ScAm - 09.2019

2 Scientific American, September 2019

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Lonely Planets

It has been 30 years since the Voyager  2 spacecraft flew by Neptune,

which like its planetary sibling Uranus is an “ice giant” world in the

outer solar system. Now some scientists are contemplating a return.

Go to http://www.ScientificAmerican.com/sep2019/lonely-planets

ON THE WEB

4 From the Editor

6 Letters

8 Science Agenda

Everyone is an agent in the new information

warfare. By the Editors

10 Forum

Disabilities make us better scientists.

By Gabi Serrato Marks and Skylar Bayer

12 Advances

Ancient creatures traveled. Making a perfect

crepe. A fern’s fronds filter arsenic. Robot cluster.

22 The Science of Health

Vitamin megadoses and the risk of fractures.

By Claudia Wallis

24 Ventures

Apple’s amazing new screen delivers.

By Wade Roush

96 Recommended

How opium has poisoned our world. Femicide

in Tijuana. Quantum mechanics revealed.

By Andrea Gawrylewski

97 The Intersection

Shaky medical info from the Web.

By Zeynep Tufekci

98 Anti Gravity

Best become comfortable with the unknown—

it’s not going anywhere.^ By Steve Mirsky

99 50, 100 & 150 Years Ago

100 Graphic Science

Does obesity shorten lives? By Alberto Cairo

96

12

8

ON THE

COVER

For the cover and

inside pages of this

special issue, we

asked the artists at

Red Nose Studio to

‰³l_ ̧³_ßxîxÿCāä

to illustrate the

abstract themes

of truth, lies and

ø³_xßîCž³îāÍ ̧ß

the illustrations on

pages 28, 48 and 72,

the artists took

inspiration from

îšxäCāž³îšCî ̧³§ā

“fools and children

îx§§îšxîßøîšÍÚ

Illustration by

Red Nose Studio.