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Artificial Satellites
Artificial Satellites are objects launched from earth to orbit earth or other planets. Satellites are used for communication, remote sensing, weather forecasting, and other purposes. This category is for questions about satellites in general or specific satellites.
1,932 Questions
Apollo 11, the first crew to land on the surface of the moon was commanded by Neil Armstrong, also the first to disembark the Eagle and make history as the first man on the moon. Apollo 11 cleared the tower on July 16, 1969 and landed on the surface of the moon on July 20, 1969. Buzz Aldrin was the Lunar Module Pilot and Michael Collins served as the Command Module Pilot orbiting earth as the other two astronauts explored the moon. They safely returned to earth on July 24, 1969.
What is the name of the world's first satellite launched in 1957 by soviet union?
It was called the 'Sputnik' and was put into orbit on October 4th, 1957. The timing was 'tweaked' to mark the 40th anniversary of the Russian Revolution of 1917.
How many communication satellites are currently orbiting the earth?
The numbers vary among estimates, but there are between 2100 to 2200 functioning artificial satellites in Earth orbit. Russia has the greatest number at around 1324. The U.S. is second with 658 satellites in orbit.
How many hours do satellites take to complete one orbit?
It depends on how high the satellite's orbit is.
Kepler's Third Law states that the further away a satellite is from its parent body, the longer its orbit takes. (This same law explains why our planet circles the Sun faster than, say, Jupiter.) Some examples:
- Geosynchronous (and geostationary) satellites, which lie about 22,200 miles above the Earth's surface, by definition take exactly one full day to complete one orbit.
- The International Space Station, by contrast, is only about 220 miles away -- 1/100th the distance -- and completes an orbit in just over 90 minutes.
- At the opposite extreme, our moon takes 27.3 days to orbit the Earth, from a whopping average of 239,000 miles away.
Are satellites luminous or non-luminous?
Non-luminous.
Objects which produce light of their own or give out or emit their own light are called luminous objects.
Objects which do not produce light of their own, on the other hand, are called non-luminous objects.
Luminous objects are objects like stars, sun and other celestial bodies which give out their own light.
Objects surrounding us are not such light emitting objects. Therefore, we are surrounded by non-luminous objects.
Which waves are used by satellites for communication?
On a fiber-optic line: light. That's the only kind of energy that passes through the fiber. On wires: electrical signals in the form of AC currents. Without wires or anything else to carry the info: electromagnetic waves, such as for example -- radio, TV, microwave, infra-red or visible light beam. Some advantages of electromagnetic signalling are: -- easy to generate, and to impress information onto it -- easy to radiate and detect over great distances using small amounts of power -- easy to focus the available power in the desired direction of communication -- easy to separate the signal you want out of the flood of signals from thousands of other people all using the same technology to communicate -- no expense or physical infrastructure required between the end-points (running fiber via satellites would be difficult and expensive)
How many man made satellites are pass Pluto?
None has ever visited Pluto
Voyager 1, now the most distant human-made object in the Universe.Voyager 1 is almost 70 times farther from the Sun than the Earth. Out there, the Sun is only 1/5,000th as bright as here on Earth. It is extremely cold, and there is little solar energy to keep the probe warm and to provide electrical power. As of December 7, 2007, Voyager 1 is over 15.67 terameters (15.67×1012 meters, or 15.67×109 km, 104.7 AU, 14.52 light-hours, or 9.79 billion miles) from the Sun
Why do satallites have to stay in the equotorial plane?
Staying at the "same point" (i.e., above the same location on Earth) is only
important for a Geosynchronous satellite, which must occupy a very high orbit.
Most satellites (and the International Space Station) are in lower orbits, which
means they orbit the Earth faster than it rotates, so they don't stay in the
same place.
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Answer #1:
Now to deal with the question . . .
If the satellite is going to be used by non-technical people with little 'dishes'
on the corner of their house or garage, it's important that they not need to
move their dish to follow the satellite across the sky. If people couldn't "set
it and forget it", there would be no Dish network or Direct TV or any of the
others, because very few customers would be willing to do what it takes to
keep their dish tracking the satellite. Sure it could be automated, with a
motorized mechanism that constantly steers the dish to follow the satellite.
But that would cost 20 times what those dinky dishes cost now, and again,
the operators would not "have a business". The only way that this whole
scheme of satellite-direct-to-the-home can work is to make the satellite
motionless in the sky. The installer comes to your house, mounts the dish,
'finds' the satellite, points the dish in that direction, and locks it permanently
in that position. That's the only way the business model can work.
How many satellites does it take for GPS to find something?
Your receiver must pick up at least 4 to get an accurate 3D lock.
If your receiver can safely assume you are on or near surface of earth it can get a good 2D lock with just 3. This is usually a safe assumption to make, especially with civilian receivers.
Less than 3, all it can do is set its clock.
Why must a satellite have a distinct up link and down link frequencies?
These are frequencies used for satellite communications.
Usually in the Gigahertz bands.
Uplink is on a differenct channel to downlink, to avoid interferece.
The Uplink, is the signal sent to the satellite, via a dish antenna, which focuses the signal in the direction of the satellite.
On board the satellite, this signal is changed and re-transmitted, on a different frequency (Downlink), and beamed back to earth.
