Something is heading toward Earth, and scientists have no idea WTF it is.
What we know: WT1190F is apparently man-made. It is relatively small. It will likely incinerate in the atmosphere during re-entry, with any remaining chunks depositing somewhere near the coast of Sri Lanka.
What we don't know: Where it comes from.
It's probably not the Event Horizon returning home, nor is it particularly dangerous. According to the ESA, the agency's Near-Earth Object Coordination Centre will be closely monitoring what the object, which they believe is a "discarded rocket body" that usually orbits the planet once every three weeks.
"The first goal will be to better understand the reentry of satellites and debris from highly eccentric orbits," NEOCC astronomer Marco Micheli said on the ESA's website. "Second, it provides an ideal opportunity to test our readiness for any possible future atmospheric entry events involving an asteroid, since the components of this scenario, from discovery to impact, are all very similar."
The U.S. is monitoring WT1190F as well as part of a much larger surveillance system designed to prevent any surprises in space.
"Joint Functional Component Command for Space's Joint Space Operations Center (JSpOC) operates the Space Surveillance Network," Air Force Capt. Nicholas J. Mercurio, JSpOC's director of public affairs, told Mic. It's a "sophisticated architecture of ground- and space-based radar and electro-optical sensors which enables us to track upwards of 23,000 man-made objects in space daily." Once the objects are identified with high enough clarity, researchers post the data online.
"We are aware of the object in question, but due to its inclination and orbit, the JSpOC doesn't have sufficient screening data from our sensors to catalog the object for inclusion in the space catalog," Mercurio added. "Without the ability to accurately screen the object at this time, we are unable to confirm what it is or perform a reentry prediction."
So WTF is this thing? Of the 23,000 man-made objects orbiting Earth, 1,300 are active payloads, Mercurio said, meaning they're still powered and in use (like a spacecraft or satellite, for example). Mercurio noted the surveillance network is "taking upwards of 400,000 observations per day," resulting in an average of 23 alerts per day. In 2014, satellites moved 121 times to avoid collisions using the data.
Capt. Mercurio did not offer any theories on what WT1190F was, telling Mic, "We don't speculate."
Ultimately, scientists want more of these objects to fall out of the sky — and burn up in the process. Earlier this year, Space.com reported on space agencies' work building a Coherent Amplification Network laser that would vaporize parts of space debris and send it hurtling back toward the atmosphere, clearing out potentially dangerous hazards to spacecraft.