China’s FC-31 is a twin-engine stealth fighter demonstrator, which includes two iteratively different flying airframes that have been under active flight test since late 2012 and late 2016, respectively. This aircraft has often incorrectly been dubbed the “J-31” and been given various other names over the years, such as “J-21.” None of these J-designations remain true to the aircraft’s current state. It is a self-funded technology demonstrator from Shenyang Aircraft Corporation (SAC) and AVIC rather than a project being actively developed by the People’s Liberation Army (PLA). Therefore the names “J-31” or “J-21” are incorrect.
However, for the last few years it has been accepted that the PLA Navy has selected an FC-31-derived airframe to be developed into its carrier-based fifth-generation fighter, resulting in an aircraft that will indeed receive a J-designation. The PLA watching community has often referred to this aircraft as “J-35”; however, such a designation would be quite a numerical jump from “J-20” and thus deviate from prior norms where aircraft designations were somewhat more sequential (see, J-10, J-11, J-15, J-16, all as fourth-generation fighters). It also seems rather on the nose, having the same number as the U.S. F-35. It goes without saying there is substantial room for confusion over this aircraft’s name alone.
By Paul Voosen
Several years ago, workers breaking ground for a power plant in New Zealand unearthed a record of a lost time: a 60-ton trunk from a kauri tree, the largest tree species in New Zealand. The tree, which grew 42,000 years ago, was preserved in a bog and its rings spanned 1700 years, capturing a tumultuous time when the world was turned upside down—at least magnetically speaking.
Radiocarbon levels in this and several other pieces of wood chart a surge in radiation from space, as Earth’s protective magnetic field weakened and its poles flipped, a team of scientists reports today in Science. By modeling the effect of this radiation on the atmosphere, the team suggests Earth’s climate briefly shifted, perhaps contributing to the disappearance of large mammals in Australia and Neanderthals in Europe. “We’re only scratching the surface of what geomagnetic change has done,” says Alan Cooper, an ancient DNA researcher at the South Australian Museum and one of the lead authors of the study.
The speedy approach used to tackle SARS-CoV-2 could change the future of vaccine science
When scientists began seeking a vaccine for the SARS-CoV-2 coronavirus in early 2020, they were careful not to promise quick success. The fastest any vaccine had previously been developed, from viral sampling to approval, was four years, for mumps in the 1960s. To hope for one even by the summer of 2021 seemed highly optimistic.
But by the start of December, the developers of several vaccines had announced excellent results in large trials, with more showing promise. And on 2 December, a vaccine made by drug giant Pfizer with German biotech firm BioNTech, became the first fully-tested immunization to be approved for emergency use.