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The 1980 solar maximum mission event listing

Information is contained on solar burst and transient activity observed by the Solar Maximum Mission (SMM) during 1980 pointed observations. Data from the following SMM experiments are included: (1) Gamma Ray Spectrometer, (2) Hard X-Ray Burst Spectrometer, (3) Hard X-Ray Imaging Spectrometer, (4) Flat Crystal Spectrometer, (5) Bent Crystal Spectrometer, (6) Ultraviolet Spectrometer and Polarimeter, and (7) Coronagraph/Polarimeter. Correlative optical, radio, and Geostationary Operational Environmental Satellite (GOES) x ray data are also presented. Where possible, bursts or transients observed in the various wavelengths were grouped into discrete flare events identified by unique event numbers. Each event carries a qualifier denoting the quality or completeness of the observations. Spacecraft pointing coordinates and flare site angular displacement values from Sun center are also included.

Speich, D. M.↗

The 1988 Solar Maximum Mission event list

Information on solar burst and transient activity observed by the Solar Maximum Mission (SMM) during 1988 pointed observations is presented. Data from the following SMM experiments are included: (1) gamma ray spectrometer; (2) hard x ray burst spectrometer; (3) flat crystal spectrometers; (4) bent crystal spectrometer; (5) ultraviolet spectrometer polarimeter; and (6) coronagraph/polarimeter. Correlative optical, radio, and Geostationary Operational Environmental Satellite (GOES) x ray data are also presented. Where possible, bursts, or transients observed in the various wavelengths were grouped into discrete flare events identified by unique event numbers. Each event carries a qualifier denoting the quality or completeness of the observation. Spacecraft pointing coordinates and flare site angular displacement values from sun center are also included.

Dennis, B. R.↗

The 1984 - 1987 Solar Maximum Mission event list

Information on solar burst and transient activity observed by the Solar Maximum Mission (SMM) during 1984-1987 pointed observations is presented. Data from the following SMM experiments are included: (1) gamma ray spectrometer; (2) hard x-ray burst spectrometer; (3) flat crystal spectrometer; (4) bent crystal spectrometer; (5) ultraviolet spectrometer polarimeter; and (6) coronograph/polarimeter. Correlative optical, radio, and Geostationary Operational Environmental Satellite (GOES) x ray data are also presented. Where possible, bursts or transients observed in the various wavelengths were grouped into discrete flare events identified by unique event numbers. Each event carries a qualifier denoting the quality or completeness of the observations. Spacecraft pointing coordinates and flare site angular displacement values from sun center are also included.

Dennis, B. R.↗

The 1989 Solar Maximum Mission event list

This document contains information on solar burst and transient activity observed by the Solar Maximum Mission (SMM) during 1989 pointed observations. Data from the following SMM experiments are included: (1) Gamma Ray Spectrometer, (2) Hard X-Ray Burst Spectrometer, (3) Flat Crystal Spectrometer, (4) Bent Crystal Spectrometer, (5) Ultraviolet Spectrometer Polarimeter, and (6) Coronagraph/Polarimeter. Correlative optical, radio, and Geostationary Operational Satellite (GOES) X-ray data are also presented. Where possible, bursts or transients observed in the various wavelengths were grouped into discrete flare events identified by unique event numbers. Each event carries a qualifier denoting the quality or completeness of the observations. Spacecraft pointing coordinates and flare site angular displacement values from sun center are also included.

Dennis, B. R.↗

Galileo Orbiter Ultraviolet Observations of Jupiter Aurora

In 1996 during the first four orbits of the satellite tour the Galileo ultraviolet spectrometer (UVS) (1130-4320 A) and extreme ultraviolet spectrometer (EUVS)(540-1280 A) performed near-simultaneous observations of the Jupiter aurora in both the north and south polar regions.

satellite↗

Design of a mirror pointing and occulting mechanism for the Ultraviolet Coronagraph Spectrometer (UVCS)

The Mirror and Occulter Mechanism (MOM), a lightweight stable optical assembly which is a critical component to the Ultraviolet Coronagraph Spectrometer to be flown on the European SOHO spacecraft, is discussed. The MOM combines the functions of precision mirror pointing and occultation of stray light into a single package. The mirror mechanism and occulter mechanism designs are described and development testing and life testing activities are discussed.

