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How Are Exoplanets Detected?

Astronomers detect exoplanets through transits, stellar wobble, direct imaging, microlensing, astrometry and timing signals, then use follow-up observations to rule out…

What Are Meteor Showers and What Causes Them?

Meteor showers happen when Earth passes through streams of small particles left along the orbits of comets or, in some cases, asteroid-like bodies. The particles enter t…

What Are the Northern Lights and Why Do Auroras Happen?

Auroras occur when energetic charged particles are guided by Earth's magnetic field into the upper atmosphere, where collisions with oxygen and nitrogen produce light. T…

What Is a Black Hole and How Do Black Holes Form?

A black hole is a region where matter has been compressed so strongly that, inside a boundary called the event horizon, escape would require moving faster than light. Bl…

How Does a Fusion Reactor Work?

A fusion reactor aims to create a hot plasma in which light nuclei fuse, confine or compress that plasma long enough to release useful energy, then capture the energy in…

What Can Exoplanet Atmospheres Tell Us?

Exoplanet atmospheres can reveal molecules, temperatures, clouds, circulation and clues to a planet’s formation, climate and possible habitability by imprinting chemical…

What Is the Nearest Exoplanet to Earth?

Proxima Centauri b is the nearest confirmed exoplanet to Earth known today, orbiting Proxima Centauri a little more than four light-years from our solar system.

How Do Astronomers Detect Exoplanets?

Astronomers usually detect exoplanets indirectly, by measuring how a planet changes the light, motion, or gravitational behavior of its host star.

The latest images of galaxies spiraling together.

The Gemini North telescope, located atop Maunakea in Hawaii, USA, has discovered interacting spiral galaxies approximately 60 million light-years away in the constellati…

Mysterious lights hovering in the night sky have left many people bewildered.

A strange phenomenon was observed by many residents in the sky near San Diego on the evening of June 27th.

How many years would it take to explore the universe while traveling at the speed of light?

The speed of light, equivalent to 299,792,458 m/s, is considered the maximum speed limit revealed by Einstein's theory of relativity.

12 'unbelievable' inventions of Nikola Tesla

Video: Aurora Borealis and meteor shower appear simultaneously

The combination of the aurora borealis and the Perseid meteor shower is a rare and spectacular event that leaves many sky enthusiasts in awe.

At 250 million light-years in diameter, how massive is the Boötes void?

The Boötes void or giant void is a very large, nearly spherical region containing very few galaxies. It is located in the vicinity of the constellation Boötes.

How is the age of the universe calculated?

The universe is about 13.8 billion years old, but how do we know that?