Everything Everywhere Daily: History, Science, Geography & More - Space Junk

Episode Date: February 19, 2021

In 1957, Sputnik was launched into orbit as the world’s first artificial satellite. Today, 64 years later, there are more than 1,000,000 objects larger than 1 centimeter floating around the Earth. Almost all of those objects in orbit were not put there intentionally. Learn more about space junk, the problem, and possible solutions, on this episode of Everything Everywhere Daily. Learn more about your ad choices. Visit megaphone.fm/adchoices

In 1957, Sputnik was launched into orbit as the world's first artificial satellite. Today, 64 years later, there are more than a million objects larger than one centimeter floating around the Earth. And almost all of these objects in orbit were not put there intentionally. Learn more about space junk, the problem, and possible solutions on this episode of Everything Everywhere Daily. What if your perceptions about the past were wrong? ThruLine is a podcast that takes you back in time to uncover the parts of the story that may have gone unnoticed. It effectively turned day into night.

And how it shaped the world now. Time travel with us every week on the Thuline podcast from NPR. This episode is sponsored by CuriosityStream. If you're interested in the space program and planetary missions, you have to check out CuriosityStream. They have shows on the recent Hayibusa asteroid sample mission, the Cassini mission to Saturn, and the current Perseverance Marsland. They have many, many more shows, including one on Space Junk.

Price is start as low as $2.99 per month or $1999 per year. One of the cheapest streaming services available online. If you love to learn, then start your subscription by visiting everything-everywhere.com or by clicking on the link in the show notes. Since 1957, humanity has been launching satellites into Earth orbit. It's estimated in the last 64 years, almost 9,000 satellites in total have been put into orbit. For the vast majority of space age, there was never a plan for what would be done with the satellites after their lifetime. They were launched without any thought as to how or if they could ever come down.

Of the 9,000 or so satellites, 5,000 are still in orbit. 2,000 are in service, and 3,000 are dead. These satellites are usually quite large. They can vary in size from a bus to a box, and they aren't the real problem when it comes to space junk. The big problem is debris. When you send up a rocket, there's all sorts of miscellaneous parts on the upper stage of the rocket that holds the satellite that'll go into orbit with it. This can include metal panels, bolts, screws, and even flakes of paint. You'd think that given how big space is, that space junk might not be a problem.

As Douglas Adams noted, quote, space is big, really big. You just won't believe how vastly, hugely, mind-bogglingly big it is, unquote. Suppose you add a million pennies. That would be enough to easily fit in a lot. minivan. Now let's suppose you distributed those pennies all over the world, including the ocean and Antarctica. Each penny would have 197 square miles of space, or a single penny would have a square which was 14 by 14 miles. Factor in that the lowest Earth orbit is a sphere larger than the Earth, and that there's a vertical dimension where we could put pennies at different elevations,

then it wouldn't seem that space junk was a big problem. If the objects just sat there, that's true. It wouldn't be a problem. However, all that junk isn't just sitting there. It's orbiting the Earth at extremely high speeds. Any piece of space junk is probably traveling at at least 17,000 miles per hour. When something is traveling that fast, no matter how small it is, it can cause a great deal of damage. Moreover, everything is on a slightly different orbit. That means, over time, these orbits can cross.

And the longer something remains in orbit, the greater the odds that these paths will eventually cross, and that things will smash together. Some of the things which are floating around in space include two cameras that got away from astronauts, players, a screwdriver, a wrench, a full tool bag, garbage bags, a lens cap, a spatula, and microscopic flakes of rocket propellant.

And that is on top of all the rocket debris and dead satellites. If a ship with astronauts were to be hit, it could lead to the deaths of the crew. If an important satellite were to be hit, it could lead to a loss of critical communications, GPS signals, or observational capabilities. This isn't just a theoretical problem. There have been cases of collisions in space.

The space shuttle had many tiny impacts from debris in space. On the 7th Space Shuttle mission in 1983, the front windshield was hit by a fleck of paint, which damaged the window. It looked very similar to what happens when a rock hit your windshield. Damage to the shuttle's heat tiles was so common that they eventually began flying the shuttle backwards in space so that the engines, which weren't used during re-entry, took most of the damage.