Highman, Clifton O.↗

Determining the operating characteristics of an ultraviolet interferometric spectrometer

A prototype interferometric spectrometer system is being built by NASA to explore the potential of the technique for applications involving the visible and near ultraviolet portions of the electromagnetic spectrum. The system is limited only by the frequency bandpass of the optical components used in the system, the quality of the optical components, and ultimately by the memory capacity of the computer; tradeoffs between the wavenumber resolution of the produced spectrum, the bandpass limits of the optics, and the number of samples obtained from the interferogram must be delineated explicitly. The prototype Ultraviolet Interferometric Spectrometer (UVIS) instrument is expected to be configured several different ways to ascertain its suitability for various applications. To exploit its inherent flexibility, this reference document describes these parameter tradeoffs.

Parsons, C. L.↗

Extreme ultraviolet imaging spectrometer for thermospheric emissions

One of the instruments that has been developed to fly on the Space Shuttle is the Imaging Spectrometric Observatory, an array of five imaging spectrometers to cover the 300-12,000-A wavelength range. In this paper the spectrometer designed to operate in the extreme ultraviolet is described. The instrument is intended for studies of the thermosphere and magnetosphere and support of various plasma experiments to be performed from the Shuttle. The design is modular so that various components such as gratings and detectors can be changed and optimized for a range of specific studies following the first survey mission. The detector is an intensified 2-D CCD which permits simultaneous spectral and spatial imaging. The spectral multiplexing gives the spectrometer a considerable speed advantage. The instrument has a small field of view and is thus capable of obtaining much needed scale height information on the atmospheric EUV emissions. Operating from the Shuttle, global and temporal coverage will be obtained, and the EUV data will be enhanced by the simultaneously acquired UV, visible, and near-IR observations.

Torr, M. R.↗

Study of an astronomical extreme ultraviolet rocket spectrometer for use on shuttle missions

The adaptation of an extreme ultraviolet astronomy rocket payload for flight on the shuttle was studied. A sample payload for determining integration and flight procedures for experiments which may typically be flown on shuttle missions was provided. The electrical, mechanical, thermal, and operational interface requirements between the payload and the orbiter were examined. Of particular concern was establishing a baseline payload accommodation which utilizes proven common hardware for electrical, data, command, and possibly real time monitoring functions. The instrument integration and checkout procedures necessary to assure satisfactory in-orbit instrument performance were defined and those procedures which can be implemented in such a way as to minimize their impact on orbiter integration schedules were identified.

Bowyer, C. S.↗

The Coronal Ultraviolet Berkeley Spectrometer (CUBS)

We describe an instrument package to remotely measure thermospheric, exospheric, and plasmaspheric structure and composition. This instrument was flown aboard the second test flight of the Black Brant XII sounding rocket on December 5, 1989, which attained an apogee of 1460 km. The experiment package consisted of a spectrophotometer to measure He I 584 A, O II 834 A, O I 989 A, hydrogen Lyman beta (1025 A), hydrogen Lyman alpha (1216 A), and O I 1304 A transitions, and a photometer to measure the He II 304 A emission. The optical design of the spectrophotometer was identical to that of the Berkeley Extreme Ultraviolet (EUV) Airglow Rocket Spectrometer payload, flown on September 30, 1988 aboard the maiden flight of the Black Brant XII rocket. We present the initial data analysis and describe directions we will go toward the completion of our study.

Bush, Brett C.↗

End-to-End System Test and Optical Performance Evaluation for the Solar and Heliosphere Observatory (SOHO) Ultraviolet Coronagraph Spectrometer (UVCS)

The UVCS is one of the instruments carried by the Solar and Heliospheric Observatory (SOHO), a joint NASA/ESA Spacecraft launched in November 1995. It is designed to perform ultraviolet spectroscopy and visible light polarimetry of the extended solar corona. The primary scientific objectives of the UVCS investigation are to study the physical processes occurring in the extended solar corona, such as: the mechanism of acceleration of the solar wind, the mechanism of coronal plasma heating, the identification of solar wind sources, and the investigation of the plasma properties of the solar wind. The UVCS End-to-End test activities included a comprehensive set of system level functional and optical tests. Although performed under severe schedule constraints, the End-to-End System Test was very successful and served to fully validate the UVCS optical design. All test results showed that the primary scientific objectives of the UVCS Mission were achievable.

