Artificial Satellites

A satellite EPIRB (Emergency Position Indicating Radio Beacon) is designed to automatically transmit distress signals to search and rescue satellites in the event of an emergency at sea. When activated, it sends out a unique digital signal that includes the vessel's identification and location information, allowing rescue teams to locate and assist individuals in distress. These devices are essential for enhancing maritime safety, especially in remote areas where traditional communication methods may be unavailable.

America launched its first satellite, Explorer 1, on January 31, 1958. This marked a significant milestone in the Space Race, occurring shortly after the Soviet Union had launched Sputnik 1 in 1957. Explorer 1 was instrumental in the discovery of the Van Allen radiation belts. Its successful launch demonstrated the United States' growing capabilities in space exploration.

Radio waves are the type of radiation that send information to and from satellites. These electromagnetic waves are used for communication, enabling the transmission of signals for various applications such as television, internet, and GPS. The frequency and modulation of these radio waves can be adjusted to facilitate different types of data transfer, ensuring reliable connectivity between satellites and ground stations.

A satellite in a higher orbit moves more slowly due to the weaker gravitational pull it experiences compared to satellites in lower orbits. According to Kepler's laws of planetary motion, the orbital period increases with distance from the central body; thus, satellites further from Earth take longer to complete an orbit. This slower speed is a result of the balance between gravitational force and the satellite's inertia, which diminishes with increased distance from the planet.

Artificial satellites are crucial for studying remote locations like outer space as they provide a stable platform for various scientific instruments to collect data from afar. Equipped with cameras, sensors, and telescopes, they can capture images and gather information about celestial bodies, cosmic phenomena, and environmental conditions. Additionally, satellites facilitate continuous monitoring, enabling researchers to analyze changes over time, which is vital for understanding the universe's dynamics and origins. Their ability to operate outside Earth's atmosphere allows for clearer observations, free from atmospheric interference.

A satellite phone could (and can still) give you mobile phone reception ANYWHERE in the world.

The pressurized sphere made of aluminum alloy had five primary scientific objectives: Test the method of placing an artificial satellite into Earth orbit; provide information on the density of the atmosphere by calculating its lifetime in orbit; test radio and optical methods of orbital tracking; determine the effects of radio wave propagation though the atmosphere; and, check principles of pressurization used on the satellites.

Whenever you talk about speed, it has to be relative to something, and if you want to

compare two speeds, then they both have to be relative to the same thing, which you

haven't identified.

Relative to my left thumb, one of those speeds (mine) is zero, and the other one is

nominally zero.

Relative to the tip of a blade on the propeller of an aircraft in flight, or a flea on the

fan-belt of my car, both of those speeds are constantly changing in very complex ways,

and in order to describe either of them, I'd need a ton of additional information that you

haven't provided.

SOHO was launched on December 2, 1995.

Gravity causes satellites to orbit the Earth. The satellite moves laterally relative to the Earth while the Earth's gravity pulls it down toward the Earth, resulting in a system where the satellite remains at the same distance from the Earth.

It is simplest to understand gravitational orbit if from the standpoint of a fixed system with a spherical Earth at the center and the satellite directly above it. Drawing an imaginary line through the Earth and the satellite (call this the vertical center line) and another imaginary line through the Earth perpendicular to (i.e. at a 90-degree angle to) the vertical center line.

Initially, gravity is pulling directly down, toward the center of the Earth, and the satellite is moving perpendicular to this force -- for this argument, we'll say it's moving directly to the left. Now, as it moves to the left, away from the Earth laterally, the Earth's gravity pulls it downward.

In this next step, it is closer to the Earth vertically but further from the Earth laterally. The Earth's gravity, pulling toward itself, now pulls slightly laterally because the object is no longer directly above but now slightly to the left of our imaginary vertical center line. Thus, it begins to slow down, and the further it gets laterally from the Earth, the greater the portion of the Earth's gravitational force is dedicated to pulling to the right. This also means that the downward-pulling part of the Earth's gravity decreases as the object nears the horizontal center line.

After many of these steps, with the force of Earth's gravity pulling less and less strongly downward and more and more laterally, the satellite now stops moving laterally due to the force from gravity. However, the force from gravity has also accelerated the satellite downward, and now it's moving quite quickly downward -- downward, however, is no longer toward the Earth because the ball has moved quite a bit out to the left before being slowed to a stop laterally by the Earth's gravity.

If the satellite is in orbit, meaning that it has the correct initial speed for the distance from the Earth, then when the satellite is entirely stopped from moving to the left, it will be moving downward at the same speed as the initial speed to the left (when the satellite was on the vertical center line). At this point, the Earth is pulling the object directly toward itself, which is directly to the right. It is no longer pulling down at all. The object then begins to "fall" to the right. In the next instant, the object has begun to move to the right, but has fallen downward past the horizontal line, so Earth's gravity now pulls upward to bring the satellite closer to itself.

While it is easy to look at orbit from a fixed system with the satellite moving around the Earth, it's also true that because the Earth is roughly spherical, the system can be viewed the same way no matter where it is. When the satellite is directly to the left of the Earth in the previous explanation, the picture can be rotated to the right 90 degrees to see the exact same picture as when it started. At every position in the orbit around the Earth, the picture of the satellite can be rotated to the left or right to be the same as any other point on the orbit.

This ultimately means that the satellite always just stays at the same distance from the Earth moving at the same speed perpendicular to the Earth's gravity. The Earth pulls the satellite closer to itself, but the satellite is moving quickly enough that gravity just changes the direction of the satellite rather than the distance.

It can be easily proven mathematically that this particular argument works; however, math can be difficult to visualize physically and a proper argument requires some knowledge of calculus.

Note that there is no correct "speed" of orbit or distance from the Earth. Objects that are closer to the Earth fall more quickly and therefore require a higher speed perpendicular to Earth's gravity to remain in orbit. This occurs naturally, just as a ball on a string will spin more quickly if you pull harder on the string. Similarly, objects can orbit more slowly at greater distances.

160°

Solar Marx

well earth has different radius at poles and equator .At poles it is 6357 km and at equator it is 6378km hence have a diffrence of 21 km.Basically oblateness mean to be flat at two the ends of sphere like a egg.This cause a adiitional force of gravity on satellite when they comes in top of equator.This addition force tends satellite to accelerating it to lower latitute and deaccelerating while going to highter latitue.This shape at equator is calles equitorial bulge.

Iqbal singh thakur

auther

www.allsab.com

Yes. The reason they normally don't is a question of energy (or cost).

Since the Earth turns west to east you would have to overcome that component and THEN get up to orbital speed.

Venus is unique in that it and Mercury are the only planets in the solar system with no natural satellites. Currently the European Space Agency (ESA) has a satellite named Venus Express orbiting the planet.

Quoting Wikipedia: The spacecraft was placed in a 525 km (326 mi), circular, polar, sun-synchronous orbit for its 10 month mission, during which it has taken 1.5 million images, one every 11 seconds.

Jupiters Moon: Io

Securities and Exchange commission

Why Fresnel zone affecting satellite and ground communication?

In theory, 2 satellites in diametrically opposite geosynchronous orbits could cover the planet. In order for the satellites to communicate, a minimum of 3 would be needed, each at a 60 degree angle to the others. At this point, the strength and quality of coverage increases proportionally to the number of satellites.