Results 1 to 10 of about 6,820 (225)
Observations of Halley's Comet [PDF]
Nature, 1910 I SAW Halley's comet through field-glasses on Sunday morning, April 24, at 3.40. It was then about 10° above the horizon, 20° to the left of Venus, and slightly under it. It was very distinct from 4.0 to 4.20. At its best, 4.15, I could just distinguish the head by the naked eye, but only for a minute.
H. C. Wilson, R. E. Wilson
+10 more sources
Not So Fast: A New Catalog of Meteor Persistent Trains
Journal of Geophysical Research: Space Physics, Volume 129, Issue 7, July 2024.Abstract This paper presents the results of a nearly 2‐year long campaign to detect and analyze meteor persistent trains (PTs)—self‐emitting phenomena which can linger up to an hour after their parent meteor. The modern understanding of PTs has been primarily developed from the Leonid storms at the turn of the century; our goal was to assess the ...
L. E. Cordonnier +4 more
wiley +1 more source
Commonsense morality and contact with value
Philosophy and Phenomenological Research, Volume 109, Issue 1, Page 410-430, July 2024.Abstract There seem to be many kinds of moral duties. We should keep our promises; we should pay our debts of gratitude; we should compensate those we've wronged; we should avoid doing or intending harm; we should help those in need. These constitute, some worry, an unconnected heap of duties: the realm of commonsense morality is a disorganized mess ...
Adam Lovett, Stefan Riedener
wiley +1 more source
Geophysical Research Letters, Volume 51, Issue 12, 28 June 2024.Abstract We use in situ plasma observations made by the Pioneer Venus Orbiter spacecraft to show for the first time that magnetosonic waves can couple the solar wind to the upper ionosphere and deposit energy there. The waves are generated upstream of Venus, are advected into the shock and propagate across the draped magnetic field, through the ...
C. M. Fowler +5 more
wiley +1 more source
The chemical diversity of comets [PDF]
Earth Moon Planets 105:267-272,2009, 2009 A fundamental question in cometary science is whether the different dynamical classes of comets have different chemical compositions, which would reflect different initial conditions. From the ground or Earth orbit, radio and infrared spectroscopic observations of a now significant sample of comets indeed reveal deep differences in the relative ...
arxiv +1 more source
Journal of Advances in Modeling Earth Systems, Volume 16, Issue 5, May 2024.Abstract The gravity wave drag parametrization of the Whole Atmosphere Community Climate Model (WACCM) has been modified to include the wave‐driven atmospheric vertical mixing caused by propagating, non‐breaking, gravity waves. The strength of this atmospheric mixing is represented in the model via the “effective wave diffusivity” coefficient (Kwave ...
Maria‐Vittoria Guarino +8 more
wiley +1 more source
Polarimetric studies of comet Halley [PDF]
arXiv, 2007 In the present work, the non-spherical grain characteristics of comet Halley are analysed using the T-matrix method at $\lambda = 0.365, 0.485$ and $0.684\mu m$ respectively. In order to analyse the polarisation data of comet Halley, the dust size distribution function derived by Das et al. (2004) for comet Halley is used in the present work.
arxiv
Three Interesting 15th and 16th Century Comet Sightings in Kashmiri Chronicles [PDF]
arXiv, 2003 This note is about three interesting 15th and 16th century sightings of comets in Kashmiri chronicles. We provide reasons for their identification as the 1468 S1, 1531 (Halley's), and 1533 M1 comets.
arxiv
Symplectic map description of Halley's comet dynamics [PDF]
, 2014 The main features of 1P/Halley chaotic dynamics can be described by a two dimensional symplectic map. Using Mel'nikov integral we semi-analytically determine such a map for 1P/Halley taking into account gravitational interactions from the Sun and the eight planets.
arxiv +1 more source
Coupling of acoustic and drift modes, harmonic modons in astrophysical dusty plasma and a new mode in the Comet Halley [PDF]
arXiv, 2022 This manuscript, presents a theoretical study of the linear and nonlinear characteristics of acoustic and drift waves in a bounded inhomogenious dusty plasma which has potential applications in space and lab environments. In this analysis, flow of all plasma particles is assumed to be along the axial direction whereas gradients in velocity are ...
arxiv