In a timed exposure, spectators watch from Cocoa Beach as the Kepler satellite launches from Cape Canaveral Air Force Station, Fla. March 6.

NASA’s Kepler spacecraft blasted off from Kennedy Space Center in Florida on Friday on a three-year mission to find Earth’s twin, a Goldilocks planet where it’s neither too hot nor too cold, but just right for life to take hold.

The Delta II rocket, carrying the widest-field telescope ever put in space, lifted off the launch pad at Cape Canaveral at 10:49 p.m. Eastern time.

The $590-million Kepler mission is jointly managed by JPL and NASA’s Ames Research Center in the Bay Area. The spacecraft carries a 15-foot-long telescope with a 55-inch mirror that can scrutinize a wide star field for the telltale dimming of starlight that occurs when a planet crosses in front of it, known as a transit.

Over the last decade, scientists have employed the same technique with ground-based telescopes to discover 340 planets circling other stars. But because the optics of ground-based instruments are compromised by atmospheric interference, most of the planets found so far are Jupiter-like gas giants that orbit so close to their parent stars that any life forms would be incinerated.

The orbiting Hubble Space Telescope, whose optics are not hampered by Earth’s atmosphere, was designed to see deeply but very narrowly.

Kepler’s field of view is 33,000 times wider than Hubble’s, or about the size of a human hand held up to the sky. The Cygnus-Lyra region near the plane of the Milky Way encompasses about 4.5 million stars. But most of those are too big or hot to allow a habitable zone close enough to the star for Kepler to see a transit.

The science team has selected about 150,000 sun-like stars for Kepler to analyze. Over time, Fanson said, the number will be winnowed down to about 100,000 in three classes: G-type stars, which are similar in size and age to the sun; K- and M-type stars, which are slightly smaller and cooler; and A- and F-class stars, which are somewhat bigger.

Earth is in the center of the habitable zone around the sun, but with stars of other classes, that zone would be closer to the star or farther out.

Kepler’s telescope is outfitted with a sophisticated camera that will stare unblinkingly at the star field. The whole area will be imaged every six seconds, then stored in 30-minute chunks.

Once a month, Kepler will do a pirouette in space to download its stored data, Fanson said.

Full Article…

Kepler blasts off in search of Earth-like planets – Los Angeles Times.

The adult human brain is surprisingly malleable: it can rewire itself and even grow new cells. Here are some habits that can fine-tune your mind

IMAGE COMPOSITION BY SCIENTIFIC AMERICAN MIND; JULIE FELTON ISTOCKPHOTO (brain); DEAN TURNER ISTOCKPHOTO (background)

Amputees sometimes experience phantom limb sensations, feeling pain, itching or other impulses coming from limbs that no longer exist. Neuroscientist Vilayanur S. Ramachandran worked with patients who had so-called phantom limbs, including Tom, a man who had lost one of his arms.

Ramachandran discovered that if he stroked Tom’s face, Tom felt like his missing fingers were also being touched. Each part of the body is represented by a different region of the somatosensory cortex, and, as it happens, the region for the hand is adjacent to the region for the face. The neuroscientist deduced that a remarkable change had taken place in Tom’s somatosensory cortex.

Ramachandran concluded that because Tom’s cortex was no longer getting input from his missing hand, the region processing sensation from his face had slowly taken over the hand’s territory. So touching Tom’s face produced sensation in his nonexistent fingers.

This kind of rewiring is an example of neuroplasticity, the adult brain’s ability to change and remold itself. Scientists are finding that the adult brain is far more malleable than they once thought. Our behavior and environment can cause substantial rewiring of the brain or a reorganization of its functions and where they are located. Some believe that even our patterns of thinking alone are enough to reshape the brain.

Researchers now know that neurogenesis (the birth of new neurons) is a normal feature of the adult brain. Studies have shown that one of the most active regions for neurogenesis is the hippocampus, a structure that is vitally important for learning and long-term memory.

Neurogenesis also takes place in the olfactory bulb, which is involved in processing smells. But not all the neurons that are born survive; in fact, most of them die. To survive, the new cells need nutrients and connections with other neurons that are already thriving. Scientists are currently identifying the factors that affect the rate of neurogenesis and the survival of new cells. Mental and physical exercise, for instance, both boost neuron survival.

Full article here…

Six Ways to Boost Brainpower: Scientific American.

NASA’s Swift Gamma-Ray Explorer satellite took this shot of Comet Lulin on Jan. 28, and regular folks may be able to catch their own glimpse with binoculars in a few days.

The image was taken as the comet was passing through the constellation Libra, 100 million miles from Earth and 115 million miles from the sun. It combines data from Swift’s optical and ultraviolet telescope (the blue colors) and its X-ray telescope (red). The star-field background comes from a Digital Sky Survey image.

Lulin’s tail — grit and grains from the comet’s rock-and-ice surface pushed off into space by solar radiation — extends to the right. Lulin is shedding 800 gallons of water every second, according to NASA astronomers. That’s enough to fill an Olympic-size swimming pool in less than 15 minutes.