This way huge distances can be covered on earth, despite the curvature and with minimal power.
How do satellites send imges to earth?
Satellites transmit signals using highly directional electromagnetic waves.
Electromagnetic waves are used all the time in today's technology; microwaves use microwaves which are the same as mobile phones, televisions use ultrahigh frequency waves, visible light is in fact electromagnetic waves.....
Where our mobile phones use multi-directional antenna satellites use parabolic dishes to produce unidirectional signals which are transmitted to receiver stations on the earth. A sky box is an example of one such receiver where only a download link can be established, i.e you cannot use your set top box to control the satellite.
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In Addition (added by another user)
Microwaves are used because their wavelength is long and thin, they don't refract much making them accurate. Furthermore, radio waves cannot be used as when under 30 MHz they reflect of the ionosphere and if they are above, their wavelength makes them refract too much. Strong signal strengths are needed as when above 30 GHz things like rain, dust etc reduce signal strength.
Hope this helped.
What is the relation between the planets and their satellites?
It is currently impossible to name every planet in existence. The known planets in our solar system (listed with planet type and number and names of known moons) are as follows (in ascending order of orbital radius):
- Mercury (Terrestrial) [0]
- Venus (Terrestrial) [0]
- Earth (Terrestrial) [1, Luna]
- Mars (Terrestrial) [2, Phobos and Deimos]
- Ceres (Dwarf planet) [0]
- Vesta (Protoplanet) [0]
- Pallas (Protoplanet) [0]
- Jupiter (Gas giant) [66]
- Saturn (Gas giant) [62]
- Uranus (Ice giant) [27]
- Neptune (Ice giant) [13]
- Orcus (Dwarf planet) [1, Vanth]
- Pluto (Dwarf planet, binary) [4, Nix, Hydra, P4, P5]
- Charon (Dwarf planet, binary) [4, Nix, Hydra, P4, P5]
- Haumea (Dwarf planet) [2, Hi'iaka, Namaka]
- Quaoar (Dwarf planet) [1, Weywot]
- Makemake (Dwarf planet) [0]
- 2007 OR10 "Snow White" (Dwarf planet) [0]
- Eris (Dwarf planet) [1, Dysnomia]
- Sedna (Dwarf planet) [0]
a man made satellite is a satellite made by man, and sent into space to orbit around a planet, star, or other body in any solar system to gather information and pictures about it.
Why is it important for a satellite to maintain its speed?
The first weather satellites allowed meteorologists and forecasters to see Earth from space and get a larger picture of cloud formations from above. The program was called TIROS and there were 10 satellites in the series. (A good link is provided below) Prior to TIROS, there were few options available to help meteorologists to predict the weather.
Weather satellites used in forecasting disaster?
Satellites above the atmosphere can get a clear, big picture of Earth's cloud formations. By analysing these cloud patterns, meteorologists can forecast how these clouds will change and move, and predict the weather, be it rain or shine, for many areas. For example, hurricanes can be easily spotted from satellites but not easily spotted from ground due to its size, and thus satellites come in very helpful. Also, infra-red satellite forecasting can also determine the temperatures in different areas on Earth's surface, which aids meteorologists in finding out cloud heights, cloud types, water cycles and sea surface termperatures (an important factor in the formation of hurricanes).
Do satellite travel the same direction as the earth?
Yes - usually. The reason for this is that doing this requires less energy to launche them, since the launching rocket will use the Earth's rotation.
13 Degrees east can mean many things, be more specific.
Dr. Fred Whipple came up with the idea that comets are "dirty snowballs"; primarily ice and frozen gasses, holding a large quantity of dust, pebbles and rocks.
If the evidence hadn't supported his theory, he would have had to go back and come up with a different theory. That's the way science works - or at least, is SUPPOSED to work.
What are the names of UK's satellites?
* Ariel 1 - First UK launched satellite. * Beagle 2 - Failed attempt to Mars. * Orba X2 - First attempt atop a British rocket - failed * Prospero X3 - First successful launch atop a British rocket * Skynet series. Military. (Nothing to do with Terminator) * UK-DMC2 - Earth Imagining.
See related links for more information
What are the uses of satellites?
Imagine what we could NOT do without satellites!
- No cell phone networking across towers, across the world.
- No watching your favorite shows on TV.
- No Internet.
- No GPS system.
- No airline flights -- they'd all crash into each other.
- No ocean going ships battling the waves, whether you want to go on a cruise or you want to eat fish in a restuarant.
- No trusty weather forecasts. Forget about knowing if there will be a hurricane, tornado, or even rain. We'd be living back in the 1910s when no one could turn on a TV and see satellite weather images.
- We'd never have those fantastic Google Maps or earth images taken from space.
What is the difference between a goes satellite and a poes one?
The GOES are as they say, Geostationary 22,300 miles above the Earth's surface. Gathering information every 15 to 30 minutes.
The POES are Polar-Orbiting because the orbit from one polar regoin to the next staying mostly parallel to the meridian line 530 miles above Earth's surface. With the Earth's rotation from west to east the images observe to the west of the last scanned area. The satellites orbit 14.1 times a day putting them at different locations at different times of the day.
