To place a satellite in a stable orbit around Earth, it must overcome Earth’s gravitational pull and air resistance in the lower atmosphere. Theescape velocityfor a satellite is around 7 miles per second. Even after escaping Earth, the pull of gravity contests a satellite’s tendency to rema...
Navigation satellites, like the kind used by your car's GPS, work well at this altitude. Sample specs for such a satellite might be an altitude of miles (20,200 kilometers) and an orbital speed of 8,637 mph (13,900 kph). Finally, it's possible to think about satellites in terms ...
The U.S. Geological Survey (USGS) produced its first topographic map in 1879, and it still produces them today. Developments in aerial photography and satellite imaging make these maps much more accurate and efficient to produce than in the days when they were created by hand. When the U...
Many missions, however, require a spacewalk, perhaps to deploy a satellite or make repairs. During a spacewalk, an astronaut must wear a space suit -- what NASA calls an extravehicular mobility unit (EMU) -- to protect and sustain him or her in the vacuum of outer space. Each EMU has ...
In this article, we'll peer into the guts of a typical satellite and then gaze through its "eyes" to enjoy views of our planet that Socrates and Newton could have barely imagined. But first, let's take a closer look at what, exactly, makes a satellite different from other celestial obj...
Brown, Gary. (2003). How Satellites Work. HowstuffWorks.com. 18 October 2003 . Hillier, Frederick and Gerald, Lieberman. (2001). Intro- duction to Operations Research, Seventh Edition. New York: McGraw Hill, 2001. Intelsat.com - Technical Resources - Satellite Basics. (2003). Intelsat. ...
Satellite Communication System: How Does It Work? Communication satellites are similar to space mirrors that let us bounce communications such as internet data, television, and radio from one side of the world to the other. It consists of three steps that might assist in explaining how it works...
The Moon: Our natural satellite When Is the Full Moon? The Full Moon is when the Sun and the Moon are aligned on opposite sides of Earth, and approximately100% of the Moon’s face is illuminatedby the Sun (see illustration). Some Full Moons are slightly less illuminated, as seen from ...
which should make it easier to talk to it. The group had captured the satellite.This was no a...
A GPS receiver has to have a clear line of sight to the satellite to operate, so dense tree cover and buildings can keep it from getting a fix on your location. GPS receivers and cell phones have a lot in common, and both are very popular. In the next section, we'll look at some...