Chapter 4 – Satellites (Launch Your Own Satellite)Posted: March 23, 2013
Launch your own satellites
The launch of Sputnik I by the USSR in 1957 started the space age and added a new word to the common vocabulary — satellite. In the astronomical context, this simply means a moon and our Moon (capital M of course) is the only natural satellite of Earth.
Since Sputnik I, literally thousands of artificial satellites have been sent into Earth orbit. A few have even been sent to orbit other planets like Venus, Mars and our Moon. On a clear night it is now rare for some 30 minutes to elapse before a satellite passes overhead on its silent progress about Earth — a point of light moving quite rapidly on a slight arced course amongst the stars.
The brighter satellites are usually in lower orbits moving from west to east across the sky (never in the reverse direction). The satellites in polar orbits (passing over the north and south pole at each revolution) are usually fainter and almost perfectly aligned to the Earth’s axis so that their movement is in a precise north/south or south/north direction.
Launching satellites can cost millions of pounds each so, before applying for a job at Mission Control, Houston, practise on the simulator programs to follow!