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Capricorn-Large

Capricornus? Here’s your constellation

The constellation Capricornus the Sea-goat. How to see it, and how a sea-goat came to reside among the stars.

Image via Hawai'i Volcanoes National Park

More than 450 volcanoes in Ring of Fire

The Pacific’s Ring of Fire has 75% of the world’s active and dormant volcanoes, plus it’s prone to powerful earthquakes. Here’s why.

Image Credit: Luz Adriana Villa A.

Can you tell me the full moon names?

For both the Northern and Southern Hemispheres, full moons have names corresponding to calendar months or seasons of the year.

We’re on the hunt for life – what do we do when we find it? Image credit: NASA/JPL-Caltech/MSSS

Do no harm to life on Mars? Ethical limits of Prime Directive

A philosopher argues that now is the time to figure it out, before we make the inevitable discovery of extraterrestrial life.

Classical illustration of the constellation Virgo the Maiden, via constellationsofwords.com

Virgo? Here’s your constellation

The constellation Virgo the Maiden fully returns to the early evening sky – with her feet planted on the eastern horizon – by early May.

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Old under-ice volcanoes on Mars

An oddly textured region of southern Mars is not ice-covered today. Yet landforms here – and now certain minerals – are associated with under-ice volcanoes.

This artist's concept depicts select planetary discoveries made to date by NASA's Kepler space telescope. Image credit: NASA/W. Stenzel

Kepler confirms 1,284 new planets

The announcement more than doubles Kepler’s confirmed exoplanets and suggests that, somewhere out there, we’ll discover another Earth.

Artist's conception of Planet Nine, in the far outer solar system. In this image, the star in the lower right is our sun. Image via Caltech/R. Hurt (IPAC)

Why Planet 9 shouldn’t exist

Earlier this year, scientists presented evidence for a Planet Nine in the far outer solar system. Scientists think it exists, but – if so – how did it get there?

Photo Credit: NASA

What is the sun’s proper name?

You’ve no doubt heard star names such as Polaris or Betelgeuse. But what about our star? Does the sun have a name, and if so what is it?

Comet Halley's position in May, 2016. The view is from the north side of the solar system, whereby the planets orbit the sun in a counterclockwise direction - but Halley's Comet orbits the sun clockwise. Click here for Comet Halley's present position, or if you'd like, change the date to view its position in any chosen year.

Comet Halley, parent of 2 meteor showers

The Eta Aquarid meteor shower was spawned by the famous Comet Halley. But Halley spawned another meteor shower, too.

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This date in science: First American in space

Alan Shepard became the first American in space on May 5, 1961. His suborbital flight took place just three weeks after the Soviet Union’s Yuri Gagarin orbited Earth once.

Sunlight glints off of Titan's northern seas this near-infrared, color mosaic from NASA's Cassini spacecraft. Image credit: NASA/JPL/Univ. Arizona/Univ. Idaho

A pure methane sea on Titan

We knew that Saturn’s moon Titan had seas and lakes of liquid hydrocarbons, but their exact composition was unknown until recently.

Imagined view from the surface of one of the newly discovered planets, with ultracool dwarf star TRAPPIST-1 in the background. Image credit: ESO/M. Kornmesser

Just 40 light-years away, 3 potentially habitable planets

Earth-like planets aren’t exclusively orbiting sunlike stars. Ultracool dwarf star TRAPPIST-1 hosts 3 potentially habitable planets.

Artist's impression of the unique object C/2014 S3 (PANSTARRS). Observations with ESO’s Very Large Telescope, and the Canada France Hawai`i Telescope, show that this is the first object to be discovered that is on a long-period cometary orbit, but that has the characteristics of a pristine inner Solar System asteroid. It may provide important clues about how the Solar System formed. Because the object has spent most of its life away from the inner Solar System it suffered very few collisions, and its surface displays few or no craters. As it formed in the same region as the Earth did, it is mostly rocky, and therefore has only very limited cometary activity.

Orbit like a comet, rocky like an asteroid

They’re calling it a Manx comet, after the cats with no tails. It may have formed in the inner solar system and been ejected outward.

View larger. | As January, 2016, opens, there are four planets in the predawn sky.  Ben Zavala caught them on January 4, 2015.  Thanks, Ben!

Astronomical events in 2016

A month by month listing of major moon phases, conjunctions, oppositions, meteor showers and other important dates, from astronomer Fred Espenak.

Hydrothermal system at the Danakil Depression. The yellow deposits are a variety of sulphates and the red areas are deposits of iron oxides. Copper salts colour the water green. Image credit: Felipe Gomez/Europlanet 2020 RI

Inhospitable Danakil Depression hosts extreme life

It’s below sea level, with near-boiling water bubbling up from underground, high salt concentrations and toxic vapor. Yet life survives here.

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How long to travel to Alpha Centauri?

Read about star travel via conventional propulsion, warp drives, and more.

Image taken from the Mastcam on NASA's Curiosity Mars rover shows the rugged surface of the Naukluft Plateau, plus upper Mount Sharp at right and part of the rim of Gale Crater. Image credit: NASA/JPL-Caltech/MSSS

Mars rover crosses most rugged terrain so far

The Curiosity rover has nearly crossed a stretch of the roughest terrain it’s seen during its 44 months on Mars. Scientists are monitoring the wear and tear on the rover’s wheels.

Jan Oort. Copyright Leiden Observatory. Used with permission.

This date in science: Jan Oort’s birthday

Visualize a vast reservoir of icy comets on the outskirts of our solar system. That’s what Jan Oort did in 1950, and why the Oort Cloud bears his name.

Image credit: NOAA

Does this jellyfish look like a spaceship, or what?

Video of a spectacular jellyfish that floated past NOAA’s ROV on April 24, 2016 in the Mariana Trench – the deepest oceanic trench on the planet.