משתמש:Jacobs/ארגז חול2.5
שגיאות פרמטריות בתבנית:רכב חלל
פרמטרים ריקים [ מספר זיהוי, מיקום ] לא מופיעים בהגדרת התבנית
פרמטרים [ אורך חיים, סוג המשימה, כתובית ] לא מופיעים בהגדרת התבנית
פרמטרים ריקים [ 1 ] לא מופיעים בהגדרת התבנית
| מידע כללי | |
|---|---|
| סוכנות חלל | נאס"א |
| יצרן | לוקהיד מרטין |
| תאריך שיגור | 25 באוגוסט 2003 |
| משגר | דלתא II |
| http://www.spitzer.caltech.edu/ | |
| משימה | |
| לוויין של | השמש |
| מסלול | הליוצנטרי |
| זמן הקפה | שנה |
| מידע טכני | |
| משקל בשיגור | 950 |
The Far Ultraviolet Spectroscopic Explorer (FUSE) is a space-based telescope operated by the Johns Hopkins University Applied Physics Laboratory. FUSE was launched on a Delta II rocket on June 24, 1999, as a part of NASA's Origins program. FUSE detected light in the far ultraviolet portion of the electromagnetic spectrum, between 90.5-119.5 nanometres, which is mostly unobservable by other telescopes. Its primary mission was to characterize universal deuterium in an effort to learn about the stellar processing times of deuterium left over from the Big Bang.
FUSE resides in a low Earth orbit, approximately 760 km (410 nmi) in altitude, with an inclination of 25 degrees and just less than a 100 minute orbital period. Its Explorer designation is Explorer 77.
On July 12, 2007, FUSE's final reaction wheel, which is required for accurately pointing a spacecraft, failed and efforts to restart it were unsuccessful. An announcement was made on September 6 that because the fine control needed to perform its mission had been lost, the FUSE mission would be terminated.[1]
Optical design[עריכת קוד מקור | עריכה]
Although the original specification was to have a Wolter-type grazing incidence telescope,[2] the final design of the FUSE telescope comprises four individual mirrors. Each of the four mirrors is a 39-by-35 cm (15.4-by-13.8 in) off-axis parabola. Two mirror segments are coated with silicon carbide for reflectivity at the shortest ultraviolet wavelengths, and two mirror segments are coated with lithium fluoride over aluminum that reflects better at longer wavelengths. This optimizes performance over the entire spectral range.[3]
Each mirror has a corresponding astigmatism-corrected, holographically-ruled diffraction grating, each one on a curved substrate so as to produce four 1.65 m (5.4 ft) Rowland circle spectrographs. The dispersed ultraviolet light is detected by two microchannel plate intensified double delay-line detectors, whose surfaces are curved to match the curvature of the focal plane.[4]
Science results[עריכת קוד מקור | עריכה]
Over 400 scientific papers have been written using data from FUSE,[5] with subjects ranging from cool stars to the intergalactic medium. One of the primary science goals of FUSE was to study the abundance of deuterium, an isotope of hydrogen. Because of the large number of atomic absorption and emission lines in the far-ultraviolet, FUSE enabled many studies of galactic, extragalactic and intergalactic chemistry and chemical evolution.
References[עריכת קוד מקור | עריכה]
- ^ טקסט ההערה
- ^ Content, David A.; et al. (ביולי 1990). "Optical design of Lyman/FUSE". Instrumentation in Astronomy VII. 1235: pp. 943–952. doi:10.1117/12.19157.
{{cite journal}}: (עזרה);|pages=has extra text (עזרה); Explicit use of et al. in:|author2=(עזרה) - ^ טקסט ההערה
- ^ Sahnow, D.J.; et al. (1995-07-03). "The Far Ultraviolet Spectroscopic Explorer Mission". JHU.edu. נבדק ב-2007-09-07.
{{cite web}}: Explicit use of et al. in:|author2=(עזרה) - ^ "FUSE Publications". JHU.edu. נבדק ב-2007-09-07.
External links[עריכת קוד מקור | עריכה]
- FUSE website at Johns Hopkins University
- FUSE website at Institut d'Astrophysique de Paris
- FUSE archive at Multimission Archive at STScI (MAST)
FUSE was a NASA astrophysics satellite/telescope whose purpose was to explore the Universe using the technique of high-resolution spectroscopy in the far-ultraviolet spectral region. The Johns Hopkins University (JHU) had the lead role in developing the mission, in collaboration with The University of Colorado at Boulder, The University of California at Berkeley, international partners the Canadian Space Agency (CSA) and the French Space Agency (CNES), and numerous corporate partners. Professor Warren Moos of the Henry A. Rowland Department of Physics and Astronomy at JHU was the Principal Investigator. The FUSE satellite was launched on June 24, 1999, and operated until October 18, 2007.
FUSE Logo The mission was operated by a group of scientists and engineers from a control center in the Bloomberg Center for Physics and Astronomy building on JHU's Homewood campus in Baltimore, Maryland. The primary FUSE ground station was located at the Unversity of Puerto Rico Mayaguez. NASA/Goddard Space Flight Center provided management oversight of the project. As of 2009, FUSE was still the largest and most complex astrophysics mission that had been operated out of a university setting.
After its three-year primary mission, NASA extended FUSE operations several times to allow continued access to the far-ultraviolet spectral region by the astronomical community. Over the years, hundreds of astronomers from all over the world used FUSE to observe nearly 3000 different astronomical objects, totaling over 64 million seconds of successful observing time.
At the conclusion of the mission, the FUSE web presence was moved to its long term home at the Multi-mission Archive at Space Telescope (MAST), where the data archive is kept as well. Please visit this site for more information about the history of the FUSE project, the data from the mission, the photo archive, and much more: