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Call it the revenge of kooks. Many ufologists have long argued for the existence of a tenth planet beyond the orbit of Neptune. Calling it Nibiru, they said the planet harbored an advanced civilization whose cosmonauts visited the Sumerians on Earth some 4,500 years ago. The defended their claim, saying that we haven't yet spotted Nibiru becasue it had an eliptical, comet-like orbit banked steeply to the plane of the solar sytem.

Find a good hole to hide.

Today's New York Times reports on a newly discovered piece of rock in the far-out solar system that's possibly larger than Pluto. The new body orbits at a puzzling 44-degree angle to the rest of the solar system. Already, astronomers are wondering about the forces that have have kicked it so high up. Is the new body the solar system's tenth planet? Some scientists already started calling Xena. Or will the discovery make Pluto lose its rank as a planet and become a mere cosmic rock? We'll need to wait for answers.

From the Times:

"Astronomers announced yesterday that they had found a lump of rock and ice that was larger than Pluto and the farthest known object in the solar system. The discovery will probably rekindle debate over the definition of "planet" and whether Pluto still merits the designation.
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The new object - as yet unnamed, but temporarily known as 2003 UB313 - is now 9 billion miles away from the Sun, or 97 times as far away as Earth and about three times Pluto's current distance from the Sun. Its 560-year elliptical orbit brings it as close as 3.3 billion miles. Pluto's orbit ranges from 2.7 billion miles to 4.6 billion.

The astronomers do not have an exact size for the new planet, but its brightness and distance tell them that it is larger than Pluto, the smallest of the nine known planets.

"It is guaranteed bigger than Pluto," said Michael E. Brown, a professor of planetary astronomy at the California Institute of Technology and a member of the team that made the discovery. "Even if it were 100 percent reflective, it would be larger than Pluto. It can't be more than 100 percent reflective.""

Image: Orbit of the mythical Nibiru comes via greatdreams.com

The Universe may be big and empty but it's certainly not silent. The cosmos is roaring with all kind of ruckus. Quasars emit massive beams of radio waves, and so do centers of galaxies, massive neutron stars and other exotic cosmic inhabitants.
But you don't need to be big and heavy to grind out radio signals. The solar system puts on a radio show, too, and astronomers have long been tuning in.
Scientists from the University of Iowa, using NASA's Cassini spacecraft, have now recorded two particularly cool and creepy samples from Radio Saturn. (Listen in here and here.)
The scientists said that the radio signals, which they called "Halloween sound track," are related to Saturn's auroras, or northern and southern lights.
The scientists also said that time on this recordings has been compressed and their frequencies down-shifted since the broadcasts were high above the audible frequency range.
The research was published in the current issue of the Geophysical Research Letters.
(For comparison, here's a recorded signal of Radio Jupiter.)

Image: The image corresponds with the first sample from Saturn. "It appears as though the three rising tones are launched from the more slowly varying narrowband emission near the bottom of this display," the scientists said. "If this is the case, it represents a very complicated interaction between waves in Saturn's radio source region, but one which has also been observed at Earth." Credit: NASA/JPL/University of Iowa

Caltech planetary scientist Maciej Konacki has discovered the first planet that never sleeps. The Jupiter-sized planet in the constellation Cygnus belongs to a complex solar system dominated by three different suns. And while multiple stars have been known to circle around each other, astronomers have never seen a planet in such company.
The discovery raises serious questions about what we know about planet formation, a topic frequently discussed on this blog (see previous post.)
Here's why: Latest planet formation theories propose that planets coalesce from a wide protoplanetary dust disks, circling stars much like Saturn's rings. Newborn planets are then pulled inwards towards the parent star. Some are gobbled up by it, some are flung into space like a rock from a sling by the star's gravity, and some settle in stable orbits.
However, theory says, if the parent star is part of a multi-stellar system, the dusk disk formation gets disrupted by the competing gravitational pulls of the different stars, the disk grows too narrow, and planet formation breaks down.
"How that planet formed in such a complicated setting is very puzzling," Konacki said about his discovery. "If we believe that the same basic processes lead to the formation of planets around single stars and components of multiple stellar systems, then such processes should be equally feasible, regardless of the presence of stellar companions. Planets from complicated stellar systems will put our theories of planet formation to a strict test."
The system is about 149 light-years from Earth. The stars are about as close to one another as the distance between the Sun and Saturn.
"In other words, a viewer there would see three bright suns in the sky," Caltech said in a press release. "In fact, the sun that the planet orbits would be a very large object in the sky indeed, given that the planet's "year" is only three and a half days long. And it would be yellow, because the main star of HD 188753 is very similar to our own sun. The larger of the other two suns would be orange, and the smaller red."
Said Konacki: "The environment in which this planet exists is quite spectacular. With three suns, the sky view must be out of this world-literally and figuratively."

