Results 81 to 90 of about 18,971,872 (256)

Nineteenth century astronomy at the US Naval Academy [PDF]

open access: yes, 2002
During the 1850s the newly-formed U.S. Naval Academy in Annapolis, Maryland, acquired a small observatory featuring a 19.7-cm (7.75-in.) Clark refractor, transit telescopes, and an astronomical clock.
Shankland, Paul D., Orchiston, Wayne
core   +1 more source

924 elementary problems and answers in solar system astronomy

open access: yes, 1993
This challenging collection of problems is organized into seven carefully crafted, thoughtful chapters on the Sun and the nature of the solar system; the motion of the planets; the Sun, Earth, and Moon; the sky as observed from the rotating, revolving ...
Van Allen, James A
core  

Post‐flight assessment of the OSIRIS‐REx Sample Return Capsule (SRC) for organic and other potential contaminants

open access: yesMeteoritics &Planetary Science, EarlyView.
Abstract Regolith samples from the carbonaceous asteroid Bennu were stowed and delivered to Earth in the OSIRIS‐REx spacecraft's Sample Return Capsule (SRC). We applied multiple analytical techniques to study the components of the post‐flight SRC, with a focus on assessing the conditions and any contaminants to which the Bennu samples were exposed ...
Scott A. Sandford   +35 more
wiley   +1 more source

The history of astronomy: a very short introduction

open access: yes, 2003
The History of Astronomy: A Very Short Introduction traces the history of Western astronomy, from prehistoric times to the origins of astrophysics in the mid-nineteenth century and the technical developments since the Second World War. Astronomy, perhaps
Hoskin, Michael
core   +1 more source

Xenoliths in meteorites: Insights into the dynamics of material exchange between asteroids

open access: yesMeteoritics &Planetary Science, EarlyView.
Abstract A minor fraction of meteorites contains xenoliths, that is, clasts that were formed on a different parent body than that of the host lithology. The occurrence of xenoliths is direct evidence for the exchange of material between asteroids, including exchanges between asteroids from the carbonaceous (CC) and non‐carbonaceous (NC) reservoirs ...
J. Gattacceca   +17 more
wiley   +1 more source

Solar Wind—Ionosphere Interface at Mars. Ion Dynamics, Asymmetry, Plasma Jets

open access: yesGeophysical Research Letters
We report on observations made by the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft, in the shocked solar wind‐ionosphere interface of Mars. We observe a strong asymmetry in plasma flow governed by the direction of the motional electric field.
E. Dubinin   +6 more
doaj   +1 more source

Water and hydroxyl on asteroid Bennu: Reconciling remote observations with OSIRIS‐REx sample analysis

open access: yesMeteoritics &Planetary Science, EarlyView.
Abstract This study investigates the spatial distribution and spectral characteristics of the broad hydration feature near 3 μm across the surface of asteroid (101955) Bennu using OVIRS (OSIRIS‐REx Visible and InfraRed Spectrometer) data. We analyzed multiple global OVIRS data sets obtained at different times throughout the Bennu day, revealing ...
Hannah H. Kaplan   +5 more
wiley   +1 more source

Have Astronauts Visited Neptune? Student Ideas About How Scientists Study The Solar System [PDF]

open access: yes, 2017
The nature of students’ ideas about the scientific practices used by astronomers when studying objects in our Solar System is of widespread interest to discipline-based astronomy education researchers.
KeriAnn Rubin   +19 more
core   +1 more source

Thermal history, collisional history, and structure of the CK‐chondrite parent body

open access: yesMeteoritics &Planetary Science, EarlyView.
Abstract Major chondrite groups (H, L, LL, R, EH, EL, CK) with some members of petrologic type 5 and 6 also have some members of types 3 and 4; they do not have members of type 1 or 2. Their parent bodies had onion‐shell structures and were internally heated by the decay of 26Al.
Alan E. Rubin
wiley   +1 more source

New Polarimetric Data for the Galilean Satellites: Io and Ganymede Observations and Modeling

open access: yesThe Planetary Science Journal
New high-precision disk-integrated measurements of the polarization of Io and Ganymede in the UBVRI bands are presented. The observations were obtained using polarimeters mounted on the Crimean Astrophysical Observatory and the Peak Terskol Observatory ...
Nikolai Kiselev   +6 more
doaj   +1 more source

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