Chapter Skim View of:

Currently Skimming:

Pages 10-36

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.

From page 10... ... Opportunities For Researcli Earth and Space Sciences Division Remote Sounding of Planetary Atmospheres D J McCleese 44 40 16 01 Spectral measurements of the mfrared radiation leaving a planetary atmosphere contain information on the composition, vertical temperature structure, and cloud morphology within This principle has been highly refined and successfully applied to the study of Earth's atmosphere from satellites At JPL, we are developing new infrared remote sensing instruments for the detailed study of the atmospheres of other planets from spacecraft This is accomplished by a program of theoretical modeling of radiauve transfer in planetary atmospheres and by the development and testing of instrumentation in the laboratory The current focal point is the design and implementation of an instrument for a future mission to Mars This instrument is intended to map the abundance and spatial distnbuuon of the water vapor in the Martian atmosphere, to determine the thermal structure of the atmosphere globally, and to map the airborne dust and condensates The measurement techniques employed include gas correlation spectroradiometry and filter radiometry Detailed Analysis of Planetary Atmospheric Structures G S Orton 44 40 16 02 Detailed models are being developed for atmospheric structures (including temperature, composition, and cloud properties) as a function of location on the planet and as a function of ume Emphasis IS placed on radiative transfer, both as a tool for determining atmospheric structure by passive remote sensing and as an agent in the establishment of energeuc (radiauve-convective) Read the entire page →
From page 11... ... spectroscopy, determining optical properties of candidate atmospheric constituents, and developing remote retrieval algorithms The program has emphasized analysis of the structures of thick planetary atmospheres, especially those of the outer planets and atmospheres with obscuring cloud and aerosol layers Recent emphasis is on analysis of Voyager reflected solar radiation and planetary thermal emission data to explore the atmospheres of Jupiter and Saturn Results of this work will be used in support of Galileo mission science and experiment planning for other, future planetary missions References G S Orton el al, Icarus 47, 145 (1981) G S Orton et al, Icarus 52, 94 (1982) Read the entire page →
From page 12... ... References T J Pacala e< a/, Appl Phys Lett -̂ -Z, 658 (1984) J B Laudenslager, in Excimer Lasers -- 1983, C K Rhodes et al, eds (AIP, New York, 1983) Read the entire page →
From page 13... ... program of high-resolution infrared observauons of the interstellar molecular gas is in its formative stage Collaborative investigations with other kinetics and observational groups and with members of the Caltech faculty are encouraged Electron-Photon-Atom Interactions S Trajmar 44 40 16 07 Electron collisions with laser-excited atoms (or molecules) are studied in crossed electron-photon-atom beam experiments A scanning, single-frequency, cw-dye laser is used for generating excited species for electron scattering measurements From these measurements, cross sections and orientation and alignment parameters are deduced Reference D F Register e< a/, Phys Rev Lett A28, 151 (1983) Read the entire page →
From page 14... ... completed A new technique has been developed to measure dissociative-attachment cross section from the vibrationally excited molecules Opportunities exist to do basic research in these fields with the aim of their application to planetary or stellar atmospheres References O J O n e n t & S K Snvastava.J Chem Phys 7* Read the entire page →
From page 15... ... provide direct integral data suitable for modeling high-electron temperature plasmas Reference A Chutjian, Phys Rev A 29, 64 (1984) Laboratory Interstellar Submillimeter and Microwave Spectroscopy Program R L Foynter E A Cohen H M Pickett 4440 16.13 Submillimeter and microwave spectra of both stable and transient atomic and molecular species are investigated in this laboratory research program The program's objecuve is to determine the spectroscopic parameters of such species with accuracies sufficient to predict their spectral lines from the microwave through the submillimeter region The spectral lines are employed by radio astronomers for the idenufication and interpretauon of their observational data Both known and likely interstellar molecules are invesugated Computer-controlled submillimeter and microwave spectrometers are available for this research Special absorption cells are used for the generauon and study of transient atomic and molecular species Stark, Zeeman, or source-modulation methods are employed as needed The 7-3000 GHz region is covered by various microwave, harmonicgeneration, and laser-sideband techniques This program provides direct support to the galactic and extragalactic radio astronomy program and maintains a close contact with the Theoretical Astrophysics, Interstellar Chemistry, Planetary Radio Astronomy, and Thermal Infrared Spectroscopy programs Reference J Farhoomand e« ai , J Appl Phys 57, 1763 (1985) Read the entire page →
