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Why no eclipse every full and new moon?

This year, in 2017, there are 12 full moons and 12 new moons, but only four eclipses – two lunar and two solar.

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.

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.

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.

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.

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.

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.

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.

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?

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?

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.

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.

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.

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.

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.

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.

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.

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.

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.

Dwarf planet Makemake has a moon

This Hubble Space Telescope image reveals the first moon ever discovered around little Makemake, in the outermost region of our solar system.