Issue 10 Volume 41 May 16, 2003

20030038794 Lawrence Livermore National Lab., Livermore, CA
Portent of Heine’s Reciprocal Square Root Identity
Cohl, H. S.; Oct. 12, 2002; 12 pp.
Report No.(s): DE2002-15002149; UCRL-JC-150467; No Copyright; Avail: Department of Energy Information Bridge
Precise efforts in theoretical astrophysics are needed to fully understand the mechanisms that govern the structure,
stability, dynamics, formation, and evolution of differentially rotating stars. Direct computation of the physical attributes of
a star can be facilitated by the use of highly compact azimuthal and separation angle Fourier formulations of the Green’s
functions for the linear partial differential equations of mathematical physics.
NTIS
Star Formation; Boundary Value Problems
91
LUNAR AND PLANETARY SCIENCE AND EXPLORATION
Includes planetology; selenology; meteorites; comets; and manned and unmanned planetary and lunar flights. For spacecraft design or
space stations see 18 Spacecraft Design, Testing and Performance.
20030032439 NASA Ames Research Center, Moffett Field, CA, USA
Evaluation of Human vs. Teleoperated Robotic Performance in Field Geology Tasks at a Mars Analog Site
Glass, B.; Briggs, G.; [2003]; 8 pp.; In English; 7th International Symposium on Artificial Intelligence, Robotics and
Automation in Space (i-SAIRAS 2003), 1-23 May 2003, Nara, Japan; Original contains black and white illustrations; No
Copyright; Avail: CASI; A02, Hardcopy
Exploration mission designers and planners have costing models used to assess the affordability of given missions - but
very little data exists on the relative science return produced by different ways of exploring a given region. Doing cost-benefit
analyses for future missions requires a way to compare the relative field science productivity of spacesuited humans vs. virtual
presence/teleoperation from a nearby habitat or orbital station, vs. traditional terrestrial-controlled rover operations. The goal
of this study was to define science-return metrics for comparing human and robotic fieldwork, and then obtain quantifiable
science-return performance comparisons between teleoperated rovers and spacesuited humans. Test runs with a simulated
2015-class rover and with spacesuited geologists were conducted at Haughton Crater in the Canadian Arctic in July 2002.
Early results imply that humans will be 1-2 orders of magnitude more productive per unit time in exploration than future
terrestrially-controlled robots.
Author
Mars Exploration; Planetary Geology; Robotics; Mars Surface; Manned Space Flight
20030032942 NASA Goddard Space Flight Center, Greenbelt, MD, USA
Production, Outflow Velocity, and Radial Distribution of H2O and OH in the Coma of Comet C/1995 O1 [Hale-Bopp]
from Wide Field Imaging of OH
Harris, Walter M.; Scherb, Frank; Mierkiewicz, Edwin; Oliverson, Ronald; Morgenthaler, Jeffrey; [2003]; 2 pp.; In English;
Copyright; Avail: Other Sources; Abstract Only
Observations of OH are a useful proxy of the water production rate (Q(sub H2O)) and outflow velocity (V(sub out)) in
comets. From wide field images taken on 03/28/1997 and 04/08/1997 that capture the entire scale length of the OH coma of
comet C/1995 O1 (Hale-Bopp), we obtain Q(sub H2O) from the model-independent method of aperture summation. With an
adaptive ring summation algorithm, we extract the radial brightness distribution of OH 0-0 band emission out to cometocentric
distances of up to 10(exp 6) km, both as azimuthal averages and in quadrants covering different position angles relative to the
comet-Sun line. These profiles are fit using both fixed and variable velocity 2-component spherical expansion models to
estimate V(sub OH) with increasing distance from the nucleus. The OH coma of Hale-Bopp was more spatially extended than
previous comets, and this extension is best matched by a variable acceleration of H2O and OH that acted across the entire
coma, but was strongest within 1-2 x 10(exp 4) km from the nucleus. Our models indicate that V(sub OH) at the edge of our
detectable field of view (10(exp 6) km) was approx. 2-3 times greater in Hale-Bopp than for a 1P/Halley-class comet at 1 AU,
which is consistent with the results of more sophisticated gas-kinetic models, extrapolation from previous observations of OH
in comets with Q(sub H2O) greater than 10(exp 29)/s , and direct radio measurements of the outer coma Hale-Bopp OH
velocity. The most probable source of this acceleration is thermalization of the excess energy of dissociation of H2O and OH
over an extended collisional coma. When the coma is broken down by quadrants in position angle, we find an azimuthal
asymmetry in the radial distribution that is characterized by an increase in the spatial extent of OH in the region between the
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