The Big Bear Solar Observatory (BBSO) is an exceptional site, and its Goode Solar Telescope (GST) is a great instrument. Thanks to a new upgrade that pushes it to its theoretical limit, that special instrument has just become even better. The telescope has now delivered the clearest views of fine structures within the solar corona, the vast and extremely hot atmosphere of the Sun.
The solar corona is a major mystery. Its temperature is in the millions of degrees, hundreds of times hotter than the surface below. The process that creates this bizarre discrepancy is not fully understood, and only recently developed ways to observe the Sun have provided enough clues to explain what might be going on.
The solar corona is also where the solar wind is produced, and many events happening there affect space weather across interplanetary space.
As such, it is crucial to have the best view of the corona possible, and now the GST can do that thanks to a new adaptive optics system that compensates for the blurring caused by the Earth’s atmosphere. One of the results of that compensation is a stunning video of coronal rain, condensed plasma falling back towards the Sun.
“The turbulence in the air severely degrades images of objects in space, like our Sun, seen through our telescopes. But we can correct for that,” Dirk Schmidt, Adaptive Optics Scientist at the National Solar Observatory, who led the development, said in a statement.
“Adaptive optics is like a pumped-up autofocus and optical image stabilization in your smartphone camera, but correcting for the errors in the atmosphere rather than the user’s shaky hands,” added BBSO Optical Engineer and Chief Observer, Nicolas Gorceix.
Adaptive optics has become common in night-time astronomy over the last two decades or so, and has even been applied to solar telescopes looking at the surface – but there were challenges to adapting it to a system designed to look at the edge of the Sun. The atmosphere of the Earth has been a major limiting factor, not allowing resolutions of the corona to less than 1,000 kilometers (621 miles). This resolution was achieved 80 years ago.
“The new coronal adaptive optics system closes this decades-old gap and delivers images of coronal features at 63 kilometers resolution—the theoretical limit of the 1.6-meter Goode Solar Telescope,” explained Thomas Rimmele, NSO Chief Technologist, who built the first operational adaptive optics for the Sun’s surface.
Similar to a new 8K resolution approach used on the Vacuum Tower Telescope (VTT), this brand-new technology might soon be used on telescopes across the world to get the best possible views of the Sun.
The study is published in Nature Astronomy.
Source Link: Watch Plasma Raindrops Falling Back On The Sun In Incredible New Video
