The Special Sensor Ultraviolet Limb Imager (SSULI) is an imaging spectrometer that is used to observe the earth's ionosphere and thermosphere. These sensors provide vertical intensity profiles of airglow emissions in the extreme ultraviolet and far ultraviolet spectral range of 800 to 1700 Angstrom (80 to 170 nanometre) and scan from 75 km to 750 km tangent altitude. The data from these sensors will be used to infer altitude profiles of ion, electron and neutral density.[1]
SSULI Components
The Naval Research Laboratory (NRL) developed five ultraviolet remote sensing instruments for the Air Force Defense Meteorological Satellite Program (DMSP). These instruments known as SSULI (Special Sensor Ultraviolet Limb Imager) launched aboard the DMSP block of 5D3 satellites, which started in 2003. SSULI measures vertical profiles of the natural airglow radiation from atoms, molecules and ions in the upper atmosphere and ionosphere by viewing the Earth's limb at a tangent altitude of approximately 50 km to 750 km.[2]
The last SSULI is at NRL awaiting a new "ride" due to the cancellation[3] and preservation of the last DMSP satellite.[4]
Mission detailsedit
Measurements are made from the extreme ultraviolet (EUV) to the far ultraviolet (FUV) over the wavelength range of 80 nanometers to 170 nanometers, with 1.8 nanometer resolution. The satellites will be launched in a near-polar, Sun-synchronous orbit at an altitude of approximately 830 km. The Low Resolution Airglow and Auroral Spectrograph (LORAAS), a SSULI prototype, was launched on board the Advanced Research and Global Observation Satellite (ARGOS_(satellite)) on February 23, 1999. LORAAS data was used to validate SSULI algorithms that convert raw measurements (Figure 2) into useful environmental parameters that characterize the upper atmosphere.[2]
Softwareedit
An extensive operational data processing system has been developed to generate environmental data from SSULI spectral data. Spectral data from the LORAAS instrument is also part of this platform. This system, known as the Ground Data Analysis Software (GDAS), includes operational data reduction software using advanced science algorithms also developed at NRL, a customized graphical user interface (GUI), and comprehensive validation techniques. Programs are designed to generate a SSULI Prep file from multiple data sources including Raw Sensor Data Records (RSDR) at the Air Force Weather Agency (AFWA), HIRAAS real-time data assembled at US Space Command, and an extensive HIRAAS infobase on site at the Naval Research Laboratory.[2]
Technical informationedit
The sensor has a field-of-view of 2.4°x0.15° and sweeps out a 2.4°x17° field-of-regard during each 90 second scan, with wavelength coverage between 800Å and 1700Å at 23Å resolution. The field of view scans ahead of the spacecraft in the orbital plane through a 17° field of regard, corresponding to approximately 75–750 km altitude.
Referencesedit
^ abc Milazzo, Anna-Clair; Thonnard, Stefan E.; Lam, Chau (1998). "Performance measurements and results of the SSULI (Special Sensor Ultraviolet Limb Imager) stacked-grid collimator". X-Ray and Ultraviolet Spectroscopy and Polarimetry II. Proceedings of SPIE. Vol. 3443. pp. 7–18. doi:10.1117/12.333615. ISBN9780819428981. S2CID 120312927.
^ abcThis article contains public domain material from the United States Navy. See the below citation for the source:
"SSULI (Special Sensor Ultraviolet Limb Imager)". U.S. Naval Research Laboratory. Retrieved 2012-07-27.[permanent dead link]
^Clark, Stephen (30 March 2016). "Air Force ends effort to recover DMSP weather satellite". Spaceflight Now. Retrieved 21 March 2018.
^"Air Force Secretary unveils final DMSP satellite at SMC". Spaceflight Now. 14 December 2017. Retrieved 24 March 2018.
