://www.spacetelescope.org/news/html/heic0705.html ] from the Hubble Space Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap010806.html ] are galactic members of a massive cluster of galaxies [ http://antwrp.gsfc.nasa.gov/apod/clusters_of_galaxies.html ] known as Abell 2667 [ http://en.wikipedia.org/wiki/Abell_2667 ]. The distortion of the galaxy on the upper left is real. As the galaxy plows through the intercluster medium [ http://www.physicsforums.com/archive/index.php/t-77572.html ], gas is stripped out and condenses to form bright new knots of stars. This detailed image of ram pressure [ http://en.wikipedia.org/wiki/Ram_pressure ] stripping helps astronomers understand why so many galaxies today have so little gas. The distortion of the galaxy on the far right, however, is an illusion [ http://en.wikipedia.org/wiki/Optical_illusion ]. This nearly normal galaxy is actually far behind the massive galaxy cluster. Light from this galaxy is gravitationally lensed [ http://www.astro.ucla.edu/~wright/cluster-lensing.html ] by Abell 2667, appearing much like a distant person would appear through [ http://vela.astro.ulg.ac.be/themes/extragal/gravlens/bibdat/engl/DE/didac.html ] a wine glass. Each distorted galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap040807.html ] gives important clues about how galaxies and clusters of galaxies evolve [ http://en.wikipedia.org/wiki/Galaxy_formation_and_evolution ].
Pulsar Wind in the Vela Nebu …
Title Pulsar Wind in the Vela Nebula
Explanation The Vela pulsar was born [ http://antwrp.gsfc.nasa.gov/apod/ap980425.html ] 10,000 years ago at the center of a supernova -- an exploding star [ http://imagine.gsfc.nasa.gov/docs/science/know_l2/ supernovae.html ]. In this Chandra Observatory x-ray image [ http://chandra.harvard.edu/photo/cycle1/velawv/ index.html ], the pulsar still produces a glowing nebula at the heart of the expanding cloud of stellar debris. The pulsar [ http://www.jb.man.ac.uk/~pulsar/Education/Sounds/ sounds.html ] itself is a neutron star [ http://heasarc.gsfc.nasa.gov/docs/objects/binaries/ neutron_star_structure.html ], formed as the stellar core was compacted [ http://observe.ivv.nasa.gov/nasa/space/stellardeath/ stellardeath_3a.html ] to nuclear densities. With a strong magnetic field, approximately the mass of the Sun, and a diameter of about 20 kilometers, the Vela pulsar rotates 11 times "a second". The sharp Chandra image aids astronomers [ http://xxx.lanl.gov/abs/astro-ph/0105128 ] in understanding such extreme systems as efficient high-voltage generators [ http://chandra.harvard.edu/chronicle/0201/vela.html ] which drive structured winds [ http://antwrp.gsfc.nasa.gov/apod/ap000609.html ] of electrically charged particles. An x-ray bright nebula is created as the pulsar winds slam into the surrounding material. This view spans about 6 light-years across the central region of the much larger Vela supernova remnant [ http://antwrp.gsfc.nasa.gov/apod/ap960612.html ].
The Local Bubble and the Gal …
Title The Local Bubble and the Galactic Neighborhood
Explanation What surrounds the Sun in this neck of the Milky Way Galaxy [ http://www.seds.org/messier/more/mw.html ]? Our current best guess is depicted in the above map [ http://www.sigmaxi.org/amsci/articles/00articles/Frischcap3.html ] of the surrounding 1500 light year [ http://chandra.harvard.edu/photo/cosmic_distance.html ]s constructed from various observations and deductions [ http://www.sigmaxi.org/amsci/articles/00articles/Frisch.html ]. Currently, the Sun is passing through a Local Interstellar Cloud [ http://antwrp.gsfc.nasa.gov/apod/ap020210.html ] (LIC), shown in violet, which is flowing away from the Scorpius-Centaurus Association [ http://www.mpifr-bonn.mpg.de/staff/tpreibis/scocen.html ] of young stars. The LIC resides in a low-density hole in the interstellar medium [ http://spacsun.rice.edu/~twg/lism.html ] (ISM) called the Local Bubble [ http://spacsun.rice.edu/~twg/pc120.html ], shown in black. Nearby, high-density molecular clouds [ http://antwrp.gsfc.nasa.gov/apod/ap010923.html ] including the Aquila Rift [ http://www.a.phys.nagoya-u.ac.jp/~ohnishi/aquila/aquila.html ] surround star forming regions, each shown in orange. The Gum Nebula [ http://antwrp.gsfc.nasa.gov/apod/ap001107.html ], shown in green, is a region of hot ionized [ http://csep10.phys.utk.edu/astr162/lect/light/ionization.html ] hydrogen [ http://pearl1.lanl.gov/periodic/elements/1.html ] gas. Inside the Gum Nebula [ http://www.edpsciences.org/articles/astro/abs/1997/07/ads1235/ads1235.html ] is the Vela Supernova Remnant [ http://antwrp.gsfc.nasa.gov/apod/ap960612.html ], shown in pink, which is expanding to create fragmented shells of material like the LIC [ http://antwrp.gsfc.nasa.gov/apod/ap020217.html http://www-ssg.sr.unh.edu/tof/Outreach/Interstellar/index.html ]. Future observations should help astronomers discern more about the local Galactic Neighborhood [ http://www.sigmaxi.org/amsci/articles/00articles/frischmaterial.html#environment ] and how it might have affected Earth's past climate [ http://whyfiles.news.wisc.edu/017planet/gas_cloud2.html ].
