We’ve seen the light: Nasa spots light being emitted from “super-Earth” planet

 Super-Earth” Planet

Light glowing from a "super-Earth" planet beyond our solar system has been detected by Nasa’s Spitzer Telescope.

Until now, scientists have never been able to detect infrared light emanating from 55 Cancri E, a super-hot extrasolar planet twice the size and eight times the mass of our own.

Experts are hailing the latest discovery as a historic step towards the eventual search for signs of life on other planets.

55 Cancri E is one of five exoplanets orbiting a bright star named 55 Cancri in a solar system lying in the constellation of Cancer (The Crab).

Previously, Spitzer and other telescopes were able to study the planet by observing how the light from 55 Cancri changed as the planet passed in front of the star.

In the new study, Spitzer instead measured how much infrared light came from the planet itself – revealing some of the planet’s major features.

At 41-light years from Earth, the giant planet is considered uninhabitable.

The giant planet is tidally locked, so one side always faces the star. The telescope found that the sun-facing side is extremely hot, indicating the planet probably does not have a substantial atmosphere to carry the sun's heat to the unlit side.

On its sun-facing side, the surface has a temperature of 1,727 Celsius – or 3,140 degrees Fahrenheit –  That’s hot enough to melt silver or aluminium.

It is calculated that one year on the alien planet lasts just 18 hours.

The new findings are consistent with a previous theory that 55 Cancri E is a water world: A rocky core surrounded by a layer of water in a "supercritical" state where it is both liquid and gas, and topped by a blanket of steam.

Bill Danchi, Spitzer programme scientist at NASA, said: “Spitzer has amazed us yet again. The spacecraft is pioneering the study of atmospheres of distant planets and paving the way for NASA's upcoming James Webb Space Telescope to apply a similar technique on potentially habitable planets.”

Michael Werner, who also works on the Spitzer project, added: “When we conceived of Spitzer more than 40 years ago, exoplanets hadn't even been discovered. Because Spitzer was built very well, it's been able to adapt to this new field and make historic advances such as this.”

The planet was first discovered in 2004 and the new findings are published in the current issue of Astrophysical Journal Letters.

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Comet defies death, brushes up to sun and lives

Comet to Sun

WASHINGTON (AP) — A small comet survived what astronomers figured would be a sure death when it danced uncomfortably close to the broiling sun.

Comet Lovejoy, which was only discovered a couple of weeks ago, was supposed to melt Thursday night when it came close to where temperatures hit several million degrees. Astronomers had tracked 2,000 other sun-grazing comets make the same suicidal trip. None had ever survived.

But astronomers watching live with NASA telescopes first saw the sun's corona wiggle as Lovejoy went close to the sun. They were then shocked when a bright spot emerged on the sun's other side. Lovejoy lived.

"I was delighted when I saw it go into the sun and I was astounded when I saw something re-emerge," said U.S. Navy solar researcher Karl Battams.

Lovejoy didn't exactly come out of its hellish adventure unscathed. Only 10 percent of the comet — which was probably millions of tons — survived the encounter, said W. Dean Pesnell, project scientist for NASA's Solar Dynamics Observatory, which tracked Lovejoy's death-defying plunge.

And the comet lost something pretty important: its tail.

"It looks like the tail broke off and is stuck" in the sun's magnetic field, Pesnell said.

Comets circle the sun and sometimes get too close. Lovejoy came within 75,000 miles of the sun's surface, Battams said. For a small object often described as a dirty snowball comprised of ice and dust, that brush with the sun should have been fatal.

Astronomers say it probably didn't melt completely because the comet was larger than they thought.

The frozen comet was evaporating as it made the trip toward the sun, "just like you're sweating on a hot day," Pesnell said.

"It's like an ice cube going by a barbecue grill," he said.

Pesnell said the comet, although only discovered at the end of November by an Australian observer, probably is related to a comet that came by Earth on the way to the sun in 1106.

As Comet Lovejoy makes its big circle through the solar system, it will be another 800 or 900 years before it nears the sun again, astronomers say.

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