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In the galaxy II Zw 40, dust (shown in yellow) is strongly associated with clusters of stars (shown in orange). UCLA researchers have used new observations of this galaxy to confirm that these stars are creating enormous amounts of dust. Image via UCLA.

Star clusters seen spewing out dust

UCLA astronomers confirm that stars are responsible for producing dust on a galactic scale, a finding that’s consistent with long-standing theories.

Artist's conception of the Spiderweb. In this image, the protogalaxies are shown in white and pink, and the blue indicates the location of the carbon monoxide gas in which the protogalaxies are immersed. Image via ESO/ M. Kornmesser/ NRAO.

Astronomers see giant galaxy being born

The Spiderweb Galaxy – which spans some 3 times the diameter of our Milky Way – is forming inside a cluster of protogalaxies, in a dense soup of molecular gas.

Image via NASA

Mystery of sun’s coronal heating

Exploding “heat bombs” might explain why the sun’s upper atmosphere, or corona, sizzles at millions of degrees – hundreds of times hotter than at the surface.


It’s a bird, a plane, the tiniest asteroid!

Asteroid 2015 TC25 is small enough to be straddled by a person, reminiscent of the iconic bomb-riding scene in the movie Dr. Strangelove. It swept between us and the moon a year ago.

A mile-wide (1.4 km) crater on the rim of a larger crater near Mars' equator, as seen from CaSSIS. Image via University of Bern.

First images from ExoMars mission

A camera on board ESA’s ExoMars mission has returned its first images from orbit. It was meant to be a test, but the images are spectacular.

Comparison of an ultra-diffuse galaxy with the nearby Andromeda galaxy, an ordinary spiral galaxy and our Milky Way's nearest large neighbor.

Supernovas and ultra-diffuse galaxies

These strange galaxies have 1,000 times fewer stars than the Milky Way, yet occupy a large space. Astronomers used an advanced computer simulation to show that supernova explosions helped create them.

The Hubble Space Telescope captured this view of colorful stars in our Milky Way galaxy when it pointed its cameras towards the constellation Sagittarius the Archer. Image via IAU.

IAU approves 227 star names

The International Astronomical Union – which has given itself responsibility to name and define things in space – has now joined the rest of us in recognizing traditional star names.


How long to orbit Milky Way’s center?

One journey of our sun and planets around the center of our Milky Way galaxy is sometimes called a cosmic year. That’s approximately 225-250 million Earth-years.


Vast underground water ice on Mars

Water ice can’t persist on Mars surface in the region of Utopia Planitia, about halfway from Mars’ equator to its pole. But researchers say there’s water in a vast frozen lake underground.

Cassini will soon begin a series of 20 orbits that fly high above and below Saturn's poles, plunging just past the outer edge of the main rings. Image via NASA JPL/ Caltech/ Space Science Institute.

Saturn spacecraft prepares to ring-graze

On November 30, the Cassini spacecraft will begin a series of 20 orbits that fly high above and below Saturn’s poles, plunging just past the outer edge of the main rings.


GoPros go to edge of space

Photog Adventures sent its GoPros to space, captured some stunning views, and then lost the cameras for 15 days. Follow the adventure in this video.

Satellite galaxies associated with the Milky Way Galaxy. Squares are Large and Small Magellanic Clouds and circles are dwarf spheroidal galaxies. Via suburutelescope.org.

New record-breaking Milky Way satellite

It’s record-breaking because it’s so faint. Could this galaxy be a sign of many yet-unknown dwarf galaxies orbiting our Milky Way? And do we now have a way to detect them? Astronomical theorists hope so!

The Vela supercluster in its wider surroundings. Image via Thomas Jarrett (UCT).

A new major supercluster of galaxies

The Vela supercluster had gone unnoticed due to its location behind the plane of the Milky Way, where dust and stars obscure the view.


What happens if the sun disappears?

Some things that would happen here on Earth if our giant source of heat and light were to vanish from the sky, and how long it would take.


Great Valley found on Mercury

Scientists have discovered a Great Valley on Mercury, hundreds of miles long and sunken by as much as 2 miles (3 km) below the surrounding terrain.

Image Credit: NASA/JHUAPL/SwRI

A slushy ocean beneath Pluto’s heart?

A bulging, viscous, liquid ocean may lie beneath Pluto’s heart-shaped Tombaugh Regio. If it exists, it solves a longstanding puzzle about this region.

Sun halo captured on June 6, 2016 by Amy Gray in Aiken, South Carolina.

Why a halo around the sun or moon?

A large ring or circle of light around the sun or moon is called a 22-degree halo by scientists.

Asteroid collision, via the AIM mission.

100 scientists say yes to asteroid mission

Scientists have signed an open letter in support of increased knowledge of Near-Earth Objects (NEOs), whose orbits carry them near Earth. You can sign it, too.


Super effect on us from a supermoon?

A supermoon’s pull of gravity creates higher-than-usual tides. But gravity doesn’t affect a human body as much as it does an ocean tide.

Sun's path through the zodiac.

What is the zodiac?

The zodiac is defined by 12 constellations that lie along the annual path of the sun across the sky.