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Discover

Discover November 2019

Discover Magazine will amaze you, enlighten you, and open your eyes to the awe and wonder of science and technology. Discover reveals secrets, solves mysteries, and debunks old myths. Discover shares new findings and shows you what makes our universe tick.

:
United States
言語:
English
出版社:
Kalmbach Publishing Co. - Magazines
刊行頻度:
Monthly
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この号

1
test, and test again

I’ll never forget sitting in physics class, riveted by the next challenge from Mr. Price. He reveled in getting us to visualize in our minds what’s happening when a pendulum swings or a loaded spring bounces back. He pushed us to understand the underlying equations, and then, with his infectious enthusiasm, launched us on experimentation. As someone who struggled in math classes, I loved the simultaneous abstraction and groundedness of physics. One story in this issue, for me, is kind of like being back in that physics class. Frequent Discover contributor Adam Hadhazy takes us on a romp through 10 experiments, from the third century B.C. to the mid-1900s, that changed the very nature of how we understand the world today. Most of them were successful, but even toss in that…

2
print feedback

Swimming on Air (July/August 2019) “Everything Worth Knowing: Flight” by Jonathon Keats notes that the Archaeopteryx likely used its wings similarly to the butterfly stroke of a swimmer, but states the purpose of the vertebrae running through the tail and the asymmetrical tail feathers remains a mystery. Having once been a competitive swimmer, I think the answer to the purpose of the Archaeopteryx’s tail seems obvious — it used it like a swimmer’s dolphin kick. A swimmer uses two dolphin kicks to every one butterfly stroke with the arms. Why couldn’t the Archaeopteryx do the same to propel it through the air? It could also turn the tail slightly to direct the flight’s direction and, when soaring, the tail could be used to aid in ascending and descending, just like modern birds…

1
web feedback

Back to the Moon Vice President Mike Pence announced March 2019 that the Trump administration wants to put humans back on the moon within five years. The mission would focus on the moon’s South Pole, which remains relatively unexplored. But with NASA’s financial setbacks and the current political climate, it might be more wishful thinking than anything. We asked our fans on Facebook: Do you want to see the U.S. return to the lunar surface? Mellanie Nelson Robles: I want investments in schools and crumbling infrastructure, I want a Green New Deal — so many issues have a higher priority! Francesk Nikolli: Everyone is saying that the money can be spent better on health departments or other things on Earth, and they’re right. But this kind of research is also for a better world: By…

1
the crux

SMART SLIME No, it’s not a Rorschach inkblot: This image captures two single-celled organisms having a chat. Individual members of Physarum polycephalum, which in nature clump together by the thousands to form a slime mold, can share information about their environment via veinlike networks. While researchers have long known that the collective slime molds can learn to avoid irritants, such as salt, they didn’t know how. But a recent study showed that a single P. polycephalum will actually absorb some of a potentially problematic substance and hang onto it like a souvenir — and use its venous networks to warn other cells to steer clear.…

3
nature’s jump drive

IN THE LATE 1990S, geneticists began studying extinct species’ DNA, analyzing hair and bone preserved in frozen tundra. At that time, most computers stored data on floppy disks that held just 1.44 megabytes of memory — smaller than the average selfie. Today, those disks might as well be Ice Age artifacts, too. Not only is their storage capacity miniscule by today’s standards, but recovering their data is practically impossible, due to the degradation of their materials and the special equipment required to read them. The floppy disk encapsulates some of the greatest long-term challenges to computer science. According to Microsoft principal researcher Karin Strauss, future storage will need exponentially greater density to hold the data we produce as electronic devices become a greater part of our lives. Plus, long-term archiving will…

2
dragon races

SARA ZAHENDRA AND KENT MCFARLAND helped discover something that entomologists had long suspected: Green darners, a species of dragonfly, are nomads at heart. Working with colleagues, the pair, both biologists at the Vermont Center for Ecostudies, found that some green darners zoom hundreds of miles north in the spring, seeking breeding grounds with fewer rivals and predators. Others, hatched in the north, zip south in the fall to escape the cold. The key to unlocking the insects’ birthplace was a chemical signature lifted from their wings. But before the researchers could decode this critical clue, they had to catch some dragonflies. Zahendra and McFarland led that effort and, relying heavily on volunteers, ultimately rounded up 852 dragonflies. Here, Zahendra describes their first collecting trip in 2012, at Newnans Lake in Florida. IN HER…