H. A. Weaver
A5024139161- Astro and Planetary Science
- Planetary Science and Exploration
- Isotope Analysis in Ecology
- Stellar, planetary, and galactic studies
- Space Exploration and Technology
- Atmospheric Ozone and Climate
- Solar and Space Plasma Dynamics
- Astrophysics and Star Formation Studies
- Geology and Paleoclimatology Research
- Gamma-ray bursts and supernovae
- Nuclear Physics and Applications
- Astronomy and Astrophysical Research
- Spacecraft and Cryogenic Technologies
- Geological and Geochemical Analysis
- Geomagnetism and Paleomagnetism Studies
- Astronomical Observations and Instrumentation
- Ionosphere and magnetosphere dynamics
- Nuclear physics research studies
- Space Satellite Systems and Control
- Mass Spectrometry Techniques and Applications
- Astronomical and nuclear sciences
- Spectroscopy and Laser Applications
- Geophysics and Gravity Measurements
- High-pressure geophysics and materials
- Methane Hydrates and Related Phenomena
Johns Hopkins University Applied Physics Laboratory
2016-2025
Mid Essex Hospital Services NHS Trust
2024
Johns Hopkins University
2007-2022
Allentown Public Library
2010-2021
University of Virginia
2019
Ames Research Center
2007-2018
Bloomberg (United States)
2001-2018
Southwest Research Institute
2007-2016
Goddard Space Flight Center
1982-2007
Academy of Athens
2007
The Far Ultraviolet Spectroscopic Explorer satellite observes light in the far-ultraviolet spectral region, 905-1187 Å, with a high resolution. instrument consists of four co-aligned prime-focus telescopes and Rowland spectrographs microchannel plate detectors. Two telescope channels use Al : LiF coatings for optimum reflectivity between approximately 1000 1187 other two SiC optimized throughput 905 1105 Å. gratings are holographically ruled to correct largely astigmatism minimize scattered...
New Horizons' views of Pluto The flyby and its moon Charon by the Horizons spacecraft generated news coverage around world. Now Stern et al. report first scientific results from high-speed encounter. surface is surprisingly diverse, with large regions differing brightness composition. There ample evidence for ongoing rich geological processes that act to sculpt surface. Charon's similarly complex, numerous relief structures varied coloration. Pluto's atmosphere extensive but less dense than...
The launch of the Far Ultraviolet Spectroscopic Explorer (FUSE) has been followed by an extensive period calibration and characterization as part preparation for normal satellite operations. Major tasks carried out during this include initial coalignment, focusing, four instrument channels a preliminary measurement resolution throughput performance instrument. We describe results from test program present estimates on-orbit FUSE based on combination these data prelaunch laboratory measurements.
The New Horizons spacecraft mapped colors and infrared spectra across the encounter hemispheres of Pluto Charon. volatile ices CH$_4$, CO, N$_2$, that dominate Pluto's surface, have complicated spatial distributions resulting from sublimation, condensation, glacial flow acting over seasonal geological timescales. H$_2$O ice "bedrock" is also mapped, with isolated outcrops occurring in a variety settings. surface exhibits complex regional color diversity associated its distinct provinces....
New Horizons unveils the Pluto system In July 2015, spacecraft flew through at high speed, humanity's first close look this enigmatic on outskirts of our solar system. a series papers, team present their analysis encounter data downloaded so far: Moore et al. complex surface features and geology its large moon Charon, including evidence tectonics, glacial flow, possible cryovolcanoes. Grundy analyzed colors chemical compositions surfaces, with ices H 2 O, CH 4 , CO, N NH 3 reddish material...
New Horizons unveils the Pluto system In July 2015, spacecraft flew through at high speed, humanity's first close look this enigmatic on outskirts of our solar system. a series papers, team present their analysis encounter data downloaded so far: Moore et al. complex surface features and geology its large moon Charon, including evidence tectonics, glacial flow, possible cryovolcanoes. Grundy analyzed colors chemical compositions surfaces, with ices H 2 O, CH 4 , CO, N NH 3 reddish material...
Some active asteroids have been proposed to be formed as a result of impact events1. Because are generally discovered by chance only after their tails fully formed, the process how ejecta evolve into tail has, our knowledge, not directly observed. The Double Asteroid Redirection Test (DART) mission NASA2, in addition having successfully changed orbital period Dimorphos3, demonstrated activation an asteroid resulting from under precisely known conditions. Here we report observations DART with...
The Kuiper Belt is a distant region of the Solar System. On 1 January 2019, New Horizons spacecraft flew close to (486958) 2014 MU69, Cold Classical Object, class objects that have never been heated by Sun and are therefore well preserved since their formation. Here we describe initial results from these encounter observations. MU69 bi-lobed contact binary with flattened shape, discrete geological units, noticeable albedo heterogeneity. However, there little surface color compositional No...
Impact craters on Pluto and Charon Collisions between Solar System bodies produce impact large objects at a rate that depends the population of impacting small bodies. Singer et al. examined its moon Charon. Some regions have had their erased by recent geological processes, but others appear to record 4 billion years impacts. Because are located in Kuiper belt, distribution crater sizes reflects size belt (KBOs). The authors found fewer KBOs than predicted models collision equilibrium,...