Talk about the EmDrive has been swirling around for some years and it's never far from controversy or rumor. Now, in the latest chapter of its strange story, Chinese scientists say they are making more and more progress on this "impossible engine".

The video (below) recently aired on the state-owned China Central Television (CCTV2). It appears to show an interview with Dr Chen Yue, one of China’s leading researchers working on the EmDrive, and other engineers at the China Academy of Space Technology. Although most of the technicalities of the thruster are not discussed in the video, it reportedly mentions progress on their “reactionless” thruster.

The EmDrive is often dubbed the "impossible engine”. It’s a proposed type of electromagnetic thruster that generates thrust without needing a propellant by bouncing microwaves around in a closed container. Unlike conventional engines that expel mass to produce thrust, the EmDrive uses only electricity to generate movement. Most controversially, that means it appears to be producing a reaction without the need for an action, violating Newton’s third law.

For the purposes of space exploration, it could be an absolute game changer. Much of the cost of space exploration and satellites is the launching process. In theory, this method of propulsion holds the potential to reduce these overheads, have higher payloads, and a longer satellite lifespan. It also opens up the possibility of journeys to Mars in just 70 days. Nevertheless, these are huge promises and many critics still dismiss the EmDrive as “junk science”, claiming that something else must be acting as the propellant.

The reactionless thruster was originally hypothesized by British scientist Roger Shawyer in 2001. It has since been worked on by NASA engineers, with a peer-reviewed paper recently published on the science behind the engine. That was considered a huge step forward in the development of the hypothesized thruster. However, for the time being, China appears to be leading the way.

In December 2016, China's space agency claimed they were testing out an EmDrive in space on their Tiangong-2 satellite. Odd bits of information about China’s work on the thruster pops up every so often in the Western media, however just like the EmDrive in general, many are skeptical about China's claims about their progress with the technology.