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Christmas Gift Guide

Snug with its star

View from another Earth

Searching the skies

A shorter path

Water world?

Not the brightest star in the sky

The VLT in action

Rocky and warm

What finding a new planet looks like

HARPS spectrograph

Map to our new neighbor

Small star, big discovery

The size of two suns in the sky

Proxima b spotters

Astronomers have discovered an "Earth-like" planet orbiting Proxima Centauri, the nearest star to Earth besides our own sun. The planet, dubbed Proxima b, orbits nearly five times closer to the red dwarf than Mercury does to our sun. Because Proxima Centauri is much smaller and cooler than our sun, the rocky planet is still in the habitable zone where water and life could theoretically exist. Click through for more views and details on one of the most significant space discoveries since the first exoplanet around a sun-like star, 51 Pegasi b, was confirmed in 1995.

Caption by / Photo by Ricardo Ramirez and James Jenkins (Department of Astronomy, Universidad de Chile)

This is an artist's rendition of the surface of Proxima b with Proxima Centauri on the horizon. The nearby star Alpha Centauri AB can also be seen to the upper right.

Caption by / Photo by ESO/M. Kornmesser

The European Southern Observatory's 3.6-meter La Silla telescope can be seen in the top of this composite. It was one of the instruments used to confirm the presence of a habitable-zone planet around Proxima Centauri at the lower right -- shown next to an image of the double-star Alpha Centauri AB.

Caption by / Photo by Y. Beletsky (LCO)/ESO/ESA/NASA/M

This slide illustrates how much closer the orbit of the planet around Proxima Centauri (Proxima b) is compared with the orbit of Mercury around our sun.

Caption by / Photo by ESO/M. Kornmesser/G. Coleman

Another rendering shows Proxima b facing Proxima Centauri. The planet is likely tidally locked to its star, which means the same side is always facing the star.

Caption by / Photo by ESO/M. Kornmesser

The bright star in this image of the night sky is Alpha Centauri AB. Proxima Centauri is the much fainter red dwarf star nearby.

Caption by / Photo by Digitized Sky Survey 2 Acknowledgement: Davide De Martin/Mahdi Zamani

A shot of the European Southern Observatory's Very Large Telescope (VLT) during observations. The yellow line is a "laser guide star," part of an adaptive optics system that compensates for the blurring of Earth's atmosphere. The VLT was used for observations of Proxima Centauri over the years.

Caption by / Photo by ESO/S. Brunier

Proxima b is a little more massive than Earth, but it orbits very close to its star, with years that last less than two weeks.

Caption by / Photo by Nature video screenshot by Eric Mack/CNET

A chart of the Doppler shifts that indicated Proxima Centauri was "wobbling," indicating the presence of a nearly Earth-size planet in close orbit.

Caption by / Photo by ESO/G. Anglada-Escudé

The HARPS spectrograph seen during laboratory tests. The ESO instrument was used to help confirm the existence of Proxima b. The vacuum tank is open so some of the high-precision components inside can be seen.

Caption by / Photo by ESO

This chart shows the large southern constellation of Centaurus (The Centaur), providing a map for future generations to travel to the nearest exoplanet. Proxima Centauri is too faint to see in the night sky without using a small telescope.

Caption by / Photo by ESO/IAU and Sky & Telescope

Proxima Centauri is comparatively small to many other stars and even planets.

Caption by / Photo by ESO

Proxima Centauri would appear much larger in the sky to someone on Proxima b than our sun does to us from Earth, despite being a smaller star. This is because of how close the planet orbits.

Caption by / Photo by ESO/G. Coleman

The ESO's 3.6-meter telescope and the Swiss 1.2-meter Leonhard Euler Telescope in this image are planet-spotting heavyweights that helped identify Proxima b.

Caption by / Photo by Iztok Bončina/ESO
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