10 things to know about space debris and junk in orbit around Earth; how dangerous is that for space missions?
- There are roughly 23,000 pieces of debris larger than a softball orbiting the earth.
- They travel at speeds of up to 17,500 miles per hour, fast enough that a relatively small piece of orbital debris can damage a satellite or spacecraft.
- Even tiny patches of paint can damage a spaceship when it travels at these speeds.
Do you remember the opening sequence of the 2013 film Gravity with Sandra Bullock and George Clooney? High-speed debris meets Explorer and Hubble, tearing the astronauts from the shuttle and letting them tumble through space. It’s been dubbed one of the scariest scenes ever.
In reality, a satellite destroyed once can form a catastrophic cloud of space debris. Space debris circulating around the earth is not an imaginary problem. A piece of space junk crashed into the International Space Station and recently damaged the robotic arm of the orbiting laboratory. A routine inspection on May 12 found a hole in the arm’s protective heat wrap, but the nearly 60-foot robotic appendage remains functional, officials from NASA and the Canadian Space Agency confirmed.
This incident is reminiscent of the growing threat of debris in orbit as the narrow space band around the earth becomes more and more overcrowded with satellites, spent rocket fragments, and other wayward objects.
What we see on earth as the lifelines and signs of progress – the satellite systems for telecommunications, GPS and other everyday conveniences – are potential debris in the near future.
Here are 10 things about space debris:
- The first random collision between two satellites in orbit occurred on February 10, 2009 at 16:56 UTC at an altitude of 776 km over Siberia, reports ESA. A private American communications satellite, Iridium-33, and a Russian military satellite, Kosmos2251, collided at 11.7 km / s. Both were destroyed, and more than 2,300 trackable fragments were created, some of which have since re-entered (i.e., disintegrated and re-entered the atmosphere where they were burned).
- The US Department of Defense tracks more than 27,000 space debris, including approximately 23,000 objects larger than a softball.
- These debris fly through orbit at speeds of up to 28,000 miles per hour, posing a threat to functioning spacecraft and a safety hazard to astronauts aboard the International Space Station.
- Since the ISS began operating, NASA has had to perform at least 26 special maneuvers to avoid orbital debris that passed too close to the outpost in orbit.
- Space debris includes both natural meteoroids and man-made (man-made) orbital debris. Meteoroids are in orbit around the sun, while most man-made debris is in orbit around the earth (hence the term “orbital” debris).
- In 1996, a French satellite was hit and damaged by wreckage from a French missile that had exploded a decade earlier.
- On February 10, 2009, a decommissioned Russian spacecraft collided with a functioning US commercial spacecraft Iridium and destroyed it. The collision added more than 2,300 large, trackable debris and much smaller debris to the inventory of space debris.
- China’s 2007 anti-satellite test, which used a missile to destroy an old weather satellite, added more than 3,500 large, trackable debris and much smaller debris to the debris problem. ”Just the Chinese Feng Yun-1C deployment in the January 2007 increased the population of trackable space objects by 25%, according to the European Space Agency.
- In more than 60 years of space activity, more than 6050 launches have resulted in approximately 56,450 tracked objects in orbit, of which approximately 28,160 remain in space and are regularly tracked and maintained by the US Space Surveillance Network and maintained in its catalog, which includes objects larger than approximately 5- 10 cm in low earth orbit (LEO) and 30 cm to 1 m in geostationary (GEO) heights. Only a small fraction – around 4,000 – are intact, functional satellites today.
- This large amount of space hardware has a total mass of more than 9,300 tons.
NASA says that sometimes these encounters are known well in advance and it is time to move the International Space Station off in what is known as a “debris avoidance maneuver” to keep the object out of the box.
In other cases, the tracking data is not accurate enough to warrant such a maneuver, or the narrow pass is not recognized in time to perform the maneuver.
(Thousands of satellites threaten to collide with space debris. Image: UN Office for Outer Space Affairs / European Space Agency)
What if the rubble is unavoidable and disaster threatens?
- In such cases, the control centers in Houston and Moscow may jointly agree that it is best to move the crew to the Russian Soyuz or U.S. crew starships, which are used to transport people to and from the station.
- This gives enough time to isolate these spaceships from the station by closing the hatches in the event of a damaging collision.
- The crew could leave the station if the collision causes a loss of pressure in the life support module or damages critical components.
- The spacecraft serve as lifeboats for crew members in an emergency.
- Mission Control also has the option of taking additional precautionary measures, such as having the crew close the hatches between some modules of the station if the probability of a collision is high enough.
Can the debris be removed? The UN Office for Space Affairs has a plan:
According to the World Economic Forum, on March 22, 2021, a vehicle that resembles a washing machine with wings was catapulted into the sky from Kazakhstan on a Soyuz rocket, demonstrating the core technologies required for docking and removing space debris. “
The launch of the ELSA-d mission – to demonstrate a breakthrough method for the collection and safe removal of space debris using magnetic recovery – is part of an effort by a number of companies to conduct a heavenly garbage collection exercise on a grand scale.
ELSA-d was developed by the Japanese start-up Astroscale and consists of two satellites stacked on top of each other. The first part is a service boat designed to safely remove debris from orbit. This is docked to a smaller satellite, which reproduces a piece of space junk during test flights, reports the WEF.