Ever since the Soviet Union launched the first-ever space satellite, named Sputnik 1, into the atmosphere way back in 1957, the area of space surrounding our earth has become increasingly populated.
There are already over 3,000 dead satellites and missile parts floating through space, as well as up to 900,000 fragments of space debris varying in size from 1 to 10 cm – all substantial enough to pose contact risks and delay active operations.
The number of in-space collisions is anticipated to climb as space traffic increases. Additionally, more and more satellites are being sent up into space and adding to the population of "dead satellites", therefore the number is expected to increase significantly over time.
Satellites, just like any other piece of modern machinery, will not last indefinitely.
Regardless of whether their mission is to monitor climate, analyze carbon dioxide in the atmosphere, or look out from Earth to examine the cosmos, all satellites, like older electrical appliances and household gadgets, eventually age, break down and expire.
So, what exactly happens when a dependable satellite dies? There are two options nowadays, depending on how far up the satellite is. Researchers will utilize its final amount of fuel to slow it down for the nearby satellites. It will drop out of orbit and break away in the atmosphere when this occurs.
As the satellite descends closer to The earth, the warmth from air resistance cooks it up, thereby burning the spacecraft into pure nothingness.
Nevertheless, for bigger satellites in low orbit, the technique is more complicated. It is difficult for these things to scatter entirely, raising the possibility of the satellite impacting the Earth's surface and inflicting devastation to the local people.
To prevent this, the satellites are taken down near Point Nemo, an area of marine inaccessibility in the Pacific. This aquatic cemetery is said to host 250 – 300 spacecrafts and is essentially the farthest point one can discover from any modern civilization.
What Is The Lifespan Of A Satellite?
There is no straight or easy answer to this question, essentially because the lifespan of a satellite will depend on various different factors.
Satellites have the potential to last hundreds of years, and some probably will. However, some other satellites will only remain operational for a few months. So, what factors come into play when discussing a satellite’s lifespan?
Usually, fuel is the only thing that can shorten a person's life. All satellites must undertake orbit and attitude maneuvers with comparatively tiny rocket engines and must keep an end-of-life oil stockpile for de-orbiting.
GEO fixed satellites must be dropped at least 500 miles above the surface GEO ring, and LEO satellites must adjust their orbit at the time of death so that the satellite is stripped away from orbit within 10 years, which implies decelerating the satellite, which in turn de-orbits.
The quantity of solutions available to orbiting thermal telescopes and similar satellites is also limited.
The lifespan of a satellite can also depend on its design and how well it has been made. Those satellites that are fitted with solar panels can generate electricity from the sun, while others rely on tanks or even quasi-nuclear units.
Certain satellites are meant to last 10 years, while others are only designed to last a few months. Since technological innovation rendered several of the original satellite systems obsolete, substitute 'birds' were deployed.
Many satellites 'failed' owing to a malfunction in one of their components and had to be decommissioned before their planned lifespan was over. Others failed to acquire a great enough orbit and re-entered the atmosphere, where they were destroyed.
How Far Up Are Satellites?
Once again, there is no straight answer to this question. The answer will all depend on what kind of satellite you’re looking at. Each satellite will sit at a different altitude depending on its specific purpose.
For example, Satellites that transmit television signals are placed in geostationary Earth orbits approximately 22,240 miles (35,800 kilometers) above ocean level (GEO).
Geostationary satellites, which are located above the equator, perform 1 rotation in precisely 24 hours, giving the impression that they are hovering over the same longitude. Since the satellite never dips underneath the horizon, you will always be able to enjoy your TV signal.
A satellite that is positioned in mid-Earth orbit (MEO) performs one rotation every 12 hours. MEO satellites orbit at heights of approximately 12,700 miles (20,400 km). This area is populated with Global Positioning System (GPS) satellites.
Low-Earth orbit (LEO) satellites have heights of less than 3,650 miles (5,900 km) over sea level. Such satellites move swiftly, completing an orbit in under 4 hours.
The Hubble Space Telescope (altitude 380 miles [610 km]), as well as the International Space Station (altitude 245 miles [400 km]), are 2 popular objects in LEO.
Satellites that observe the Earth employ a particular orbit known as a Sun-synchronous LEO. Because of the features of such orbits, a satellite can watch Earth with the Sun in the exact same spot day in day out. Satellites, such as NASA's Landsat collection, observe environmental conditions such as natural vegetation.
Every picture has the same brightness for such measurements to be accurate. Such orbits are also ideal for observation satellites, as they allow for the selection of the best illumination conditions for a certain target. Earth-orbiting satellites can be seen if they are above your skyline when the Sun is under it.