Simulated Galaxy Cluster Vie …
Title Simulated Galaxy Cluster View
Explanation Stunningly detailed, this picture is a computer simulated view [ http://oposite.stsci.edu/pubinfo/pr/2002/06/ index.html ] of a cluster of galaxies [ http://antwrp.gsfc.nasa.gov/apod/ clusters_of_galaxies.html ] in the distant cosmos [ http://archive.ncsa.uiuc.edu/Cyberia/Cosmos/ HierarchUni.html ]. A large, elliptical galaxy dominates this hypothetical cluster's central region surrounded by a swarm of member galaxies. Other galaxies which lie far behind the cluster are seen as numerous visible concentric arcs [ http://antwrp.gsfc.nasa.gov/apod/ap011007.html ] - lensed by [ http://www.iam.ubc.ca/~newbury/lenses/ research.html ] the enormous gravitational [ http://vela.astro.ulg.ac.be/themes/extragal/gravlens/ bibdat/ ] field dominated by dark matter [ http://antwrp.gsfc.nasa.gov/apod/ap011024.html ] within the cluster itself. Such magnificent images are expected to be achieved by the Advanced Camera for Surveys [ http://www.ball.com/aerospace/acs.html ] (ACS), one of the upgrades [ http://sm3b.gsfc.nasa.gov/mission-critical/ objectives-part1.html ] being installed on the Hubble Space Telescope during the ongoing servicing mission [ http://spaceflight.nasa.gov/shuttle/crew/grunsfeldreports/ grunsfeldreports.html ]. Compared to Hubble's workhorse Wide Field Planetary Camera 2 [ http://hubble.stsci.edu/sci.d.tech/behind_the_pictures/ wacky_shape/constructing.shtml ] (WFPC2), whose achievements include the current deep field views [ http://www.stsci.edu/ftp/science/hdf/hdf.html ] of the Universe, the new technology ACS will be twice as sharp an imager with twice the field of view and five times the sensitivity. Along with extended views of the distant cosmos, enthusiastic astronomers also plan to use the ACS to monitor our own Solar System [ http://antwrp.gsfc.nasa.gov/apod/ap020214.html ] and to search for planets orbiting stars [ http://www.generation.net/~mariob/astro/exoplan/ intro-e.htm ] beyond the Sun.
Vela Satellites: The Watcher …
Title Vela Satellites: The Watchers
Explanation In October of 1963 the US Air Force [ http://www.dtic.dla.mil/airforcelink/ ] launched the first in a series of satellites inspired by a recently signed nuclear test ban treaty [ gopher://wealaka.okgeosurvey1.gov/11/nuke.treaties ]. Signatories of this treaty agreed not to test nuclear devices in the atmosphere or in space. These "Vela" (from the Spanish verb [ http://www.willamette.edu/~tjones/Language-Page.html ] velar, to watch) satellites were part of an unclassified program whose goal was to develop the technology to monitor nuclear tests from space. A Vela satellite [ http://heasarc.gsfc.nasa.gov/docs/heasarc/missions/vela5a.html ] is pictured above in an artist's conception, keeping watch over the Earth. The high energy radiation sensors onboard the Velas did not detect any clandestine nuclear explosions [ http://www.pal.xgw.fi/hew/ ]. Instead, in the most surprising discovery [ http://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/grbhist.html ] in the history of space based astronomy, they found bursts of gamma rays [ http://antwrp.gsfc.nasa.gov/apod/ap950827.html ] coming from deep space! The mysterious origin of these brief, intense flashes of gamma rays is one of the most hotly debated topics [ http://antwrp.gsfc.nasa.gov/diamond_jubilee/debate.html ] in modern astrophysics.
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