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An artist's conception of the star LkCa 15 and the nearby protoplanet. (Credit: Karen L. Teramura, UH IfA)

Planets form from disks of swirling material that condense into solid bodies. Once only a theory, this formation has now been caught in the act by scientists using telescopes at the W.M. Keck Observatory in Hawaii (a site that should be familiar if you’ve read the Smithsonian story on black holes). The planet’s name is LkCa 15 b and researchers say it’s a protoplanet (below, in blue), still surrounded by cool dust and gas (in red). “We…found a planet, perhaps even a future solar system at its very beginning,” says the University of Hawaii’s Adam Kraus, lead author of the study that will appear soon in the Astrophysical Journal.

The planet LkCa 15 b appears in blue surrounded by cooler dust and gas in red, near the star LkCa 15. (Credit: Kraus & Ireland, 2011)

Kraus and his co-author, Michael Ireland of Australia’s Macquarie University, made their discovery by combining two techniques to cancel out the light from bright stars. The first is adaptive optics, which uses powerful computers to rapidly manipulate the telescope’s mirrors and adjust for distortions caused by Earth’s atmosphere. The second is aperture mask interferometry, and it further improves the resolution of the telescope. “We can manipulate the light and cancel out distortions,” Kraus says. They pointed the telescope at the star LkCa 15, canceled out the star’s light and there it was, a newly forming planet.

“LkCa 15 b is the youngest planet ever found,” Kraus says. “This young gas giant is being built out of the dust and gas….For the first time, we’ve been able to directly measure the planet itself as well as the dusty matter around it.”

Phil Plait, at Bad Astronomy, has more details:

The disk’s hole is about 8 billion km across. Disks like this are seen around other stars, and it’s generally thought that the hole is caused by a planet orbiting inside that region sweeping up material. In this case, that looks to be true! If the planet is in a circular orbit, it’s about 2.5 billion kilometers from its star, a little closer to its star than Uranus is from the Sun (it’s not known if the orbit is circular or elliptical; that’ll take a few years of observations as the planet physically moves around the star and the orbit can be calculated). The planet is much hotter than you might expect, but that’s because it’s so young: material is falling onto it, heating it up. That’s why it’s glowing in the infrared.

…Nothing like this has been seen before in a planet so young! That’s scientifically quite important. Our models of how planets form are complex, and we need detailed observations to see if the models are correct or not. Since planet formation is a process, we need observations of it at different stages, including very early on. That’s crucial, since it represents the transition period between the time before planets start to form in the disk, and the time when the planets are all finished and tidied up. We’ve seen both of those before, so this observation is a first.

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The Very Large Array in New Mexico (via wikimedia commons)

The Very Large Array, a collection of 27 radio antennas out in New Mexico, has a problem—it has a boring name. That hasn’t stopped the thousands of scientists who have used the array since 1980 from making observations of our universe. But with an expansion of the array on schedule to be completed next year, the National Radio Astronomy Observatory, which runs the array, has decided that it’s time for a change.

“Though the giant dish antennas, the unique machines that move them across the desert, and the buildings on New Mexico’s Plains of San Agustin may appear much the same, the VLA truly has become a new and different facility. We want a name that reflects this dramatically new status,” says NRAO director Fred K.Y. Lo. “The new name should clearly reflect the VLA’s leading role in the future of astronomy, while honoring its multitude of past achievements.”

Those achievements include: receiving radio communications from the Voyager 2 spacecraft as it flew past Neptune; key observations of Sgr A*, at the center of the Milky Way, now known to be a black hole; discovery of the first Einstein Ring; as well as contributions to many other investigations of stars, galaxies, black holes and other astronomical phenomena.

In addition, the Very Large Array has often appeared in pop culture, a perfect stand-in whenever a mysterious telescope might be needed in movies such as Contact, Armageddon and Transformers: Dark Side of the Moon. You may even have gotten the mistaken idea that the VLA conducted searches for SETI from the movie Independence Day.

There are several ways to go when naming a telescope. Name it after a famous person in astronomy, like the Hubble, or after a place, like Arecibo. Acronyms are always a favorite in science, like CARMA. Or you could be more creative and go in a different direction, perhaps making up something based on a future goal (the Planet Finder 9000?) or a dream.

If you’ve got an idea for what to rename the VLA, tell us in the comments below and also submit it here by 23:59 PST, December 1, 2011. The winning name will be announced at the American Astronomical Society meeting in Austin, Texas on January 10, 2012.

A combined image from the Chandra and XMM-Newton X-ray observatories of RCW 86, which was determined to have started out as SN 185 (Credits: ESA/XMM, NASA/CXC, University of Utrecht (J. Vink))

Astronomers are getting a bit of a treat this week—they’re watching a supernova exploding 21 million years ago (that is, 21 million light years away) in the Pinwheel Galaxy. That’s pretty close for a supernova (they’re usually around a billion light years away), and you might even be able to see it with a simple pair of binoculars. But what was the first supernova?

OK, that was a trick question. We can’t know what was the first star to explode. But we can look at the first recorded supernova, SN 185.

In 185 A.D., someone in China looked up in the night sky and saw a new star. It sparkled and did not move, so it couldn’t be a comet. This “guest star” stayed in the sky for eight months and then disappeared forever; it was recorded in the Book of the Later Han, which told the history of China from 25 to 220 A.D.

