China’s LAIRD radar with 5900 mile range detects plasma bubbles over Giza

For the past few years militaries around the world have been trying to figure out how to detect and track hypersonic weapons, and recently I talked about a breakthrough that used sensors to detect the plasma streams rippling around them. And now, in what could be seen as an unrelated breakthrough – but that could actually be pivotal to the Chinese achieving this capability at distance – Chinese researchers have used the country’s powerful Low-Latitude, Long-Range Ionospheric Radar (LARID), located on Hainan Island, to detected plasma bubbles above the Midway Islands and - perhaps more ominously - the pyramids of ancient Egypt.

But let’s just get this out of the way right off the bat: it’s not aliens.

Instead, these well-known space weather anomalies are called Equatorial Plasma Bubbles (EPBs), and they occur in the region of the Earth’s atmosphere known as the Ionosphere. Here, the Sun’s UV light knocks electrons loose from atoms, forming a diffuse layer of ions extending from 50 to 400 miles above the surface. However, sometimes, pockets of density irregularities form in the ionosphere and lead to a depletion of ions, which can significantly impact radio and satellite-based communication.

On August 27, the Institute of Geology and Geophysics - a part of the Chinese Academy of Sciences - announced that LARID detected these plasma bubbles during a solar storm back in early November of 2023. With a detection range of nearly 6,000 miles, LARID can detect these bubbles as far as Hawaii in the east or Libya in the west by blasting high-powered electromagnetic waves into the ionosphere, which can then bounce along vast distances.

If this powerful wave encounters a bubble - which can sometimes grow to a couple hundred miles in diameter - the wave reflects and is then received by a suite of transceiver antennas.

This is a much different technique for tracking these anomalies than NASA’s. The agency relies on the Global-scale Observations of the Limb and Disk (GOLD) mission - basically a satellite appendage attached to a commercial satellite - to track potential EPBs across the Earth. While GOLD often detected bubbles during periods of intense disturbance, such as solar storms and volcanic eruptions, the mission detected bubbles during relatively quiet atmospheric moments as well and showcased that there’s much more to learn about these mysterious bubbles.

The South China Morning Post originally reported the story and veered into the radar’s potential military applications: “Due to its low resolution, LARID cannot be used to detect military targets such as aircraft or warships. However, according to reports from official Chinese media, over-the-horizon military quantum radar and satellite systems using similar technologies have been widely deployed by the Chinese military and have detected targets including F-22 stealth fighter jets. Signals emitted by over-the-horizon radars have wavelengths that reach several metres, making it difficult for stealth coatings on aircraft to absorb them, and some new Chinese warships, such as the 055-type destroyers, are also equipped with radars capable of detecting stealth aircraft in a similar manner.”

However, our scientific understanding of these bubbles is still lacking, as different techniques in tracking them only tell us certain details about the phenomenon. So, while China’s LARID system might show some sort of military promise, its potential benefit to science could even surpass any battlefield advantage.