âYou let your tour guide know how you much you enjoyed the experience they provided by your tip; 15% is average. Carriage Drivers: Similar to walking tours, when you pay $85 for a horse & buggy ride in St. Augustine, itâs hard to know how much to tip.
These objects are. launched into space and orbit Earth, or. another body in space, and carry instru-. ments for collecting information and. communicating it back to Earth. There are approximately 3,000 satellites operating. in Earth orbit, according to the US Government. There are another 8,000 dead satellites and rocket. parts in orbit. Smaller orbital debris or âspace junkâ. is of growing concern as it can damage active sat-. ellites. There are currently over 20,000 pieces of. trackable debris 3.6 inches (10cm) or larger result-. ing mostly from explosions and collisions.
Many modern GPS receivers use a combination of both GPS and the Russian GLONASS satellites for improved coverage and accuracy. The GPS system currently has 31 active satellites in orbits inclined 55 degrees to the equator. The satellites orbit about 20,000km from the earth's surface and make two orbits per day. The orbits are designed so that there are always 6 satellites in view, from most places on the earth. GPS uses a lot of complex technology, but the concept is simple. The GPS receiver gets a signal from each GPS satellite.