External linksedit
November 10, 2023
special, sensor, ultraviolet, limb, imager, ssuli, imaging, spectrometer, that, used, observe, earth, ionosphere, thermosphere, these, sensors, provide, vertical, intensity, profiles, airglow, emissions, extreme, ultraviolet, ultraviolet, spectral, range, 1700. The Special Sensor Ultraviolet Limb Imager SSULI is an imaging spectrometer that is used to observe the earth s ionosphere and thermosphere These sensors provide vertical intensity profiles of airglow emissions in the extreme ultraviolet and far ultraviolet spectral range of 800 to 1700 Angstrom 80 to 170 nanometre and scan from 75 km to 750 km tangent altitude The data from these sensors will be used to infer altitude profiles of ion electron and neutral density 1 SSULI ComponentsThe Naval Research Laboratory NRL developed five ultraviolet remote sensing instruments for the Air Force Defense Meteorological Satellite Program DMSP These instruments known as SSULI Special Sensor Ultraviolet Limb Imager launched aboard the DMSP block of 5D3 satellites which started in 2003 SSULI measures vertical profiles of the natural airglow radiation from atoms molecules and ions in the upper atmosphere and ionosphere by viewing the Earth s limb at a tangent altitude of approximately 50 km to 750 km 2 Contents 1 Overview 2 Launch 3 Mission details 4 Software 5 Technical information 6 References 7 External linksOverview editThe United States Naval Research Laboratory NRL built five of these ultraviolet spectrographs for the United States Air Force USAF Defense Meteorological Satellite Program DMSP block of 5D3 satellites 1 Launch editThe first sensor was launched on the DMSP F16 spacecraft in October 2003 into a Sun synchronous 830 km circular orbit at a local time of 0800 2000 UT 1 Three of the remaining four SSULIs were launched on the following DMSP Block 5D3 satellitesDefense Meteorological Satellite Program Block 5D DMSP F17 November 4 2006 DMSP F18 October 18 2009 DMSP F19 April 3 2014The last SSULI is at NRL awaiting a new ride due to the cancellation 3 and preservation of the last DMSP satellite 4 Mission details editMeasurements are made from the extreme ultraviolet EUV to the far ultraviolet FUV over the wavelength range of 80 nanometers to 170 nanometers with 1 8 nanometer resolution The satellites will be launched in a near polar Sun synchronous orbit at an altitude of approximately 830 km The Low Resolution Airglow and Auroral Spectrograph LORAAS a SSULI prototype was launched on board the Advanced Research and Global Observation Satellite ARGOS satellite on February 23 1999 LORAAS data was used to validate SSULI algorithms that convert raw measurements Figure 2 into useful environmental parameters that characterize the upper atmosphere 2 Software editAn extensive operational data processing system has been developed to generate environmental data from SSULI spectral data Spectral data from the LORAAS instrument is also part of this platform This system known as the Ground Data Analysis Software GDAS includes operational data reduction software using advanced science algorithms also developed at NRL a customized graphical user interface GUI and comprehensive validation techniques Programs are designed to generate a SSULI Prep file from multiple data sources including Raw Sensor Data Records RSDR at the Air Force Weather Agency AFWA HIRAAS real time data assembled at US Space Command and an extensive HIRAAS infobase on site at the Naval Research Laboratory 2 Technical information editThe sensor has a field of view of 2 4 x0 15 and sweeps out a 2 4 x17 field of regard during each 90 second scan with wavelength coverage between 800A and 1700A at 23A resolution The field of view scans ahead of the spacecraft in the orbital plane through a 17 field of regard corresponding to approximately 75 750 km altitude References edit a b c Milazzo Anna Clair Thonnard Stefan E Lam Chau 1998 Performance measurements and results of the SSULI Special Sensor Ultraviolet Limb Imager stacked grid collimator X Ray and Ultraviolet Spectroscopy and Polarimetry II Proceedings of SPIE Vol 3443 pp 7 18 doi 10 1117 12 333615 ISBN 9780819428981 S2CID 120312927 a b c This article contains public domain material from the United States Navy See the below citation for the source SSULI Special Sensor Ultraviolet Limb Imager U S Naval Research Laboratory Retrieved 2012 07 27 permanent dead link Clark Stephen 30 March 2016 Air Force ends effort to recover DMSP weather satellite Spaceflight Now Retrieved 21 March 2018 Air Force Secretary unveils final DMSP satellite at SMC Spaceflight Now 14 December 2017 Retrieved 24 March 2018 External links editSpecial Sensor Ultraviolet Limb Imager Retrieved from https en wikipedia org w index php title Special Sensor Ultraviolet Limb Imager amp oldid 1176712197, wikipedia, wiki, book, books, library,