From page 16... ... High-Energy Astrophysics: X-Ray Astronomy G R Riegler 44 40 16 15 Research in x-ray astronomy (0.1-10 keV) is being conducted with rocketborne and satellite instrumentaUon Studies of cosmic x-ray sources include analysis of data from instruments on the High Energy Astronomy Observatories HEAO-1 and HEAO-2 Instrumentation development is based on the use of charge-coupled devices (DDC's) Read the entire page →
From page 17... ... Solar-System Photometry and Imaging T V Johnson D L Matson 44 40 16 17 44 40 16 18 G J Veeder.Jr B A Goldberg This program consists of studies of planets, satellites, and comets through photometric observations and imaging over a wide spectral range of 0 3 M̂ jum to 3 Mjtm Equipment includes a Cassegrain scanner, a standard filter photometer, a special two-channel photometer allowing simultaneous visual and near infrared observations to be made, and the Silicon Imaging Photometer System (SIPS) , a silicon vidicon camera system which is capable of photometric imaging in a variety of modes over the spectral range 0 3 M\|xm to 1 1 Mjjim Observations can be made at JPL's Table Mountain Observatory, in addition, facilities at other observatories are available for observers with appropriate programs lo Studies D L Matson R W Carlson G J Veeder,Jr 44 40 16 19 T V Johnson D B Nash B A Goldberg lo, the innermost of the Galilean satelhtes of Jupiter, exhibits remarkable properties Active volcanoes are continually renewing its surface lo's morphology clearly shows that it has had a history of quite a different nature from those of other solar-system bodies Geologically it is at present the most active "planet " lo has the highest reflectivity of any object in the solar system, yet it shows none of the prominent absorption bands of frosts or hydrated minerals Furthermore, this satellite is surrounded by an extensive cloud of neutral sodium and other atoms, which emit at their characteristic atomic wavelengths Opportunities exist for collaborative work on (1) Read the entire page →
From page 18... ... lationships between asteroids, meteorites, and comets Opportunities exist in (1) nuclear track studies for determining preatmospheric sizes, spectra, and composition of heavy nuclei in ancient solar flares, (2) Read the entire page →
From page 19... ... physics and chemistry of minerals and rocks We have appked these methods of investigation to the Moon, Mars, the Galilean satellites of Jupiter, and the satellites of Saturn Work will be extended to other bodies as soon as the appropriate data become available Reference B A Smith et al, Science 215, 504 (1982) Radio Astronomy - Planetary S Gulkis MAJanssen M J Klein 44 40 16 23 The planetary radio astronomy group is actively pursuing a variety of theoretical and observational research programs whereby radio astronomical techniques are applied to current problems in solarsystem physics and astronomy Opportunities exist for participation in several ongoing programs that include spectroscopic and conunuum studies of (1) Read the entire page →
From page 20... ... anisotropy experiment on the Cosmic Background Explorer Satellite. Proposals combining some of these areas with observations are also welcome Asteroid Studies D L Matson T V Johnson S R Rajan 44 40 16 25 A W Harris G J Veeder,Jr A wealth of information about the composiuon of asteroid surfaces has become available as a result of recent observauonal theoretical work We are interested in the outstanding cosmochemical problems posed by the different types of asteroidal surface compositions and the resulting imphcations for the evolution of other solar-system objects Opportunities exist in (1) Read the entire page →
From page 21... ... characteristics of aerosol particles We are conducung theoretical modehng studies of radiative transfer in the atmospheres of the outer planets, as well as observation studies of limb darkening and spatial variations of molecular absorption features in their spectra References J T Bergstralh & J S Neff, Icarus 55, 40 (1983) J S Neff et al, Icarus 60, 221 (1984) Read the entire page →
From page 22... ... tones, and the possible role of impacts with regard to biological extinctions The emphasis in this program is on theoretical studies through computer modeling of the dynamical evolution of long- and short-period comets, using both integrated and Monte Carlo techniques, and computer modeling of the sublimation of volatiles on the surfaces of cometary nuclei Current areas of study include the ongin and evolution of the Oort cometary cloud, the role of planetary, stellar, and nongravitational perturbations in the evolution of cometary orbits, the flux and mass distribuuon of comets passing through the planetary region, and volatile and nonvolatile production rates for both known and hypothetical cometary nuclei. References P R Weissman, in Comets, L L Wilkening, ed (Univ of Arizona Press, Tucson, 1982) Read the entire page →