The guest star was a supernova, a star that had run out of fuel and then collapsed in on itself in a thousandth of a second. The core of the star heated to a billion degrees and destructive gamma rays were produced. Neutrinos were generated in huge quantities. Only a tiny fraction were absorbed by the stellar gas, and they had so much energy they ripped apart the outer layers of the star. This violent explosion, which could have been brighter than an entire galaxy, also produced X-rays, gamma rays and ultraviolet light. The resulting shock wave produced radioactive elements such as cobalt and titanium. Any planet too close to such a destructive event would have been torched.

In 2006, scientists using the Chandra X-ray Observatory and the XMM-Newton Observatory determined that the supernova remnant RCW 86 was the leftover bits of SN 185. They calculated how fast the energized shell of the remnant was moving to estimate the original date of the supernova and determined that the star had gone supernova about 2,000 years ago. Scientists had thought RCW 86 might be SN 185 because the remnant’s location matched historical records of the supernova, but previous calculations gave the remnant an age of 10,000 years. It appears those calculations were based on measurements of a part of the shock wave that had encountered a region of dense matter and slowed down.

An artist's concept of what planet TrES-2b might look like (Credit: David A. Aguilar (CfA))

A planet orbiting a star some 750 million light years away is extraordinarily dark, according to astronomers at the Harvard-Smithsonian Center for Astrophysics and Princeton University who report their findings in the Monthly Notices of the Royal Astronomical Society. They used data from NASA’s Kepler spacecraft to study the alien world and found that it reflects only 1 percent of the light that reaches it.

The planet, TrES-2b, is a gas giant about the size of Jupiter. But that’s where the similarities end. Jupiter is cool enough to be surrounded by bright clouds of ammonia that reflect a third or more of the sunlight that falls on it. TrES-2b is much hotter—more than 1,800 degrees Fahrenheit—and lacks the reflective clouds. It’s atmosphere is full of chemicals that absorb light, such as gaseous titanium oxide and vaporized sodium and potassium, which explain, in part at least, the planet’s dark nature. The planet is so dark, it is blacker than anything in our Solar System, blacker than paint, blacker than coal.

“It’s not clear what is responsible for making this planet so extraordinarily dark,” says study co-author David Spiegel of Princeton University. “However, it’s not completely pitch black. It’s so hot that it emits a faint red glow, much like a burning ember or the coils on an electric stove.”

TrES-2b is weird in another way—it is tidally locked, like our Moon is with Earth, so that one side always faces its sun, the star GSC 03549-02811, and one side always faces away.

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We haven't had a message from ET yet, but maybe we're not looking in the right way. (courtesy of flickr user Robin Hutton)

The search for intelligent life in the universe took a hit earlier this year when SETI had to put the Allen Telescope Array on hiatus due to lack of funding. (It now appears that SETI may soon raise enough money to get the ATA up and running again.) But then, there’s a good chance that this approach, based on the idea that somewhere in the universe alien civilizations are sending radio messages directed at Earth, may be completely misguided. “In my opinion,” Arizona State University astronomer Paul Davies writes in his book The Eerie Silence, “this ‘central dogma’ simply isn’t credible.” He points out that if even a fairly close civilization, say 1,000 light years away, were to look through a telescope and find Earth, it would see the planet 1,000 years in our past. Why would they bother to send a message to a planet that hadn’t even discovered electricity, let alone built a receiver for such a message?

If listening for radio messages is a bit of a long shot, how else could we go about it? Here are 10 ideas that have been put forth, and even put into practice, by various sources (and if you want more detail, I recommend Chapter 5, “New SETI: Widening the Search,” of The Eerie Silence):

1 ) Optical SETI: Russian and American scientists have been searching the skies periodically for the last couple of decades looking for laser light, which is not only distinguishable from other natural types of light, such as starlight, but could only be produced by an intelligent source.

2 ) Look for huge alien structures: When people bring this one up, the best example is always the Dyson sphere, a hypothetical structure that a civilization would build around an entire star to capture all of its energy.

3 ) Find evidence of asteroid mining: Humans are already looking at the asteroids in our solar system and considering their potential for mining, so why wouldn’t an alien civilization do the same? Evidence could include changes in the chemical composition of the asteroid, the size distribution of debris surrounding it, or other thermal changes that could be detected from Earth.

4 ) Check planetary atmospheres for pollutants: If there are non-natural chemicals, such as chlorofluorocarbons, in a planet’s atmosphere, it’s a sign that there might be someone with technology on the ground.

5 ) Look for signs of stellar engineering: For now, this is the stuff of science fiction, but a civilization capable of tinkering with a star would surely be of interest to us Earthlings.

6 ) Look for an alien artifact here on Earth: Earth has been around for billions of years—who says that aliens haven’t been here before? If they visited long ago, perhaps they left behind something in a difficult-to-reach spot, such as at the bottom of the ocean.

7 ) Find a pattern in neutrinos: Davies points out in his book that neutrinos, those ghostly subatomic particles, are probably better suited for bringing a message over a long distance than either radio or optical signals. A message would have to be simple—transmitted in a sort of alien Morse code—but we could detect it here on Earth.

8 ) Check for a message in DNA: DNA is just another way to encode information. Aliens, or even just an alien probe, could have visited Earth long ago and inserted a message into some ancestral creature. Of course, there are several hurdles to such an idea, as Davies notes—getting the message here, getting it into a critter, keeping it from getting destroyed by mutations over perhaps millions of years—but it certainly an intriguing possibility.

9 ) Find a propulsion signature from an alien spacecraft: Hey, if it worked for the Vulcans in Star Trek, why not us?

10 ) Invite ET to log on: A group of scientists have set up a web site asking for an extra-terrestrial intelligence to send them an e-mail. So far all the responses have been hoaxes, but asking for a shout-out never really hurts.