Results 11 to 20 of about 92,259 (150)
Perspectives of Earth and Space Scientists, Volume 3, Issue 1, December 2022., 2022 Abstract The first discovery of the space age was in the field of space physics and occurred with the Explorer 1 launch in 1958 and its observations of the radiation belts encircling Earth. Space physics remained a young science into 1981 when I started graduate school, so young that there were no comprehensive textbooks on the subject.
Mona Kessel
wiley +1 more source
Space in 150 years: From fantasy through fiction to fact and function [PDF]
, 2015 In the last century and a half, space has moved from the realm of fantasy to everyday reality. In parallel, the way space has been regarded by the person in the street and the ideas of what access to space might be used for have evolved extraordinarily.
Southwood, DJ
core +1 more source
Photometric Confirmation and Characterization of the Ennomos Collisional Family in the Jupiter Trojans [PDF]
AJ, 165, 15 (2023), 2022 Collisional families offer a unique window into the interior composition of asteroid populations. Previous dynamical studies of the Jupiter Trojans have uncovered a handful of potential collisional families, two of which have been subsequently confirmed through spectral characterization.
arxiv +1 more source
Photon rockets in (anti-)de Sitter universe [PDF]
Phys.Rev.D78:044029,2008, 2008 A class of exact solutions of Einstein's equations is presented which describes accelerating photon rockets in de Sitter and anti-de Sitter universe. These are particular members of the Robinson-Trautman family of axially symmetric spacetimes with pure radiation.
arxiv +1 more source
Photon rockets moving arbitrarily in any dimension [PDF]
Int.J.Mod.Phys.D20:335-360,2011, 2010 A family of explicit exact solutions of Einstein's equations in four and higher dimensions is studied which describes photon rockets accelerating due to an anisotropic emission of photons. It is possible to prescribe an arbitrary motion, so that the acceleration of the rocket need not be uniform - both its magnitude and direction may vary with time ...
arxiv +1 more source
Bondi-Sachs metrics and Photon Rockets [PDF]
Gen.Rel.Grav.43:2729-2742,2011, 2011 We study the Bondi-Sachs rockets with nonzero cosmological constant. We observe that the acceleration of the systems arises naturally in the asymptotic symmetries of (anti-) de Sitter spacetimes. Assuming the validity of the concepts of energy and mass previously introduced in asymptotically flat spacetimes, we find that the emission of pure radiation ...
arxiv +1 more source
Origin theories for the eccentricities of extrasolar planets [PDF]
, 2007 Half the known extrasolar planets have orbital eccentricities in excess of 0.3. Such large eccentricities are surprising as it is thought that planets form in a protoplanetary disk on nearly circular orbits much like the current states of the solar ...
Namouni, Fathi
core +3 more sources
Simultaneous Sizing of a Rocket Family with Embedded Trajectory Optimization [PDF]
arXiv, 2023 A sizing procedure for a rocket family capable of fulfilling multiple missions considering the commonality is presented. The procedure aims to take full advantage of sharing a common part across multiple rockets whose payload capability differs entirely, ultimately leading to cost savings in designing a rocket family.
arxiv
Back to Basics: A Sanity Check on Modern Time Series Classification Algorithms [PDF]
arXiv, 2023 The state-of-the-art in time series classification has come a long way, from the 1NN-DTW algorithm to the ROCKET family of classifiers. However, in the current fast-paced development of new classifiers, taking a step back and performing simple baseline checks is essential.
arxiv
2006 Fragmentation of Comet 73P/Schwassmann-Wachmann 3B Observed with Subaru/Suprime-Cam
, 2009 We analyzed the Subaru/Suprime-Cam images of 73P/Schwassmann-Wachmann 3B and detected no fewer than 154 mini-comets. We applied synchrone-syndyne analysis, modified for rocket effect analysis, to the mini-fragment spatial distribution. We found that most
Ishiguro, Masateru +3 more
core +1 more source