Results 31 to 40 of about 399,303 (277)
On the Secular Behavior of Irregular Satellites
The Astronomical Journal, 2004 Although analytical studies on the secular motion of the irregular satellites have been published recently, these theories have not yet been satisfactorily reconciled with the results of direct numerical integrations. These discrepancies occur because in secular theories the disturbing function is averaged over orbital motions, whereas instead one ...
Cuk, Matija, Burns, Joseph A.
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Orbits of the Irregular Satellites of Uranus and Neptune
The Astronomical Journal, 2022 Abstract We report on an ephemerides update for the irregular satellites of Uranus and Neptune, including Nereid. Our data set contains ground-based and Voyager 2 position measurements of the satellites. Some of the new observations were reduced with respect to the GAIA star catalog and represent high-quality, modern astrometry.
Marina Brozović, Robert A. Jacobson
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Determining Undersampled Coastal Tidal Harmonics Using Regularized Least Squares
Earth and Space Science, 2023 Satellite altimetry, which measures water level with global coverage and high resolution, provides an unprecedented opportunity for a wide and refined understanding of the changing tides in the coastal area.
Ruo‐Qian Wang +2 more
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IMPROVED INDOOR POSITIONING USING FINGERPRINT TECHNIQUE AND WEIGHTED K-NEAREST NEIGHBOUR [PDF]
ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2023 Global Navigation Satellite Systems are not effective when there is no direct line of sight between the user and the satellites, such as indoor environments and dense urban areas. Today, location-based services are used significantly due to their utility
S. Naderi Salim +6 more
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The Orbits of Jupiter’s Irregular Satellites
The Astronomical Journal, 2017 Abstract We report on the improved ephemerides for the irregular Jovian satellites. We used a combination of numerically integrated equations of motion and a weighted least-squares algorithm to fit the astrometric measurements. The orbital fits for 59 satellites are summarized in terms of state vectors, post-fit residuals, and mean ...
Marina Brozović, Robert A. Jacobson
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Progress in Earth and Planetary Science, 2017 Equatorial plasma bubbles (EPBs) have been a longstanding and increasingly important subject because they cause severe scintillations in radio waves from Global Navigation Satellite System satellites.
Tatsuhiro Yokoyama
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IRREGULAR SATELLITE CAPTURE BY EXCHANGE REACTIONS [PDF]
The Astronomical Journal, 2008 The study of the origin of irregular satellites remains important in planetary science because it provides constraints on the formation process of giant planets and probes the properties of a now-extinct planetesimal disk that existed at 5-30 AU early in solar system history.
David Vokrouhlický +2 more
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Direct imaging of irregular satellite discs in scattered light [PDF]
Monthly Notices of the Royal Astronomical Society, 2020 ABSTRACT Direct imaging surveys have found that long-period super-Jupiters are rare. By contrast, recent modelling of the widespread gaps in protoplanetary discs revealed by Atacama Large Millimetre Array suggests an abundant population of smaller Neptune to Jupiter-mass planets at large separations.
Loic Nassif-Lachapelle, Daniel Tamayo
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Control of colocated geostationary satellites [PDF]
, 1996 Control of the inter-satellite distances within a cluster of colocated satellites located in the same GEO window is examined with regards to the close approaches between pairs of satellites. Firstly, the orbital evolution and station keeping control of a
Hardacre, S.
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Comparing methods to estimate cloud cover over the Baikal Natural Territory in December 2020
Solar-Terrestrial Physics, 2022 The paper addresses the issue of how much cloud cover data obtained using satellite and model-interpolation techniques are suitable for monitoring the transparency of the atmosphere and determining conditions for airglow observations at a local ...
Podlesny S. V. +3 more
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