Low Earth Orbit of Satellites & Rubbish (N10)

Nations grabbing space in the orbits around the Earth for military dominance and economic competitiveness is nothing new. Examples are GPS (global positioning satellites) for identifying locations and Starlink for Internet connectivity. These efforts are lifting human civilization a big step above the Earth. Are we starting to live in 3D space from now on? This may be an interesting question but there is a sad issue as well. Technology is neutral but uses are not.

The biggest spacecraft in orbit at present with human astronauts onboard is the International Space Station (ISS) launched in 2000. Many satellites in orbit are as small as a one liter (about half of a breakfast table toaster) called CubeSat and the ISS is as large as two Boeing 747 jetliners joined length to length with big solar panel wings. Let us learn a bit about the Low Earth Orbit (LEO) in order to appreciate its correct use. Some nations have been abusing the orbits as revealed below.

To get up to an orbit around the Earth, we have to defeat gravity. Rockets are the vehicles to do this. Each rocket carries a payload such as one or more satellites or a human aircraft to construct or visit the ISS. LEO is the most popular orbit (implying there are other orbits). It is in fact not that low. It is about 2,000km above Earth, considering Mount Everest is 8km of altitude and civil airliners cruise at about 12km. At 2000km altitude, the air density and gravity pull are extremely low, so the energy required to cruise and maintain altitude is low. The temperature due to solar radiation is hostile without the protection of the atmosphere that wrap-protects the Earth. Daytime can be hotter than nighttime by 250 degrees C. Satellites cruise at about 8km/s (much faster than gun bullets) and take about 2 hours to orbit the Earth. At a location on Earth, a satellite is in sight for less than 20 minutes for data communication. Data travel time is about 5ms. Note: all figures given are approximate.

What happened to the rockets and satellites after their missions were completed? They could be blown up into small pieces and stay in orbit. An unofficial source from the UK Space Agency estimated 8,500 satellites and over a million pieces of debris larger than 1cm were in orbit. An ISS astronaut reported that a piece of debris went through the ISS like a bullet several inches away from him. This is just the beginning of man-made disasters. Nobody owns the orbits. We can use the orbits free of rent and choice. Can all nations apply sense and restraints and come to an acceptable governance structure? Bring your rubbish back home and sort it for landfill or recycling collection please.

Things in orbit above Earth are indeed different to what we have on Earth. Hope this article serves as a prompt to us to think differently from now on. Does it? Declaration: This article was written for the Continuing Professional Development program organized by Compucon New Zealand in the category of General Knowledge. General Knowledge is the source of ideas for creativity and innovations. The full set of articles can be found in the Resource Tab of www.cnz.co.nz.