There May Be a Ninth Planet (And It’s Not Pluto)

Caltech astronomer Michael Brown has proposed the existence of a ninth planet, the existence of which would explain the strange orbits of six KBOs. 
Jupiter with moons, Europa and Io.

The Art of Observing Weather on Distant Planets

Exoplanetary meteorology enables scientists to determine weather patterns on planets too far for direct observation. 
Extreme ultraviolet light streams out of an X-class solar flare

The Threat of Solar Flares

Solar flares are highly unpredictable and difficult to anticipate. But their threat is very real.
Bacteria

Protecting Mars From Earthly Contaminates

Now that water has been discovered on Mars, the next step is to ensure we don't contaminate the planet with Earthly microbes and bacteria.
This is an artist’s impression of a Kuiper Belt object (KBO), located on the outer rim of our solar system.

Next stop for the New Horizons Spacecraft: The Kuiper Belt

New Horizons, the NASA probe deployed to visit Pluto, has begun a new mission: visit the Kuiper belt, a region beyond the orbit of Neptune.
Credit: NASA/JPL/University of Arizona
Caption: Alfred McEwen

The Canals of Mars

We now know there's liquid water on Mars, according to NASA. But at the turn of the 20th century, we believed something else: that Mars had canals.

The Extinct Civilization of Mars

Liquid water has been detected on Mars. We explore the history of the search, and the astronomer, Percival Lowell, who shook the public imagination.
Astronauts on the International Space Station are ready to sample their harvest of a crop of "Outredgeous" red romaine lettuce from the Veggie plant growth system that tests hardware for growing vegetables and other plants in space.
Credits: NASA

Gardening in Space

Zero-gravity gardening: why growing plants in space isn't the same as here on Earth.
Artist's concept of buckyballs and polycyclic aromatic hydrocarbons around an R Coronae Borealis star rich in hydrogen. Credit: MultiMedia Service (IAC)

What’s Between the Stars? Buckyballs!

How buckyballs fit into the formation of new stars.

Kepler Finds Truly Earth-like World

The Kepler telescope discovers a habitable planet.