The shuttle endeavor was hit by an object so large that its radiator looked like it was hit with a bullet. The International Space Station has to move, on average, at least once a year, to avoid space debris. The Soviet Cosmos 1275 satellite was hit by an object in 1981, which was believed to be the first case of a satellite being destroyed by space junk. Perhaps the worst case occurred in 2009, when the Cosmos 2251, satellite, which was dead, smashed into the Arridium 33 satellite at a relative speed of 26,000 miles per hour. These collisions, and there have been several more, only make things worse. In the first case, 300 new objects were created from the collision, and in the second, there were suddenly thousands of new objects thrown off on different trajectories in orbit. In 2007, the Chinese

government did an anti-satellite missile test that blew up a satellite in space, creating tens of thousands of pieces of debris. This problem of junk causing collisions, which then creates exponentially more junk, risk something called the Kessler syndrome. This was hypothesized in 1978 by NASA scientist David Kessler. He proposed that collisions could start a cascade of debris, which would cause more collisions and even more debris rinse and repeat. If it was bad enough, it would lender low-earth orbit, which is where the majority of satellites operate and where all current manned missions take place, totally unusable for generations. To top it all off, the problem has been getting worse, not better over the last 10 years,

as more satellites have been put into orbit. So, what can we do? For starters, most satellites now have some sort of decommissioning plan. That means they carry enough fuel to force the satellite into reentry at the end of its life, or some other mechanism to cause it to come back into the atmosphere and burn up. For example, Elon Musk, SpaceX has put close to 1,000 satellites in orbit for their Starlink Internet constellation. Each satellite, while small, has a small thruster to do small maneuvers of the satellite and to deorbit it at the end of its lifespan. One company called Tethers Unlimited has created a very simple device, which they call Terminator tape.

It's a long, thin, 70-meter tether that can extend from a satellite to increase its drag, causing the satellite to re-enter the atmosphere years or decades sooner than it otherwise would. Most satellites in low-earth orbit now have some sort of deorbiting strategy. But what about all the stuff that's up there already? One proposal is just to send up a big tug with lots of propellant. It could move from orbit to orbit, rendezvousing with dead satellites, swallowing them up, and then when it's full, it would just de-orbit itself and everything inside of it. Other proposals involve sending up tiny satellites to meet dead satellites

and having them latch on and then deorbiting them. But what about the really small stuff? Nothing has been done yet, but there are many ideas. One Singaporean company wants to send up a giant solar-powered electromagnet. It would either get the debris to attach itself to the magnet or alter its orbit enough to hasten its natural re-entry. Another proposal is to launch a giant foam ball that would expand once it was in a vacuum.

The ball would then passively smash into objects, either embedding them in the foam or slowing them down enough that they would deorbit faster. Another proposal would fire a high-powered laser from the Earth's surface at space debris. By heating the object, especially a very small object, the radiating heat would cause the debris to change its orbit, again, hastening the time it would take to re-enter the atmosphere.

Other proposals involving harpoons and nets have been suggested as well. Along the various technical solutions, there also needs to be an international treaty governing space debris. Right now, there isn't anything that legally deals with the problem. There would need to be a ban on anti-satellite tests in orbit like the Chinese did in 2007, as well as a requirement that any satellite which is put into orbit has a built-in mechanism for deorbiting. Over the next 10 years, the number of satellites in orbit is expected to quintuple. There will be more satellites launched than there were between Sputnik and now. The issue of space debris is only going to become more important.

If we are to avoid a Kessler syndrome type event, which would render parts of Earth orbit dangerous, if not unusable, efforts will be needed to solve this problem quickly. Executive producer of Everything Everywhere Daily is James McAlla. The associate producer is Thor Thompson. Remember to leave a five-star review to get your review read on the show. They can be left at Apple Podcasts, Podcasts, or wherever you listen to the show. Also, you can help support the show over at patreon.com. Patrons can get merchandise like t-shirts and hoodies, as well as having direct access to provide suggestions for future episodes.