|
|
Increasing the safety of the operation of spacecraft in Earth orbits
Bartoněk, Jaroslav ; Kovařík, Vladimír (referee) ; Zikmund, Pavel (referee) ; Daněk, Vladimír (advisor)
This dissertation thesis addresses the most significant risks manned and unmanned missions in Earth orbit must face to. It states that the dominant risks are collisions with particles of Space debris, phenomena related to solar activity and galactic radiation. It notes that the solution of Space debris problems belongs to the engineering and application domain, while solar activity requires further scientific research. The review showed that the source of risk to Earth is primarily the solar corona. Thus, the thesis is focused on research of possibilities of its observation by artificial satellites from the point of view of celestial mechanics. Since the observation is only possible during total solar eclipse, the thesis deals with a previously unused method of solar eclipse observation by artificial satellites from low Earth orbit using the Moon as occulting body. It illustrates methods of calculation of orbital elements of these satellites, their important properties, advantages, and disadvantages. It shows that these orbits exist and lead to observations of duration fully comparable to usual ground-based eclipse observation. In an innovative way the solution of so-called Lambert’s problem is applied. This algorithm is used to find orbits leading to two successive observations separated by a given time interval. This allows more efficient use of time of the mission and provides more scientific data. Marginally, the use of the planet Mercury as occulting body is studied.
|
guest ::
