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Your online destination for news articles on planets, cosmology, NASA, space missions, and more. You’ll also find information on how to observe upcoming visible sky events such as meteor showers, solar and lunar eclipses, key planetary appearances, comets, and asteroids.

Thursday, August 25, 2016

Astronomers find a galaxy thats mostly dark matter

The hazy oval isn’t glare on your screen; it’s an entire galaxy. Dragonfly 44 weighs about the same as our Milky Way, except it’s 99.99% dark matter and has less than a hundredth the number of stars. Dark matter is stuff that can&rs...

Massive, short-lived stars may still form like the Sun

The elusive, gigantic blue O-type stars form fast (10 to 100,000 years fast), die young, and do both those things well. But when it comes time to study the stars, that becomes a big problem for astronomers because their massive size makes them blow u...

When does a small star become a brown dwarf?

While the brightest stars can be easy to identify, their cooler cousins can be challenging to distinguish from the wannabes that never managed to reach stellar status. The difference can be huge when planets are involved, as with the three worlds orb...
Wednesday, August 24, 2016

Is Proxima Centauri b the most promising exoplanet yet?

A pale red dot not far from our sun may be orbited by a pale blue dot much different than Earth. In a shocking find, astronomers Wednesday announced their discovery of an Earth-sized planet orbiting the nearest star, Proxima Centauri, just 4.2 light-...
Friday, August 19, 2016

The Sky This Week for August 19 to August 28

Friday, August 19 • You’ll want to keep your eyes on the western evening sky all week. A trio of bright planets — Mercury, Venus, and Jupiter — lurk low in the twilight, forming an elegant triangle that changes shape with each...
Wednesday, August 17, 2016

A dormant white dwarf violently exploded out of its slumber

White dwarf-companion star binaries can have explosive relationships. They begin with a hibernation phase, where the companion sends a whisper of mass to the white dwarf as a stream of hydrogen. The white dwarf cyclically brightens and dims and then ...
Tuesday, August 16, 2016

MACHOs may be out of the running as a dark matter candidate

A recently discovered ultra-faint dwarf galaxy is sending astronomers clues about the makeup of dark matter in the neighborhood of the Milky Way. It is one more clue that a type of stellar object called massive compact halo objects (MACHOs) are proba...

Will the real culprit behind Mars' gullies please stand up?

This post also appears on the Planetary Society's website. Martian gullies were in the spotlight recently thanks to a NASA press release stating they were "likey not formed by liquid water." The release concerns the publication of a new paper by Nu&...
Monday, August 15, 2016

Black holes can still shine a bright light, astronomers say

Black holes aren’t perfectly black. For the first time, using a model of a black hole that traps sound instead of light, scientists have seen spontaneous evidence of what comes out of them. These particles are so few and faint that it’s ...

The best view of the Perseids may have been from the ISS

For many people the finest Perseid meteor shower in 20 years was obscured by clouds — curse you atmosphere! But for the lucky crew aboard the International Space Station, viewing conditions are always perfect — they just look down instea...

Meet the woman who got America into orbit in the trailer for 'Hidden Figures'

This week, olympians Simone Biles and Simone Manuel reminded Americans of the incredible accomplishments of our black women. In 1962, Americans were awed by the work of another black woman as astronaut John Glenn orbited the earth three times and ret...
Friday, August 12, 2016

Was Venus once ripe for life?

It's hard to imagine now, but hellish Venus may once have had balmy temperatures and shallow seas. Even with Venus' much slower rotation rate, it may have even looked a whole lot like Earth. Of course, that's gone now. In a paper published in Geophys...

This object may open up new solar system mysteries

There are plenty of weird objects in our solar system, but the newly discovered trans-Neptunian object (TNO) Niku might be one of the weirdest. It's not the composition of Niku that makes it strange. It seems to be a chunk of ice about 124 miles (20...


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