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Meet some of the oldest "undead" spacecraft that are still going strong
Our little planet is surrounded by a huge amount of old tech from almost 65 years of space exploration. But not all of them are junk; some of these "dead" spacecraft may still function.
Science & Tech
Believe it or not, according to the Index of Objects Launched into Outer Space maintained by the United Nations Office for Outer Space Affairs, there were 7,389 individual satellites orbiting our little planet at the end of April 2021 (others place the number closer to 6,500). This number is only set to increase over time, with some estimates coming in at around 990 satellites being added to the mix every single year.
If true, by about 2028, we can expect to see somewhere in the order of 15,000 satellites orbiting Earth. This includes the massive increase in satellites scheduled to be deployed by companies like SpaceX in their Starlink constellation. The rise of small CubeSats, microsats, nanosats, etc, may also increase the number several-fold over the coming decades or so.
Of the satellites in space, most are used for either commercial telecommunications or navigational purposes, with others used for scientific or military purposes.
The vast majority, around 60%, is actually defunct and have been left to their fate.
Often referred to as "space junk", these long-dead satellites, as well as other pieces of metal and equipment are increasingly becoming a potentially serious navigational hazard for current and future spacecraft.
Vanguard 1C, for example, was launched in 1958. The American satellite was the fourth artificial Earth-orbiting satellite to make it to space, launching about five months after the more famous Soviet Sputnik 1.
Powered by solar cells, all contact was lost with Vanguard 1 in 1964. It still orbits the Earth (along with the upper stage of its launch vehicle), and is officially the oldest piece of "space junk".
"Space junk" is also introduced into orbit from the delivery vehicles used to get this stuff into orbit too. This can include small pieces of metal or paint flecks up to larger chunks of hardware like booster rockets, etc.
Why is space junk a problem?
If you've ever seen the film "Gravity", you will probably have, an admittedly dramatized, but basic idea. At present, while there is a lot of stuff up there, space is a big place and current levels of this junk are not mission-critical just yet.
The biggest risks associated with it all are from existing hardware already in orbit. Most modern satellites and other spacecraft have some form of collision avoidance system to help move them, briefly, out of the way of any incoming junk. The International Space Station (ISS) also has a similar system in place and it is used quite frequently.
But, even with all that in place, collisions can and do occur. In March of 2021, for example, a Chinese satellite broke apart after being hit by some space debris. Another similar event occurred in 2009.
But, can anything be done about it? Actually yes.
Various initiatives are currently underway to help clean up the space around Earth. Some strategies involve using existing satellites to grab pieces of space junk, while others focus on deorbiting satellites once they have reached the end of their usefulness, sending them careening into Earth's atmosphere to burn up instead of floating around in space for decades.
Not very sophisticated, perhaps, but it is effective nonetheless.
Examples include Surrey Satellite Technology's RemoveDEBRIS mission which used a large net to capture old satellites. While effective on larger objects, even this kind of system would miss the smaller stuff like paint flecks.
The United Nations has requested that all companies have a policy to de-orbit old space tech after 25 years or so, but this relies on compliance being voluntarily undertaken.
Time will tell if more effective strategies can be developed to manage space junk in the future. But, as you are about to find out, we may not want to clear up space entirely.
Some of these "dead" spacecraft may still function!
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