Image: This artist's animation shows the view from a hypothetical moon in orbit around the first known planet to reside in a tight-knit triple-star system. Credit: Nasa

In science, as in life, things aren't always what they seem. Take planetary formation.

Back in April 1984, American planetary scientists Bradford Smith and Richard Terrile observed a nearby star called Beta Pictoris and made a startling discovery: for the first time they saw a huge disk of orbiting dust spreading from the star like the swirling skirt of a Russian peasant bride. "I was very, very excited," Terrile told astronomer Ken Croswell, who tells the story in his book Planet Quest. "You look at the fundamental questions of astronomy - the origin of the universe, the origin of life: those are the things that we really, deep down in our souls, want to know, the things that keeps us up at night. Here's a direct link to that," said Terrile.
"Everybody had this feeling that we understood how planets formed, from a flattened disk of material," he told Croswell. "But there was no real hard physical evidence - no picture that you can see. And suddenly, in this blazing, obvious thing, is this picture which is an absolutely classic example of exactly what we thought happened when stars and planets formed. It was a slap in the face that said: Wake up, don't you see what's going on all around you."

Now it looks like we'll need to take another one on the jaw before we figure out how planets form. For Terrile's giddy conjecture about their formation may have been a tad too optimistic. New evidence shows that some disks may just be barren pancakes of dust that will never give birth to any new world.

Scientists from the Harvard-Smithsonian Center for Astrophysics have just discovered a dust disk that is 25 million years old and shows no signs of planet formation. The finding contradicts accepted theory, which says that most protoplanetray disks last only a few million years and rarely longer than 10 million years. "Finding this disk is as unexpected as locating a 200-year-old person," the Center's Lee Hartmann said in a press release. "We don't know why this disk has lasted so long, because we don't know what makes the planetary process start," said his colleague Nuria Calvet.

The disk, which is almost 600 million miles wide, orbits two red dwarf stars located some 350 light years away in the constellation Taurus.

"The disk looks a lot different than most other disks we've seen. This disk looks a lot more evolved than those around younger stars," said Hartmann. "Most stars, by the age of 10 million years, have done whatever they're going to do. If it hasn't made planets by now, it probably never will."

While Hartmann remains pessimistic about the disks chances every bearing a planet, Calvet still gives it a fighting chance. "This disk still has a lot of gas in it, so it may still form giant planets," he said.

Hartmann and Calvet said they want to search for more old disks and find out why some disks survive so much longer than most others.

Said Calvet: "It's important to find more objects like this because they give us clues about the conditions that influence the formation of planets."


Hartmann and Calvet's research will be published in The Astrophysical Journal Letters

Scientists studying massive explosions flaring from a neutron star some 50,000 light years away say the blasts could serve as a powerful new tool for probing the guts of these enigmatic cosmic beasts.
Neutron stars are the last rung on the ladder leading a collapsing star to a black hole. Astrophysicist Fred Zwicky, who have coined the name neutron star, was the first to calculate in the 1930s that gigantic internal pressures in such stars push electrons inside atomic nuclei where protons gobble them up to form neutrons. The density is so huge, some million billion grams per cubic centimeter, that it squeezes the failing star into a sphere with a diameter of just 12 miles. Yet despite further work by Oppenheimer, Wheeler and many others, seven decades after Zwicky's discovery neutron stars hold on to a lot of their mystery, with scientists trying to decipher the details their internal structure.
Now they may get some help from a powerful X-blasts emanating from the neutron star SGR 1806-20, which were recorded last December. Scientists from the University of California San Diego, Italy's National Institute of Astrophysics, Israel and the Netherlands have tried to use the explosions, which in just a fraction a second released more energy than the sun emits in 150,000 years, to learn about what neutron stars look like inside.
"This explosion was akin to hitting the neutron star with a gigantic hammer, causing it to ring like a bell," said Richard Rothschild, an astrophysicist at the University of California's Center for Astrophysics and Space Sciences and one of the authors of the journal report. "Now the question is, What does the frequency of the neutron star's oscillations - the tone produced by the ringing bell - mean?," he asked in a press release.
"Does it mean neutron stars are just a bunch of neutrons packed together? Or do neutron stars have exotic particles, like quarks, at their centers as many scientists believe? And how does the crust of a neutron star float on top of its superfluid core? This is a rare opportunity for astrophysicists to study the interior of a neutron star, because we finally have some data theoreticians can chew on. Hopefully, they'll be able to tell us what this all means."
Where did the hammer come from? The astrophysicists suspect, the release said, that "the burst of gamma-ray and X-ray radiation from this unusually large explosion could have come from a highly twisted magnetic field surrounding the neutron star that suddenly snapped, creating a titanic quake on the neutron star.
"The scenario was probably analogous to a twisted rubber band that finally broke and in the process released a tremendous amount of energy," said Rothschild. "With this energy release, the magnetic field surrounding the magnetar was presumably able to relax to a more stable configuration."
The research for published in the current issue of the Astrophysical Journal.

