Lets, Simply, Break it Down!

An orbit is the path that one object in space follows around another object on a regular, repeated basis, where the object that is rotated around is called the primary body. The second object which rotates around the primary object is known as a satellite. satellites can be either artificial or natural. An example of an artificial satellite is any spacecraft that is in orbit such as The International Space Station, for example, which is a man-made satellite. Examples of natural satellites are the Earth or the moon. There are other moons, comets and asteroids orbiting many planets all which are considered satellites.

Low Earth orbit (LEO) simply means an orbit around the Earth with an altitude near the bottom of the range of possible orbital distances. This distance is from 200 km 2,000 km from earth surface. LEO is home to the International Space Station (ISS) and the majority of satellites.

Credit: LTT Business Consulting

The Theory Behind it

The force of gravity, which what attracts humans to its surface, is actually what allows satellites – natural or artificial – to orbit a primary object. If gravity didn’t exist, we’d float out into space, and if that force didn’t exist, a satellite would fly off in a straight path.

An object in motion will stay in motion unless something pushes or pulls on it. Newton’s first law of motion is the name given to this proposition and it is the scientific justification behind the concept of orbits. Without gravity, an Earth-orbiting satellite would go in a straight line into space. It gets dragged back to Earth by gravity. The force of gravity pushing the satellite down is always at “fight” with the satellite’s desire to travel in a straight line, or momentum.

For an orbit to occur, the momentum of an object and the force of gravity must be balanced. If an object’s forward velocity (i.e momentum) is too high, it will fly past and not enter orbit. If the object’s momentum is insufficient, it will be pushed down and crash. When both forces are equal, the object will continually descend toward the planet, but it will never crashes on its surface because it is travelling sideways quickly enough.

What are the benefits of LEO?

To orbit in LEO, a satellite must move at roughly 7.8 kilometers per second to stay in this orbit, which takes around 90 minutes to complete an orbit of the globe.

Due to its proximity to Earth, LEO is beneficial for a variety of purposes. One of the most important benefits of LEO satellites is that they are cheaper to launch. This is because they do not require as much fuel and energy as higher orbit satellites. Beside this economic reason, It’s the most popular orbit for satellite imagery or remote sensing since it’s so close to the earth’s surface that it can acquire higher-resolution photographs. Furthermore, LEO can be utilized for communication, navigation, In addition to, military purposes. As mentioned earlier, The ISS is also in this orbit since astronauts may fly to and from it in a shorter distance and easy, relatively, fashion.

Credit: DEWESoft – Satellites Orbiting Earth (Jan 2022)

Individual LEO satellites, on the other hand, are less effective for communications operations because they move fast across the sky and require a lot of work to follow from ground stations. To overcome this disadvantage communications satellites in low-Earth orbit (LEO) sometimes serve as part of a huge constellation of many satellites to provide continuous coverage to the globe. This solution (i.e. constellation) is being utilized by all satellite applications in the LEO incase an increase of coverage around the earth is required.

What risks could be Associated with Low Earth Orbit Satellites?

Since the beginning of the 21st century, many factors have shaped the new era of the space sector. From the rapid advancement in space technologies and the introduction of small and nano satellites, to the commercialization of the space sector and the introduction of many key actors and concluding with the utilization of satellite constellations. All these factors indicate a bright insight to the future of space, however; at the same time, revealed a number of issues one, of them started with a collision between two satellites in 2009. The increased number of satellites introduced the issue of orbit congestion and space debris which effect have multiplied in the last ten years. This problem and others are mostly man-made, and the only solution to them is by setting international rules and regulation and agree on an enforcement tool to empower them.

Credit: NASA’s Goddard Space Flight Center/JSC