Galaxies

A dwarf galaxy near the Milky Way may consist of more dark matter than regular matter.* Clara Moskowitz reports

The Planck satellite reveals the universe's first stars formed more than a hundred million years later than previously believed

Today is Valentine’s Day. In love? Or just the opposite? Express how you feel with physics-inspired Valentines—and anti-Valentines for those who perhaps aren’t huge fans of the holiday.

Astronomers have discovered variable stars that periodically dim and brighten at frequencies close to the famed golden mean

Some natural phenomena need few words to explain why they’re fascinating. Eclipses, transits, and phases in astronomy tend to fall into that category.

The crew of STS-51-L: Front row from left, Mike Smith, Dick Scobee, Ron McNair. Back row from left, Ellison Onizuka, Christa McAuliffe, Greg Jarvis, Judith Resnik.

Intriguing data from an event in 2007 hints at an exomoon forming around a giant planet in a youthful star system 420 light years from Earth.

In 1990, NASA's Voyager 1 spacecraft briefly looked back from its journey out of the solar system, capturing a view of the faraway Earth. Carl Sagan called it the "pale blue dot." From more than 6 billion kilometers away, beyond the orbit of Pluto, it seemed remarkable that our planet was even visible.

I’ve always been an Edgar Allan Poe fan, so much so that I even watched the horrifying—not in a good way–2012 film The Raven.

I remember battling sleepiness as I slouched in a large lecture hall, squinting to make out the writing on the blackboard during my freshman introductory physics course in college.

One of our galaxy’s arms may do a full 360, upping the chances that our galactic home is a rare cosmic beauty

NASA's planet-hunting Kepler spacecraft finds two worlds that have sizes and orbits similar to ours