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News
7
Departments
2 EDITOR’S NOTE
4 NOTEBOOK
Giant clams use acid to
tuck into reefs; painted
ladies fly far
28 REVIEWS & PREVIEWS
A conservation biologist
explains our intimate
connection with bees
30 FEEDBACK
32 SCIENCE VISUALIZED
Daguerreotypes come
out of the dark
Features
16 A Galaxy’s Ecosystem
COVER S TORY New tools offer a chance
to explore the tumultuous clouds that
surround — and control — the Milky Way
and other galaxies. By Lisa Grossman
22 The Clean Cycle
Lack of sleep may contribute to Alzheimer’s
disease by robbing the brain of the time it
needs to wash away sticky proteins.
By Laura Beil 16
COVER Gas flows out
from M82, the Cigar
galaxy, to its invisible
circumgalactic medium in
this Hubble image. NASA,
ESA, Hubble Heritage Team
6 Modified poliovirus
extends the lives of some
brain cancer patients
Fewer teens are having sex
7 New ape species is found
in an ancient crypt
8 Robots course correct by
reading people’s thoughts
Communication cables
could do double duty as
earthquake detectors
9 Pillars of Creation stand
tall with magnetism
10 Alzheimer’s plaques may
be the brain’s way of
fighting off herpesvirus
and other invaders
Domestication shrunk
bunnies’ brains
11 Narcolepsy research
yields a clue to addiction
12 NASA spacecraft will get
up close and personal
with the sun
13 Mars crusted over
quickly
14 Turning on genes is not
a one-protein job
15 News in Brief
Clearest snapshot yet of
the Zika virus exposes
vulnerabilities
How coffee helps
protect the heart
Solar system visitor is
an impostor
Einstein’s theory of
general relativity passes
another test
4
SOCIET Y UPDATE
The latest headlines from
Science News for Students
