Vly News - Professional news Platform

For the first time in nearly 5,000 years of observation, researchers have fully cataloged the optical illusion created in the sky when light shines through ice crystals known as atmospheric halos. The detailed ‘inventory’ of atmospheric halos often looks at atmospheric optical illusions from known sources and explains rarer halos, including those whose origins remain a mystery. Halos are caused by the accumulation of water ice crystals smaller than 10 micrometers in the atmosphere. The qualities of these atmospheric illusions, such as their color or whether they have white arcs, spots or rings, are determined by the shape and orientation of the ice scattering from and the path that light takes towards these crystals. Often, the type of crystal behind the scattering can be identified by the shape of the halo they create. Related: What makes Earth’s atmosphere so special? This atmospheric illusion has been documented by mankind since at least the Babylonian era — which began around 189

Rapid bursts of radio waves from millions to billions of light-years away can be used as probes to study the halos of the hard-to-see hazy gas that surrounds closer galaxies. These pulses, known as fast radio bursts (FRBs), slow down as they transit through the gas shrouding the galaxy between their source and Earth. This has the added consequence of their radio frequency scattering. Using this to investigate the galaxy’s gaseous halo, researchers from the California Institute of Technology (Caltech) found twice as much matter as previously believed in the envelope surrounding the galaxy. This has implications for how this collection of stars and planets evolves over long periods of time. Astronomers looked at a sample of 474 distant FRBs with the Canadian Hydrogen Intensity Mapping Experiment (CHIME) which confirmed that the 24 FRBs intercepted by the galactic halo did indeed slow down compared to the others that traveled to Earth unimpeded. Thus, this effect can be used to investi