5,579 research outputs found
Colin Humphris
"Colin Humphris 2 Sqdrn. RAAF. 1941 - 1942 Author of - 'Trapped on Timor' (as a result of bombing of Darwin Feb. 19, 1942)".Colin Humphris. 2 Squadron, Royal Australian Air Force 1941 - 1942. Author of - 'Trapped on Timor' (as a result of bombing of Darwin February 19, 1942)
Orbital dynamics of high area-to-mass ratio spacecraft with J2 and solar radiation pressure for novel Earth observation and communication services
This paper investigates the effect of planetary oblateness and solar radiation pressure on the orbits of high area-to-mass spacecraft. A planar Hamiltonian model shows the existence of equilibrium orbits with the orbit apogee pointing towards or away from the Sun. These solutions are numerically continued to non-zero inclinations and considering the obliquity of the ecliptic plane relative to the equator. Quasi-frozen orbits are identified in eccentricity, inclination and the angle between the Sun-line and the orbit perigee. The long-term evolution of these orbits is then verified through numerical integration. A set of ‘heliotropic’ orbits with apogee pointing in the direction of the Sun is proposed for enhancing imaging and telecommunication on the day side of the Earth. The effects of J2 and solar radiation pressure are exploited to obtain a passive rotation of the apsides line following the Sun; moreover the effect of solar radiation pressure enables such orbits at higher eccentricities with respect to the J2 only case
Interview with Colin Wilson, part 4, undated
Interview with Colin Wilson, part 4, features an interview with author Colin Wilson in which he discusses his views regarding society and art, his reclusive nature, and the intellectual and fantastical elements of his works, undated
Interview with Colin Wilson, part 2, undated
Interview with Colin Wilson, part 2, features an interview with author Colin Wilson in which he discusses his views regarding society and art, his reclusive nature, and the intellectual and fantastical elements of his works, undated
Orbital dynamics of high area-to-mass ratio spacecraft under the influence of J2 and solar radiation pressure
This paper investigates the effect of planetary oblateness and solar radiation pressure on the orbit of high area-to-mass spacecraft. A planar Hamiltonian model shows the existence of equilibrium orbits with the orbit apogee pointing towards or away from the Sun. These solutions are numerically continued to non-zero inclinations and considering the obliquity of the ecliptic plane relative to the equator. Quasi-frozen orbits are identified in eccentricity, inclination and angle between the Sun-line and the orbit perigee. The long-term evolution of these orbits is then verified through numerical integration. A set of ‘heliotropic’ orbits with apogee pointing in direction of the Sun is proposed for enhancing imaging and telecommunication on the day side of the Earth. The effects of J2 and solar radiation pressure are exploited to obtain a passive rotation of the apsides line following the Sun; moreover the effect of solar radiation pressure enables such orbits at higher eccentricities with respect to the J2 only case
Orbit design for future SpaceChip swarm missions in a planetary atmosphere
The effect of solar radiation pressure and atmospheric drag on the orbital dynamics of satellites-on-a-chip (SpaceChips) is exploited to design equatorial long-lived orbits about the oblate Earth. The orbit energy gain due to asymmetric solar radiation pressure, considering the Earth's shadow, is used to balance the energy loss due to atmospheric drag. Future missions for a swarm of SpaceChips are proposed, where a number of small devices are released from a conventional spacecraft to perform spatially distributed measurements of the conditions in the ionosphere and exosphere. It is shown that the orbit lifetime can be extended and indeed selected through solar radiation pressure and the end-of-life re-entry of the swarm can be ensured, by exploiting atmospheric drag
Providence College Faculty Author Series 2017-2018: D. Colin Jaundrill
In this installment of the Faculty Authors Series, D. Colin Jaundrill (History, Providence College) discusses his newest book, Samurai to Soldier: Remaking Military Service in Nineteenth-Century Japan
Providence College Faculty Author Series 2017-2018: D. Colin Jaundrill
In this installment of the Faculty Authors Series, D. Colin Jaundrill (History, Providence College) discusses his newest book, Samurai to Soldier: Remaking Military Service in Nineteenth-Century Japan
Interview with Colin Jerolmack
Colin Jerolmack is an Assistant Professor at New York University
in Sociology and Environmental Studies. He is the author of The
Global Pigeon (forthcoming) and an alumnus of the Robert Wood
Johnson Foundation Scholars in Health Policy Program at Harvard
University
In memoriam Michel Colin
Op veel te jonge leeftijd is een begaafd Frans filmonderzoeker van ons heengegaan. Bezig met zijn favoriete sport, wielrennen, vond Michel Colin bij een verkeersongeluk de dood
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