|
News Archive |
|
News Archive
SIRTF is designed to explore the cosmos in the infrared portion of the electromagnetic spectrum, where it will study young galaxies and stars, dust disks around stars where planets may be forming, objects hidden by dust, and some of the most distant objects in the Universe.
IRAC, one of three instruments to be installed and flown on SIRTF, will be used for a wide variety of astronomical investigations during SIRTF's mission, including study of the early universe, searching for brown dwarfs and protoplanets, and the study of galaxies.
IRAC was originally scheduled for shipment from NASA's Goddard Space Flight Center, Greenbelt, MD, to Ball Aerospace in Boulder, CO, on April 1, 2000, for integration into the Cryogenic Telescope Assembly (CTA). After this initial assembly, it was to go through testing to simulate the vibration it will receive during launch and the conditions it will experience in space (also called "environmental testing"), before being shipped to Lockheed Martin in Sunnyvale, CA, for integration with the SIRTF spacecraft. However, a portion of the IRAC was not shipped to Ball until September 16, with the remaining components to be shipped this winter.
The primary cause of the delay of final shipment of the IRAC is a problem with the software program residing within the electronics that controls the instrument. During testing, it was found that of the IRAC software program did not perform as expected in a number of ways. Work continues to fix the software problems. In addition, hardware problems were identified and fixed over the past several months, which also contributed to the delay. There is one remaining hardware problem in the IRAC electronics that is currently being fixed - the replacement of capacitors due a faulty production lot by the supplier.
SIRTF is the fourth and final of NASA's Great Observatories, which include the Hubble Space Telescope, the Chandra X-ray Observatory, and the Compton Gamma Ray Observatory. NASA's Jet Propulsion Laboratory (JPL), Pasadena, Calif. manages the SIRTF mission for NASA's Office of Space Science, Washington, D.C. JPL is managed by the California Institute of Technology in Pasadena.