SpaceX Is Using Starlink To Make Low Earth Orbit Safer For Everyone
Space is filled with garbage. More specifically, the low Earth orbit, where most satellites and space equipment spend their time. NASA estimates that there are nearly 6,000 tons of material in low Earth orbit. The European Space Agency gives similar numbers, stating that over the course of 60 years of space activities, it has resulted in about 56,450 tracked objects in orbit, with 28,160 still there and being tracked by the US Space Surveillance Network. That debris poses a threat to future space exploration missions because it can result in collisions or damage to passing craft, but also to objects already in orbit, like satellites we use for communication and other information gathering. It gets even worse year after year with more launches and more debris left behind. There really hasn't been an answer to the problem besides avoiding it whenever possible, until now.
SpaceX is launching the Stargaze Situational Awareness System (SSA), a technology designed to enhance the safety and sustainability of low Earth orbit operations. More importantly, SSA's screening data will be available for free to the broader satellite operator community.
The important bit is that Stargaze will significantly increase detection capabilities for orbiting debris and objects thanks to more rapid polling — SpaceX estimates "continuous observations" at approximately 30 million transits daily across a fleet of 30,000 star trackers. Conventional ground-based systems only track a limited number of times per day and are plagued by other challenges, like volatile space weather, making debris very difficult to keep an eye on.
Starlink ephemeris — tables of trajectories for astronomical objects — will be shared every hour throughout the day. That will help other satellite operators track debris, use the information to avoid collisions and risky events and essentially make Earth's orbit safer. But there's another potential benefit here.
With Stargaze in operation, we may be able to remove or reduce some of the debris
It turns out, researchers and tech experts have actually proposed ways to remove and eliminate the debris in low Earth orbit. One company called Astroscale Japan has developed a small satellite, the ADRAS-J, which will capture space junk. Another team of researchers proposed a solution using a plasma propulsion system to remove debris, which would drop it out of orbit, forcing it to burn up in the atmosphere. One big problem with both of these ideas, and likely others, is that space debris has been incredibly difficult to track.
SpaceX's Stargaze could be the solution to that problem, allowing teams to better track debris in near real-time, or more accurately, at the very least. That would, in turn, allow for more precise estimations to capture it and dispose of it, using whatever methods are in play.
Stargaze has been available as a closed beta to select "participating satellite operators" but will soon open up to all satellite operators willing to submit data. That also implies researchers working on similar projects should be able to access the relevant ephemeris. We won't know for some time if that actually helps reduce space junk and debris, but for now, it's great news that SpaceX is making the SSA available to a broader community, and for free.