Solar radiation also breaks comet water down into hydroxyl particles, composed of one oxygen and one hydrogen molecule. Swift determined that the hydroxyl cloud around Lulin is about 250,000 miles wide, slightly greater than the distance from the Earth to the moon.

Lulin, discovered in July 2007, is now visible to the naked eye in dark, rural skies. But the view will get better: On the night of Feb. 23, Lulin will pass within 38 million miles of Earth, appearing about 2 degrees south-southwest of Saturn in the night sky. Stargazers with binoculars should get a good look. By mid-March, Lulin will have zoomed off into deep space and out of sight.

Rare Comet Close-Up Coming to a Sky Near You | Wired Science from Wired.com.

In high doses, ultraviolet light can damage skin and DNA molecules, but the body does need some UV light to help us produce vitamin D. Our bodies use melanin to regulate how much UV light our skin lets in.

Courtesy George Chaplin

Ultraviolet Light And Pregnancy

Because women build babies in their wombs, they need more vitamin D to produce extra calcium for the baby’s bones. Could that explain this difference: When scientists look at the underarm skin of men and women in every color group of humans, the women on average are always lighter than the men. Are the ladies lighter to produce a little extra Vitamin D for the babies?

• Listen: Dr. Nina Jablonski describes the “Under Arm” test.

To begin, please point your elbow to the ceiling.

Then imagine yourself naked.

Then look at the patch of skin on the inside of your upper arm, the part of you that almost never sees the sun.

Whatever color you see there is what experts call your basic skin color, according to professor Nina Jablonski, head of the Penn State Department of Anthropology.

And that color, the one you have now, says Jablonski, is very probably not the color your ancient ancestors had — even if you think your family has been the same color for a long, long time.

Different Place, Different Color

Skin has changed color in human lineages much faster than scientists had previously supposed, even without intermarriage, Jablonski says. Recent developments in comparative genomics allow scientists to sample the DNA in modern humans.

By creating genetic “clocks,” scientists can make fairly careful guesses about when particular groups became the color they are today. And with the help of paleontologists and anthropologists, scientists can go further: They can wind the clock back and see what colors these populations were going back tens of thousands of years, says Jablonski.

She says that for many families on the planet, if we look back only 100 or 200 generations (that’s as few as 2,500 years), “almost all of us were in a different place and we had a different color.”

Over the last 50,000 years, populations have gone from dark pigmented to lighter skin, and people have also gone the other way, from light skin back to darker skin, she says.

“People living now in southern parts of India [and Sri Lanka] are extremely darkly pigmented,” Jablonski says. But their great, great ancestors lived much farther north, and when they migrated south, their pigmentation redarkened.

“There has probably been a redarkening of several groups of humans.”

Why We Change Color

The repigmenting process is increasingly well understood.

“Humans started in Africa,” Jablonski says, the part of Africa near the equator where it is intensely sunny with lots of ultraviolet light.

Ultraviolet light, or UV, in high doses can age the skin and damage the DNA molecule, which makes it harder to build a fetus. Not to mention that ultraviolet light can sometimes cause skin cancer.

On the other hand, if a human is plopped down in, say, Norway, where the days can be short and there is precious little ultraviolet light, this creates problems, too. All vertebrate animals need ultraviolet light to help produce vitamin D. Vitamin D helps us absorb calcium from our food to build strong bones. If we don’t get enough ultraviolet light, we’re less likely to survive to reproductive age to produce strong-boned babies.

Thus the dilemma: People who live in sunny climes around the equator have too much UV. People who move away from the equator eventually have too little UV.

Hooray For Melanin

The solution is what Jablonski calls “a really cool molecule”: melanin. In different concentrations, melanin makes skin lighter or darker. Kind of like a Venetian blind, it can let UV light in or keep it out.

Melanin has evolved in many different animals. Humans have had it for a long, long time and what Jablonski and others have learned is that when early humans migrated from the equator, their melanin levels changed.

That doesn’t mean they lost their tans. It means they had very specific genetic changes that allowed them to live and successfully reproduce in less sunny places. Darwin teaches that these changes began randomly. Somebody in the population at some point had a baby, and that baby, just by chance, had a little change in its DNA that made her skin, for example, a little lighter. When that baby moved north to Europe, lighter skin gave her an advantage as a grown-up, because it helped her produce strong-boned babies who could survive and have babies of their own.

Successive mutations created successive generations of lighter and lighter people as they moved north.

“This, in short, really created the gradation of skin color that we see in modern humans today,” says Jablonski. Her map of UV radiation levels on Earth closely mirrors the array of skin colors on Earth.

Skin Color Is A Fleeting Thing

The big surprise is how fast these changes can occur.

“Our original estimates were that [skin color changes] occurred perhaps at a more stately pace,” Jablonski says. But now they’re finding that a population can be one color (light or dark) and 100 generations later — with no intermarriage — be a very different color.

Figuring 25 years per generation (which is generous, since early humans walked naked through the world — clothes slow down the rate), that’s an astonishingly short interval.

It’s “a blink of an eye,” she says.

Audio & More available at NPR (Click Below)

Your Family May Once Have Been A Different Color : NPR.