From page 23... ... Reference A E Metzgerrta/.J Geophys Res ««, 7731 (1983) Gravity-Wave Detection by Spacecraft Tracking H D Wahlquist F B Estabrook 44 40 16 33 The detecuon of V L F gravitational radiation by precision Doppler tracking of interplanetary spacecraft is being pursued The effect of gravity waves on the Doppler signal is known, and possible astrophysical sources for V L F gravitauonal radiation have been suggested Proposals have been accepted by NASA to conduct searches for gravity waves on interplanetary missions to be launched in the late 1980's Studies are now under way to determine the instrumental accuracy and frequency stability requirements, the noise interference problems resulung from propagauon of the Doppler signal through vanous media (interplanetary plasma, ionosphere, troposphere, etc ) Read the entire page →
From page 24... ... References B E Goldstein oi, J Geophys Res «6, 5485 (1981) MM Neugebauer« Read the entire page →
From page 25... ... References B T Tsurutani e< a/, J Geophys Res 57,6060(1982) B T Tsurutani & E J Smith, Geophys Res Lett 77, 331 (1984) Read the entire page →
From page 26... ... Atmospheric Sensing with Infrared Laser Techniques R T Menzies C.R Webster 44 40 16 42 The development o f tunable laser techniques fo r spectroscopy and remote measurement o f atmospheric gases is a continuing interest Laboratory spectral studies are conducted to supply data fo r use in remote-sensing applications Various laser spectroscopy techniques are used, including heterodyne, optogalvanic, and optoacoustic detection The current atmospheric measurement program includes the use o f tunable lead-salt diode lasers m a balloon-borne instrument f o r the simultaneous measurement o f the concentrations o f several stratospheric trace species that play important roles in stratospheric photochemistry The program also includes the development o f laser radar techniques f o r use in differential absorption or Doppler modes in order to measure gases, aerosols, and winds in the lower atmosphere Research opportunities are avialable in diode laser laboratory spectroscopy o f atmospheric species, lidar instrument development, held instrument data-acquisition and interpolation techniques, and the application o f new spectroscopic techniques fo r the sensitive detection o f gas-phase neutrals, radicals, and ions Infrared Atmospheric Remote Sensing/Laboratory Spectroscopy J S Margohs R A Toth L R Brown 44 40 16.43 Determination o f the concentrations o f minor gases at various altitudes in the Earth's atmosphere is o f considerable importance in meteorology, pollution, and photochemistry For such determinations, 0 01cm ' resolution interferometers are flown in ballons and the Space Shutde to record the atmospheric spectrum in the 2-to-16 j i m region These data are analyzed at the A T M OS (Atmospheric Trace Molecule) computing facility using a Prime minicomputer Interpretation o f such data requires accurate knowledge o f line positions, line strengths, and line widths o f d i f ferent vibrauon-rotation bands o f atmospheric molecules For this purpose, laboratory spectra are recorded with the 0 005-to-O 01 cm ' resolution interferometer at Kit t Peak National Observatory, with a 0 004-cm ' resolution Bomem interferometer at JPL, and a tunable diode laser facility at JPL Recent studies include analyses o f N2O, NO2, CH4, NH3, and H D O References L R Brown, et al, Appl Spectrosc 37, 287 (1983) Read the entire page →
From page 27... ... phere These applications blend into a broad program o f observational and theoretical investigations o f planetary atmospheres now being earned out by a variety o f means that include spacecraft programs as well as measurements made f o r ground-based observatories The program now in progress involves laboratory development o f electrooptic modulauon methods, specifically in the thermal I R and at high RF frequencies I n addition, there is interest i n radiative transfer in the Earth's upper atmosphere, particularly computations as applied to wind-sensing instruments References D J M c C l e e s e & J S Margolis, Appl Opt 22,2528 (1983) D J McCleese e< a / , Appl Opt 2 J , 527 (1984) Read the entire page →
From page 28... ... employed Flow discharge, photolysis, and pyrolysis cells are being used to generate transient molecules and ions Research opportunites exist in submillimeter spectroscopy and transient molecule generauon References E A C o h e n & H M Pickett.J Mol Spectrosc 97,97 (1983) E A Cohen e( a / . Read the entire page →
From page 29... ... waves in a number o f astrophysical environments m which enhanced density and temperature wi l l lead to a significant influence on chemistry I t has been conjectured that compression by shocks can trigger gravitational collapse and ultimately star formation Accordingly, we are also interested in studies o f chemical composition in shocked interstellar clouds with a view to using the predicted composition as diagnostics o f shocks This program is carried on in close concert wi th observational molecular radio astronomy, laboratory measurements o f lon-molecule reactions, and microwave spectroscopic measurements o f candidate interstellar species References S S Prasad & S P Tarafdar, Ap J 267, 603 (1983) S P Tarafdar et a / , AP J 289, 220 (1985) Read the entire page →
