Yes, there really is a lot of space junk

This visualization shows the 15,723 objects being tracked in low-Earth orbit by the U.S. military's Joint Space Operations Center — including nearly 13,000 that are classified as space debris.

Data: Space-Track; Note: Perigee is the point in an object's orbit where it's closest to Earth. Chart: Lazaro Gamio/Axios

Why it matters: As space opens up to more nations, companies and possibly nonprofits, concerns are growing about how to track the growing amount of debris. This week, Vice President Mike Pence announced a "comprehensive space traffic management policy" to address the issue.

"The magnitude of the problem is unquantified. We can’t put a solid risk on it [for satellite operators]. But we all know it is only going to get worse."
— Moriba Jah, University of Texas at Austin

"There's a lot of ambiguity about what is up there and where it will be an hour from now, tomorrow or next week," says Jah, who's building a database in hopes that it will lead to "[global] rules of the road for good behavior" in space.

Two challenges: Jah says the resolution for tracking objects is currently on the order of kilometers, and "most of the things up there aren’t transmitting their information."

The bigger picture: The military's public database "account[s] for only 4% of the objects in space, according to AGI, a company which provides software to commercial and government entities to analyze and track objects," per CNBC.

Notable: 2,842 of the roughly 3,800 objects in low-Earth orbit associated with China are from Fengyun 1-C, a weather satellite launched in 1999. China used it as a target for a missile test in 2007, spewing fragments throughout space.

The details: In low-Earth orbit, the overwhelming majority of objects are pieces of satellites, rocket bodies and boosters, and other human-made objects-turned-debris. And that doesn't include bits and pieces that are too small to track but are still potentially damaging.

The data: is a collection of data from the Joint Space Operations Center, which tracks objects orbiting Earth in order to screen for potential collisions.

Go deeper: Business Insider's Dave Mosher writes on the threat posed by space junk.