According to research published in The Conversion, humans have left a significant quantity of trash on the surface of Mars over the period of 50 years of exploration.
According to the United Nations Office for Outer Space Affairs, nations have sent 18 human-made objects to Mars in 14 distinct missions, several of which are currently ongoing.
Over 7000kg of rubbish was left by robotic exploration after 50 years
SpaceX/Unsplash
The three primary sources of debris on Mars are abandoned gear, idle spacecraft, and crashing spacecraft, as per Hindustan Times.
A lot of little, wind-blown rubbish has been discovered throughout the years, including the netting material recovered most recently.
On June 13, the Perseverance Rover uncovered a large, sparkling thermal blanket 1.25 miles (2 kilometers) distant from where it had landed.
Debris from their landing vehicles was discovered by both Curiosities in 2012 and Opportunity in 2005.
Another sort of debris on Mars' surface is made up of nine inactive spacecraft.
Among these spacecrafts are the Mars 3 lander, the Mars 6 lander, the Viking 1 lander, the Viking 2 lander, and others.
Destroyed spaceship pieces are another major source of trash. At least two spacecraft have crashed, while four more have lost touch soon before or immediately after landing.
The most difficult component of every Mars landing mission is safely descending to the planet's surface, which does not always happen as planned.
The total mass of all spacecraft dispatched to Mars is around 22,000 pounds (9,979kg). After subtracting the 6,306 pounds (2,860kg) of the currently working vessels on the surface, there is 15,694 pounds (7,119kg) of human garbage on Mars.
Scientists are now most concerned about the risk that garbage on Mars presents to ongoing and future missions.
The Perseverance crews are tracking every piece of debris they come across and checking for anything that might contaminate the samples the rover is collecting.
NASA engineers have also considered the chance of Perseverance becoming entangled in landing debris, although they have judged that the danger is negligible.
The historical background of the Martian debris gives it significance. The spaceship and its components represent mankind' earliest efforts toward planetary exploration.
What are the chances of getting struck by falling space debris?
Earlier this year, two different cases of space debris crashing down to Earth in unexpected areas occurred, as per the BBC.
The uncontrolled re-entry of a Chinese Long March 5B rocket over Malaysia was quickly followed by reports in July of certain spacecraft pieces turning up in remote New South Wales, Australia, which have now been proven to be from a SpaceX Crew-1 mission.
As the space industry expands, such occurrences are likely to become increasingly common - and potentially dangerous.
But how big of a danger is there?
The term "space trash" refers to the components of a space system that are no longer needed.
It might be a satellite that has reached the end of its operational life (like the International Space Station will in 2031), or elements of a rocket system that have served their function and are destroyed.
China has launched three Long March 5B rockets to date, each of which has been deliberately left in an uncontrolled orbit. This meant they had no idea where they were going to land.
Concerning the SpaceX debris discovered in Australia's Snowy Mountains, SpaceX de-orbits its rocket sections in a controlled manner and designs other components to burn up upon re-entry into Earth's atmosphere.
However, as the newest news shows, these things do not always go as planned.
So far as we know, just one person has been hit by it. Lottie Williams, a resident of Tulsa, Oklahoma, was hit in the shoulder by a fragment in 1997.
It was around the size of her hand and was believed to have originated from a Delta II rocket. She picked it up, took it home, and reported it the next day to authorities.
However, as more and more items enter space and return, the odds of being struck by someone or anything are growing.
This is particularly true with massive, uncontrollable things like the Long March 5B.
There are numerous various estimates of the likelihood of space debris colliding with someone, but the majority are in the one-in-10,000 range.
This is the likelihood of somebody getting struck, wherever in the globe. However, the chances of a specific person getting hit are one in a trillion.
These estimations are based on a number of criteria, but we'll focus on one in particular for the time being.
The graphic below depicts the orbital path taken by the recent Long March 5B-Y3 rocket during its last 24 hours (various objects have different orbital courses), as well as its re-entry site, which is highlighted in red.
