Author: Robert Earl Good Publisher: ISBN: Category : Artificial satellites Languages : en Pages : 57
Book Description
The behavior of satellite orbits under the perturbing effect of atmospheric drag is studied in order to determine the lifetime of a satellite. The wide extremes in drag coefficient, velocity, and density that a satellite experiences during one revolution is studied for possible methods of removing uncertainties in the lifetime predictions. By dividing the satellite lifetime into three phases - circularization, spiral decay, and terminal - approximatie methods can be developed to estimate the satellite lifetime in each phase.
Author: D. G. King-Hele Publisher: ISBN: Category : Languages : en Pages : 56
Book Description
The accurate prediction of satellite decay dates some months or years ahead remains one of the most difficult and intractable problems of orbital mechanics, chiefly because the lifetime depends strongly on the future variations in air density, which are at present not accurately predictable. In this paper simple graphical methods are presented for estimating the future lifetime of an Earth satellite from its current rate of decay, using theory adapted to an atmosphere with a realistic variation of density with height. The effects of the departure of the Earth and atmosphere from spherical symmetry, and the variations of density with time, are approximated by specifying correction factors. Orbits which experience serious lunisolar perturbations call for numerical-integration methods, and the uses of the computer programs PROD and PTDEC are described. Despite the many uncertainties, the remaining lifetimes of most satellites should be predictable with an accuracy of + or - 10% by these methods, which are based on many years' experience in making the monthly decay predictions for the RAE Table of satellites. (Author).
Author: Desmond George King-Hele Publisher: ISBN: Category : Artificial satellites Languages : en Pages : 19
Book Description
A geostationary satellite usually reaches its final circular orbit via a transfer orbit having apogee height near 36000 km and perigee height less than 600 km. The population of discarded rockets left in these transfer orbits is steadily increasing (there are now more than a hundred), and their likely lifetimes are usually assesed after lengthy numerical integrations to evaluate lunisolar perturbations. This paper gives a simple analytical method for predicting the lifetimes when the orbital inclination is between 20 deg and 30 deg, as often happens. Several approximations are made, but the errors should not exceed those from other sources. (Author).
Author: Tommaso Sgobba Publisher: Springer ISBN: 3319159828 Category : Technology & Engineering Languages : en Pages : 610
Book Description
Includes the proceedings from the 7th IAASS Conference, "Space Safety is No Accident," held in Friedrichshafen, Germany, in October 2014. The 7th IAASS Conference, “Space Safety is No Accident” is an invitation to reflect and exchange information on a number of topics in space safety and sustainability of national and international interest. The conference is also a forum to promote mutual understanding, trust and the widest possible international cooperation in such matters. The once exclusive “club” of nations with autonomous sub-orbital and orbital space access capabilities is becoming crowded with fresh and ambitious new entrants. New commercial spaceports are starting operations and others are being built. In the manned spaceflight arena a commercial market is becoming a tangible reality with suborbital spaceflights and government use of commercial services for cargo and crew transportation to orbit. Besides the national ambitions in space, the international cooperation both civil and commercial is also gaining momentum. In the meantime robotic space exploration will accelerate and with it the need to internationally better regulate the usage of nuclear power sources. Space-bound systems and aviation traffic will share more and more a crowded airspace, while aviation will increasingly rely on space-based safety-critical services. Finally, most nations own nowadays space assets, mainly satellites of various kinds and purposes, which are under the constant threat of collision with other spacecraft and with the ever increasing number of space debris. Awareness is increasing internationally (as solemnly declared since decades in space treaties) that space is a mankind asset and that we all have the duty of caring for it. Without proactive and courageous international initiatives to organize space, we risk to negate access and use of space to future generations.
Author: Robert Earl Good
Author: D. G. King-Hele
Author: Frank Garcia (Jr.)
Author: 
Author: Desmond George King-Hele
Author: Martin Company. Space Systems Division
Author: Jet Propulsion Laboratory (U.S.)
Author: 
Author: 
Author: Tommaso Sgobba