Image: Artist's conception of the December 27, 2004 gamma ray flare expanding from SGR 1806-20. Credit: NASA

Descartes is dead, long live Spinoza. Neuroscientists and philosophers have now firmly rejected Descartes's mind-body dualism, embracing instead his peer and rival Spinoza, who believed that the soul and the body are one. Using technologies like functional magnetic resonance imaging, or fMRI, they have been probing the brain, seeking neural firing patterns that correspond with awareness and the self. Problem is, fMRI is still fairly crude, making their research quite fuzzy.
But now a team of American and Japanese scientists have proposed a revolutionary method to explore the brain, threading the thinking organ with platinum nanowires 100 times thinner than a human hair. The wires, which would enter the brain through blood vessels like a catheter, "may one day allow doctors to monitor individual brain cells," the researchers said.
That's great news, since one day the method could let them see in clear detail what really happens in the brain and which neurons snap into action when we reflect on our lives and ourselves, when we think of our loved ones, or when we just crave a cup of strong coffee in the morning.
"In this case, we see the first-ever application of nanotechnology to understanding the brain at the neuron-to-neuron interaction level with a non-intrusive, biocompatible and biodegradable nano-probe," said Michael Roco, senior advisor for nanotechnology at the National Science Foundation, which funded the research
The researchers envision "an entire array of nanowires being connected to a catheter tube, which could then be guided through the circulatory system to the brain. Once there, the nanowires would spread into a kind of bouquet, branching out into tinier and tinier blood vessels until they reached specific locations. Each nanowire would then be used to record the electrical activity of a single nerve cells, or small groups of nerve cells."
They also said that the technique could "greatly improve doctors' ability to pinpoint damage from injury and stroke, localize the cause of seizures, and detect the presence of tumors and other brain abnormalities." Since the wires could deliver electrical impulses as well as receive them, the method has potential as a treatment for Parkinson's and similar diseases.
As for finding the neural expression of the soul, the researchers stayed mum. But say it works, it seems that the technique could provide much sought after answers about who we are and where the self and awareness come from.
The research was carried out by scientists from New York University, MIT, and the Univesity of Tokyo. It was published in the current issue of the Journal of Nanoparticle Research.

Photo credit: Rat neurons, Omegafilters

Looking for ways to celebrate the 125 years since Thomas Edison first published his
Science on July 3, 1880, the magazine's editors have decided to hail the demise of ignorance. Tracing the largest holes in our scientific knowledge, the editors published a list of 25 "big questions," which they think have the greatest chance of being answered over the next quarter of century.
Though boredom is a state rarely experienced by Astralavista readers, if you find your brain underutilized over the upcoming long weekend, try to tackle this sampling. Even better, come up with your own and post it here. Here we go:
* What is the universe made of? In the last few decades, cosmologists have discovered that the ordinary matter that makes up stars and galaxies is less than 5 percent of everything there is. What is the nature of the "dark" matter that makes up the rest?
* What is the biological basis of consciousness? In contrast to Rene Descartes' 17th-century declaration that the mind and body are entirely separate, a new view is that whatever happens in the mind arises from a process in the brain. But scientists are only just beginning to unravel those processes.
* Why do humans have so few genes? To biologists' great surprise, once the human genome was sequenced in the late 1990s, it became clear that we only have about 25,000 genes -- about the same numbers as the flowering plant Arabidopsis. The details of how those genes are regulated and expressed is a central question in biology.
* How much can human life span be extended? Studies of long-lived mice, worms and yeast have convinced some scientists that human aging can be slowed, perhaps allowing many of us to live beyond 100, but others think our life spans are more fixed.
* Will Malthus continue to be wrong? In 1798, Thomas Malthus argued that human population growth will inevitably be checked, for example by famine, war or disease. Two centuries later, the world's population has risen sixfold, without the large-scale collapses that Malthus had predicted. Can we continue to avoid catastrophe by shifting to more sustainable patterns of consumption and development?


Image: Artist's impression of the early universe, less than 1 billion years old. Courtesy of A. Schaller of the STScI