Clues Emerge in Mystery of Flickering Quasars
Some of the universe's most luminous objects have disappeared much faster than expected
Stories by Shannon Hall
Earth's Tectonic Activity May Be Crucial for Life--and Rare in Our Galaxy
A new study finds plate tectonics may be hard to sustain on exoplanets
What to Believe in Antarctica's Great Ice Debate
Although not all the studies agree, most climate scientists argue that, yes, Antarctica is losing mass in a warming world
Ravenous Supermassive Black Holes May Sterilize Nearby Planets
A new study sheds light on how damaging black holes can be to the habitability of planets throughout the Milky Way and the universe
Found: Thousands of Man-Made Minerals--Another Argument for the Anthropocene
Future geologists will find thousands of human-made minerals in the ruins of our civilization
Volcanic Eruption May Have Plunged the Maya into a "Dark Age"
A new study of ancient ash links an El Chichón eruption to a time of inexplicable cultural upheaval in Maya history
Celestial Cartography Is in the Midst of a Dramatic Upgrade
A new map of the Milky Way will improve understanding of stellar physics—and ultimately of our galaxy’s entire history
Numbers Cruncher: Why Trump's Win Blindsided the Big Polls
Changing technology and fickle humans are pushing art into the science of aggregating surveys
Upcoming Galaxy Map Could Radically Transform How We See the Milky Way
The Gaia spacecraft’s new chart may drastically improve our understanding of the physics of stars, and ultimately of our galaxy’s entire history
Hellish Venus Might Have Been Habitable for Billions of Years
A team of astronomers think the torrid and toxic world was once a cozy home for potential life
A Volcano Might Be Brewing under Rome's Suburbs
Testing the limits of predictions, some geologists say long-silent Colli Albani might be starting a new eruption phase
LIGO Discoveries Will Help Scientists Run Stellar Autopsies on Colliding Black Holes
Now that astronomers have detected gravitational waves, they are seeking the origins behind the black hole duos that give rise to them
Underwater "Lost City" Built by Microbes?
Geologists find that ancient underwater structures off Greece were likely created by methane jets and bacteria
Which Came First on Earth--Habitability or Life?
One astronomer suggests that we cannot necessarily disentangle the two
Will Moose Thrive or Die Because of Climate Change?
The animals are expanding northward as the Arctic heats up, yet new diseases of a warmer world are taking a toll
Gravitational Waves from Black Hole Megamergers Are Weaker Than Predicted
A search for low-frequency “hums” from supermassive black holes comes up empty
![A River Once Ran through the Sahara [Graphic]](https://static.scientificamerican.com/sciam/cache/file/3E02FD91-F565-41E6-BF9E7850D6786340_agenda.jpg?w=275&h=154&fit=crop)
A River Once Ran through the Sahara [Graphic]
In full flow it would rank 11th among the largest rivers today
Earth Is Tipping Because of Climate Change
Melting ice and shifting rain patterns are causing the north and south poles to drift
Martian Mile-High Mounds Mystery: The Answer Is Blowing in the Wind
Mountains thrusting from Red Planet crater floors were probably dug by billion-year breezes
Mysterious Gravitational Tug on Saturn May Help Find Planet Nine
Astronomers are homing in on the whereabouts of a hidden giant planet in our solar system, and could discover the unseen beast in roughly a year