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Vintage Gamma-Rays
| Title |
Vintage Gamma-Rays |
| Explanation |
Gamma-rays [ http://imagine.gsfc.nasa.gov/docs/science/know_l2/ history_gamma.html ] are the most energetic form of electromagnetic radiation [ http://imagine.gsfc.nasa.gov/docs/science/know_l1/ emspectrum.html ]. But these high energy photons penetrate and interact in normal materials and cannot be focused by lenses and mirrors like those in optical telescopes. So how do you make an image in gamma-ray light [ http://imagine.gsfc.nasa.gov/docs/science/how_l1/ gamma_detectors.html ]? One way is to use a patterned mask of material which can cast gamma-ray shadows [ http://home.iae.nl/users/ferdv/shadow.htm ] on a digital detector array. The mask is called a coded aperture [ http://lheawww.gsfc.nasa.gov/docs/cai/coded.html ] and the resulting shadow patterns can be used to construct a gamma-ray image of the source. For example, consider the picture above [ http://heasarc.gsfc.nasa.gov/docs/objects/heapow/archive/ technology/isgri_first_image.html ]. In place of a coded mask [ http://swift.sonoma.edu/instruments/bat.html ], familiar objects were positioned in front of a detector array and illuminated with gamma-rays in a laboratory test. Do you recognize the shadow [ http://www.shadowradio.org/ ] image? (Click on the picture for the focused visible light image.) Destined to fly on the International Gamma-Ray Astrophysics Laboratory [ http://astro.estec.esa.nl/SA-general/Projects/Integral/ integral.html ] (INTEGRAL [ http://heasarc.gsfc.nasa.gov/docs/integral/ integralgof.html ]) satellite scheduled for launch in 2002, the detector array will be part of the imaging gamma-ray telescope, IBIS [ http://astro.estec.esa.nl/SA-general/Projects/Integral/ integ_payload_imager.html ]. |
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Vintage Gamma Rays
| Title |
Vintage Gamma Rays |
| Explanation |
Gamma-rays [ http://imagine.gsfc.nasa.gov/docs/science/know_l2/ history_gamma.html ] are the most energetic form of electromagnetic radiation [ http://imagers.gsfc.nasa.gov/ems/index.html ]. But these high energy photons penetrate and interact in normal materials and cannot be focused by lenses and mirrors like those in optical telescopes. So how do you make an image in gamma-ray light [ http://imagine.gsfc.nasa.gov/docs/science/how_l1/ gamma_detectors.html ]? One way is to use a patterned mask of material which can cast gamma-ray shadows [ http://home.iae.nl/users/ferdv/shadow.htm ] on a digital detector array. The mask is called a coded aperture [ http://lheawww.gsfc.nasa.gov/docs/cai/coded.html ] and the resulting shadow patterns can be used to construct a gamma-ray image of the source. For example, consider the picture above [ http://heasarc.gsfc.nasa.gov/docs/objects/heapow/archive/ technology/isgri_first_image.html ]. In place of a coded mask [ http://swift.gsfc.nasa.gov/scitech/instruments/ bat.html ], familiar objects were positioned in front of a detector array and illuminated with gamma-rays in a laboratory test. Do you recognize the shadow [ http://www.shadowradio.org/ ] image? (Click on the picture for the focused visible light image.) Destined to fly on the International Gamma-Ray Astrophysics Laboratory [ http://astro.estec.esa.nl/SA-general/Projects/Integral/ integral.html ] (INTEGRAL [ http://heasarc.gsfc.nasa.gov/docs/integral/ integralgof.html ]) satellite scheduled for launch in October of this year, the detector array [ http://www-dapnia.cea.fr/Phys/Sap/Actualites/ISGRI/ isgriang.shtml ] is part of the imaging gamma-ray telescope, IBIS [ http://astro.estec.esa.nl/Integral/ integ_payload_imager.html ]. |
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With a cloudy horizon scene
…
| Title |
With a cloudy horizon scene as a backdrop, the Spartan 207 free-flyer is held in the grasp of the Space Shuttle Endeavour's Remote Manipulator System (RMS) following its re-capture on May 21, 1996. |
| Description |
STS-77 ESC VIEW --- With a cloudy horizon scene as a backdrop, the Spartan 207 free-flyer is held in the grasp of the Space Shuttle Endeavour's Remote Manipulator System (RMS) following its re-capture on May 21, 1996. The view was captured with an onboard Electronic Still Camera (ESC). The six-member crew has spent a portion of the early stages of the mission in various activities involving the Spartan 207 and the related Inflatable Antenna Experiment (IAE). The Spartan project is managed by NASA's Goddard Space Flight Center (GSFC) for NASA's Office of Space Science, Washington, D.C. GMT: 09:39:35. |
| Date Taken |
1996-05-21 |
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In this medium close-up view
…
| Title |
In this medium close-up view, captured by an Electronic Still Camera (ESC), the Spartan 207 free-flyer is held in the grasp of the Space Shuttle Endeavour's Remote Manipulator System (RMS) following its re-capture on May 21, 1996. |
| Description |
STS-77 ESC VIEW --- In this medium close-up view, captured by an Electronic Still Camera (ESC), the Spartan 207 free-flyer is held in the grasp of the Space Shuttle Endeavour's Remote Manipulator System (RMS) following its re-capture on May 21, 1996. The six-member crew has spent a portion of the early stages of the mission in various activities involving the Spartan 207 and the related Inflatable Antenna Experiment (IAE). The Spartan project is managed by NASA's Goddard Space Flight Center (GSFC) for NASA's Office of Space Science, Washington, D.C. GMT: 09:38:05. |
| Date Taken |
1996-05-21 |
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The Spartan 207 free-flyer i
…
| Title |
The Spartan 207 free-flyer is held in a low-hover mode above its berth in the Space Shuttle Endeavour's cargo bay in the grasp of the Remote Manipulator System (RMS). |
| Description |
STS-77 ESC VIEW --- The Spartan 207 free-flyer is held in a low-hover mode above its berth in the Space Shuttle Endeavour's cargo bay in the grasp of the Remote Manipulator System (RMS). The Spacehab module can be seen in the foreground. The free-flyer was re-captured by the six crew members on May 21, 1996. The crew has spent a portion of the early stages of the mission in various activities involving the Spartan 207 and the related Inflatable Antenna Experiment (IAE). The Spartan project is managed by NASA's Goddard Space Flight Center (GSFC) for NASA's Office of Space Science, Washington, D.C. GMT: 09:51:50. |
| Date Taken |
1996-05-21 |
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The Spartan 207 free-flyer i
…
| Title |
The Spartan 207 free-flyer is held in a low-hover mode above its berth in the Space Shuttle Endeavour's cargo bay in the grasp of the Remote Manipulator System (RMS). |
| Description |
STS-77 ESC VIEW --- The Spartan 207 free-flyer is held in a low-hover mode above its berth in the Space Shuttle Endeavour's cargo bay in the grasp of the Remote Manipulator System (RMS). The free-flyer was re-captured by the six crew members on May 21, 1996. The crew has spent a portion of the early stages of the mission in various activities involving the Spartan 207 and the related Inflatable Antenna Experiment (IAE). The Spartan project is managed by NASA's Goddard Space Flight Center (GSFC) for NASA's Office of Space Science, Washington, D.C. GMT: 09:51:29. |
| Date Taken |
1996-05-21 |
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