A new, thin-lensed telescope design could far surpass James Webb– goodbye mirrors, hello diffractive lensesAlmost all space telescopes, including Hubble and Webb, collect light using mirrors. Our proposed telescope, the Nautilus Space Observatory, would replace large, heavy mirrors with a novel, thin lens that is much lighter, cheaper and easier to produce than mirrored telescopes. Because of these differences, it would be possible to launch many individual units into orbit and create a powerful network of telescopes.Existing telescopes can detect exoplanets as small as Earth. However, it takes a lot more sensitivity to begin to learn about the chemical composition of these planets. Even Webb is just barely powerful enough to search certain exoplanets for clues of life – namely gases in the atmosphere.Conventional lenses use refraction to focus light. Refraction is when light changes direction as it passes from one medium to another – it is the reason light bends when it enters water. In contrast, diffraction is when light bends around corners and obstacles. A cleverly arranged pattern of steps and angles on a glass surface can form a diffractive lens.
Over the following two years, our team invented a new type of diffractive lens that required new manufacturing technologies to etch a complex pattern of tiny grooves onto a piece of clear glass or plastic. The specific pattern and shape of the cuts focuses incoming light to a single point behind the lens. The new design produces a near-perfect quality image, far better than previous diffractive lenses.Using the new technology, our team thinks it is possible to build a 29.5-foot (8.5-meter) diameter lens that would be only about 0.2 inches (0.5 cm) thick. The lens and support structure of our new telescope could weigh around 1,100 pounds (500 kilograms). This is more than three times lighter than a Webb–style mirror of a similar size and would be bigger than Webb’s 21-foot (6.5-meter) diameter mirror.The lenses have other benefits, too. First, they are much easier and quicker to fabricate than mirrors and can be made en masse. Second, lens-based telescopes work well even when not aligned perfectly, making these telescopes easier to assemble and fly in space than mirror-based telescopes, which require extremely precise alignment.
Finally, since a single Nautilus unit would be light and relatively cheap to produce, it would be possible to put dozens of them into orbit. Our current design is in fact not a single telescope, but a constellation of 35 individual telescope units.
Each individual telescope would be an independent, highly sensitive observatory able to collect more light than Webb. But the real power of Nautilus would come from turning all the individual telescopes toward a single target.
Italian uproar over judge's 10-second groping ruleDoes it count as sexual harassment if an assault lasts less than 10 seconds?
Many young people in Italy are expressing outrage on social media, after a judge cleared a school caretaker of groping a teenager, because it did not last long enough.
The case involves a 17-year-old student at a Rome high school.She described walking up a staircase to class with a friend, when she felt her trousers fall down, a hand touching her buttocks and grabbing her underwear.
"Love, you know I was joking," the man told her when she turned around.
A Rome public prosecutor asked for a three-and-a-half year prison sentence but this week the caretaker was acquitted of sexual assault charges. According to the judge, what happened "does not constitute a crime" because it lasted less than 10 seconds.
Forget About Hiding From Climate Chaos in AmericaLINCOLN, Vt. — The capital of Vermont — the state that often tops those “best states to move to avoid climate change” lists — was, until Tuesday afternoon, mostly underwater.The receding water sloshing in our streets was ferried by storm tracks from fast-warming seas 1,000 miles south. The storm dumped four to nine inches of rain on towns up and down the Green Mountain State, where the ground was already saturated.For each degree Celsius of warming, the atmosphere holds 7 percent more water vapor, driving the extreme precipitation events in New England that have increased by 55 percent since 1958, according to the Fourth National Climate Assessment.There is pulling ticks — which recently expanded their empire into my high, cold piece of Vermont, courtesy of warming winters — off my daughters almost weekly.Our infrastructure wasn’t built for these extremes, for this pace of change. Neither were our prevailing risk models. Just two weeks ago, researchers from the First Street Foundation warned in a new study that the database that the National Oceanic and Atmospheric Administration uses to estimate the risk of extreme rainfall events is being outpaced by climate change and is in urgent need of updating. Americans can now expect to experience “once in a hundred year” rain events at 20-year intervals, on average. And the trend won’t stop there: That interval will keep shrinking, thanks to unchecked fossil fuel burning.
The weather is always changing. We take climate change seriously, but not hysterically. We will not adopt nutty policies that harm our economy or our jobs.*
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