Carosso, Paolo A.↗

Doppler line profiles measurement of the Jovian Lyman Alpha emission with OAO-C

Observation of Jupiter made with the high resolution ultraviolet spectrometer of the Orbiting Astronomical Observatory copernicus in April and May, 1980, yield a Jovian Lyman alpha emission intensity of 7 + or 2.5 RR. This indicates a decrease by about a factor of two since the Voyager ultraviolet spectrometer measurements, nearly a year earlier. An unusually high column abundance of hydrogen atoms above the methane homopause at the Voyager epoch is indicated. Since the auroral charged particle bombardment of molecular hydrogen is expected to contribute significantly to the global population of the hydrogen atoms, it is suggested that at the time of the Voyager Jupiter encounter unusually high auroral activity existed, perhaps d to the high concentration of the Io plasma torus. The temporal variation of the Saturn lyman alpha emission, when contrasted with the Jovian data, reveals that the auroral processes are not nearly as important in determining the Saturn Lyman alpha intensity in the nonauroral region.

Barker, E. S.↗

Chemical Analysis of Primitive Objects Using a Slitless Ultraviolet Meteor Spectrometer (CAPO-SUMS)

Measure the elemental composition in both random meteors and in the bolides forming specific meteor streams (these are traceable to specific small bodies in the solar system). These will yield the average chemical composition and degree of chemical variability in a statistically significant number of planetesimals. CAPO-SUMS is functionally equivalent to a series of multiple, small-body sample analysis missions, but provides much more analytical capability than is possible on any orbital or flyby mission due to the vaporization, ionization and ultraviolet emission from the ablating bolide as it enters the atmosphere. CAPO-SUMS will provide a chemical context from which the detailed analytical studies provided by a cometary or asteroidal lander mission can be interpreted.

Nuth, J. A.↗

SOHO Ultraviolet Coronagraph Spectrometer (UVCS) Mission Operations and Data Analysis

The scientific goal of UVCS is to obtain detailed empirical descriptions of the extended solar corona as it evolves from a period of minimum activity to maximum and to use these descriptions to identify and understand the physical processes responsible for coronal heating, solar wind acceleration, coronal mass ejections (CME's), and the phenomena that establish the plasma properties of the solar wind as measured by the CELIAS/SOHO experiment. We must observe a wide range of conditions (e.g., heating rate, impulsive mass ejections, magnetic field opening) in order to choose among competing theoretical explanations of the observed coronal structures and dynamics. During the first year of scientific observations (1 April 1996 through 31 March 1997), the LTVCS made the first extensive ultraviolet spectroscopic observations above the base of the solar corona. Those observations revealed extremely high most probable speeds along the line of sight for O(5+) in polar coronal holes above 2 solar radii from sun center and smaller such speeds for H(0) and protons. Doppler dimming and pumping diagnostics indicated that O(5+) and H(0) I reached supersonic outflow velocities within 2 solar radii. The observations appeared to be consistent with O95+) heating and direct momentum transfer by high frequency MHD waves through ion cyclotron resonance. Equatorial streamers were found to appear much different when observed in O VI, Fe XII and Mg X than when observed in H I Lyman-alpha or visible light. This led G. Noci to suggest that the elemental abundance of O, Fe, and Mg are lower in the dark center region of the O VI streamer image than it is in the brighter outer legs of the streamer. The O VI line ratio indicated a much smaller outflow speed in streamers than in the surrounding coronal holes. Spectroscopic observations of CME's in June and December 1996 showed large Doppler shifts indicating macroscopic flows of up to 200 km/s transverse to the apparent motion of the CME. The December event displayed factor of 500 intensity increases in H I Lyman lines and bright emissions in cool ion lines like C III 977 A indicating that the origin of some of the gas was a prominence. UVCS also observed two comets, several stars and interplanetary hydrogen. In the current reporting period, the initial results were published and detailed analyses including self consistent empirical models were developed. The research results were reported, published or submitted/accepted for publication. New observations were made to uncover additional information about the surprising results of the first year and other new observations revealed more surprises. A UVCS Tutorial was developed to familiarize potential users of UVCS data with the data products, analysis techniques and coronal models needed to analyze the data.

Kohl, John L.↗