Researchers have identified a growing threat to astronomy from the sunlight reflecting off communication devices in space. One such device, a communication satellite called BlueWalker 3, is currently one of the brightest objects visible from Earth, matching the brightness of Procyon and Achemar, two of the brightest stars in the night sky.

“BlueWalker 3 is visible in both dark sky and urban skies, though in urban settings this will be limited to when BlueWalker 3 passes overhead,” said Dr. Jeremy Tregloan-Reed, a co-author of the study at the University of Atacama in Chile. “Large constellations (星座) of bright artificial satellites in low Earth orbit pose significant challenges to ground-based astronomy,” the study’s authors wrote.

Tregloan-Reed said a large reflective brightness means that when a satellite crosses the detector of a telescope, it leaves a mark that can be difficult, if not impossible, to remove. This could lead to loss of data from the affected pixels (像素). But he said space-based astronomy also faced challenges from such satellites, noting that observations by the Hubble telescope had increasingly been affected by marks from Starlink satellites. Besides, the team notes the radio frequencies used by BlueWalker 3 are close to those used for radio astronomy, raising the possibility that such satellites could cause interference.

While BlueWalker 3 was folded when it was launched last year, once in space it opened up to reveal a huge surface area that reflected sunlight. Tregloan-Reed added that even if all the reflective brightness of all satellites was reduced to below the level visible by the naked eye, “the sky background glow will increase due to the accumulative effect of having hundreds of thousands of satellites from various operators from many countries in low Earth orbit. It is disastrous!”

BlueWalker 3, built by AST Space Mobile, is just the first one to be launched. The company is planning a constellation of satellites nicknamed BlueBirds, consisting of over 100 similar satellites and aimed to provide satellite network service for the whole world. You can imagine how bright the night sky will be at that time!

On a rainy day, the raincoat and the umbrella have been necessary for people toprotect themselves from the rain for centuries. However, Chinese designers are tryingto challenge that with an new product called an “umbrella raincoat".

As the name suggests,this wonderful rainwear design combines the raincoat and the umbrella. For starters, it looks kind of strange, and sellers on Chinese websites actually list this fact as the only disadvantage(缺点）of the product. They actually describe it a little differently —You will get 100% rate of second glances( —瞥）” —you actually know what it means. Also, like the umbrella, it only protects your upper body from the rain, with the lower body and legs being almost completely exposed(暴露）. However, it does free up both your hands, which is actually the main advantage of wearing an umbrella raincoat.

“But isn’t the classic raincoat just better?” I hear you asking. Well, not if you want to show off your dresses while still enjoying some protection from the rain. Even those clear raincoats become foggy in the rain，making it hard for passers-by to admire your fancy dresses, however, with the umbrella coat, they still have a clear view. Other advantages include a lightweight Voidable(可折叠的）design, two straps that keep it from being blown away by strong winds.

The umbrella raincoat comes in all kinds of sizes and colors, and if the online stores who are going to sell it are believers, it will soon replace the traditional umbrella, and go into the houses of hundreds of millions of families. But believe it or not, I think it will play a key role in people’s everyday life.

If this thing had been invented in America, I wouldn't have bothered writing about it. Those guys come up with something strange every day _T but it turns out that China has a taste for them, too.