The Darkest World: Scientists Discover ‘Darth Vader’ Planet

The distant exoplanet TrES-2b, shown here in an artist's conception, is darker than the blackest coal. It refuses to give back light. Why? That's a mystery

The polarities of darkness and light have been central to human cultural imaginings since our origins.

In the 5th century B.C. there was Zoroastrian religion, based on the eternal battle between darkness (evil) and light (spiritual purity). In the modern world we have the mythic conflict between Luke Skywalker in his white tunic and his black-shrouded, fallen father, Darth Vader. Given our penchant for pulling the world apart into this kind of dichotomy, it is, perhaps, no wonder that the recent discovery of the darkest of dark planets has made news.

A few weeks ago, two astronomers announced the discovery of TrES-2b via the Kepler spacecraft. The planet is a so-called “Hot Jupiter” — a large gas giant orbiting extremely close to its sun-like star (the whole system is about 750 light years away from us).

What makes TrES-2b so remarkable is its refusal to give back light. The scientific word for reflectivity is albedo. The Earth reflects about 37 percent or 0.37 of the light it receives from the sun. That is why we present such a beautiful bright blue face to the universe.

TrES-2b is another story entirely. It bounces back less than 1 percent (0.01) of the light it receives from its star. That means the planet is blacker than coal. Seen from space, TrES-2b would barely be visible.

It is not clear yet why TrES-2b is so dark. It may be that the intense heat from the nearby star has formed strange, light-absorbing compounds in the planet’s atmosphere.

“It’s a mystery as to what’s causing it to be so dark,” co-discover David Kipping told Space.com. “There’s a good chance it’s a chemical we haven’t even thought of yet.”

A world darker than coal, darker than night and darker than the heart of wickedness. You can provide your own metaphor, analogy or back story if you want.

One of the great beauties of science is the way it lets us discover how much richer the world is than our imagination might have conceived. Then our imaginations find their own uses for these discoveries, making the world we find our own.

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What Age Is The Moon? It Could Be Waning…

the full moon rises behind the ancient temple of Posseidon (AP Photo/Petros Giannakouris)


WASHINGTON (AP) — That old moon might not be as antique as we thought, some scientist think. They say it’s possible that it isn’t a day over 4.4 billion years old.

But other astronomers disagree with a new study’s conclusions. They think the moon is up to its typical age-defying tricks and is really pushing 4.6 billion as they have suspected all these years.

Either way, the new analysis of an important moon rock brought back by the Apollo 16 mission is showing that the moon isn’t ready to give up its true age and origins quite yet, even though scientists thought they had it all figured out a decade or two ago.

“It’s not as ancient as we might think,” said study chief author Lars Borg, a geochemist at the Lawrence Livermore National Lab. His study appears online Wednesday in the journal Nature.

The study uses new techniques and radioactive isotopes of lead and other elements to date the moon rock at 4.4 billion years old. What’s key is that this is a special type of rock that would have floated up to the moon’s crust soon after its theorized ocean of molten rock cooled. That supposedly happened soon after the moon formed as a result of a spectacular crash between Earth and a planet. The chunks that broke off formed the moon.

That means there are two possibilities, Borg said. Either the moon is 200 million years younger or the accepted theory of a molten rock ocean on the moon is wrong, he said.

Borg acknowledges that some moon rocks have been dated at nearly 4.6 billion years old. But those conclusions could be wrong because of weaker rock dating techniques used in the past, he said.

Outside scientists said Borg did good work coming up with a date for the Apollo 16 rock but may have jumped to the wrong conclusion on lunar age or origins. They said it’s possible that the rock is from a smaller molten rock ocean or was created when the moon was bombarded by space debris which was much more common a few billion years ago.

Borg’s conclusion “is a little bit fancy for my taste,” said Erik Asphaug of University of California, Santa Cruz, who recently published a theory that Earth used to have a second smaller moon until it crashed into the bigger one.

MIT astronomer Maria Zuber called the study in Nature “very puzzling.”