From page 30... ... keys, automatic data-processing procedures, and comparative analysis o f remotely sensed data in these two discipline areas References F K L I & M L Bryan, Photogramm Eng Remote Sensing 49, 791 (1983) M L Bryan, Internauonal Journal of Remote Sensing 4, 215 (1983) Read the entire page →
From page 31... ... Reference C Elachi et al, I E E E Trans Geos and Remote Sensing GE-22, 383 (1984) Mapping Arctic Landforms with Imaging Radar J P Ford 44 40 16.53 Experiments are being conducted to evaluate the effects o f diversities in radar-imaging parameters, e g , i l luminauon, polarizauon, and wavelength, on the mapping and geologic interpretauon o f landforms and surface processes in Arctic environments Airborne and spaceborne radar-image data sets are available f o r mapping glacial and periglacial landforms in Alaska and f o r interpreUng geomorphic processes, e g , floodplain and valley erosion, mass wasting, permafrost, effects o f transiuon f r o m freeze to thaw, etc Research includes digital data processing, evaluation o f synergism with optical/IR image data, and field verification in selected study areas Reference J P Ford, Quat Res (N Y ) Read the entire page →
From page 32... ... currendy being considered fo r use on fu ture operational meteorological satellites Challenging problems exist both in the design o f the instrumentation and the scienufic interpretation o f the measurements Research opportuniUes o f either a scientific or engineering nature are available R^erences R K Kakar, Journal of Climate and Appbed Meteorology 22, 1282 (1983) R K Kakar & B H Lambngtsen, Journal of Cbmate and Applied Meteorology 23, 1110(1984) Read the entire page →
From page 33... ... geobotany Init ial work was primarily with L A N D S A T data, but multispectral data f r o m many satellite and aircraft systems, spanning the spectrum f r o m visible through thermal inf rared to acUve and passive microwave, are now being utilized A t present, major emphasis IS being placed on imaging spectrometry I n addition to computer enhancement o f the remotely sensed data, the program involves a good deal o f field work with a variety o f specially devised sensors and laboratory work on samples brought back f r o m the field Primary interest in these studies is in using remotely sensed data in one or more o f the fol lowing areas economic geology, structural geology, mineralogy, geochemistry, and statistical and deterministic techniques o f data analysis References A F H Goetz & L C Rowan, Science 211, 781 (1981) A F H Goetz a / , Econ Geol 7* Read the entire page →
From page 34... ... (leaf anatomy and morphology) , chemical (pigment systems) Read the entire page →
From page 35... ... (7) To develop soil and rock classification systems based on spectral reflectance and thermal emittance data Infrared Astronomy on I R A S H H-G Aumann 44 40 16 63 The primary objective o f the In f ra red Astronomy Satellite (IRAS) Read the entire page →
From page 36... ... HOz, HO2NO2, HOCl , and HOSO2 TheoreUcal work on the interpretation o f the results is also being carried out The Physical Properties of Cometary Nuclei Z Sekanina 44 40 16 66 The goal o f this research is the understanding o f the physical nature o f a cometary nucleus Because o f the recognized diagnosuc properties o f the ejected dust, the investigation o f a broad range o f dust phenomena and their evolution in cometary atmospheres and tails is considered an integral part o f the nucleus studies The major objectives are (1) the nucleus structure and surface morphology, (2) Read the entire page →

From page 10...

... Opportunities For Researcli Earth and Space Sciences Division Remote Sounding of Planetary Atmospheres D J McCleese 44 40 16 01 Spectral measurements of the mfrared radiation leaving a planetary atmosphere contain information on the composition, vertical temperature structure, and cloud morphology within This principle has been highly refined and successfully applied to the study of Earth's atmosphere from satellites At JPL, we are developing new infrared remote sensing instruments for the detailed study of the atmospheres of other planets from spacecraft This is accomplished by a program of theoretical modeling of radiauve transfer in planetary atmospheres and by the development and testing of instrumentation in the laboratory The current focal point is the design and implementation of an instrument for a future mission to Mars This instrument is intended to map the abundance and spatial distnbuuon of the water vapor in the Martian atmosphere, to determine the thermal structure of the atmosphere globally, and to map the airborne dust and condensates The measurement techniques employed include gas correlation spectroradiometry and filter radiometry Detailed Analysis of Planetary Atmospheric Structures G S Orton 44 40 16 02 Detailed models are being developed for atmospheric structures (including temperature, composition, and cloud properties) as a function of location on the planet and as a function of ume Emphasis IS placed on radiative transfer, both as a tool for determining atmospheric structure by passive remote sensing and as an agent in the establishment of energeuc (radiauve-convective)