One year of Moon cycle within 2.5 minutes

many of you peoples must know that moon is tidally locked to the earth means its one side always faces to the earth and another on the dark side (remember transformers: dark of the moon?) its takes approximately 27 days to revolve around earth and its own axis. have a look in this amazing video.

http://www.youtube.com/watch?v=F9pVaTQinIw

An astroid to come closer to earth than Moon

Never mind the recent spate of satellite showers. An asteroid the size of an aircraft carrier is sailing toward Earth, NASA says.

Never fear, however. The space agency says that although next week's flyby of Asteroid 2005 YU55 will bring the rock closer to our home planet than even the moon gets, the asteroid will cruise safely past, leaving in its wake not destruction but data.

The agency has already begun using radio waves to scan the 1,300-foot-wide space rock, which will get closest to Earth on Tuesday at about 3:30 p.m. PT. With antennas at its Deep Space Network at Goldstone, Calif., and the Arecibo Planetary Radar Facility in Puerto Rico, NASA hopes to gather a wealth of detail about the asteroid's surface features, shape, dimensions, and other physical properties.

An extraterrestrial rock hasn't come this close to Earth since 1976, and we won't witness another such close encounter till 2028, NASA says. YU55 itself hasn't come this near for 200 years. Amateur astronomers who want to check it out for themselves will need a telescope with an aperture of 6 inches or larger, the agency says.

Radar observations made of YU55 in 2010 reveal it to be approximately spherical and slowly spinning, with a rotation period of about 18 hours.

Lightest Planet Till Date

A distant world known as Gliese 581e (foreground in this artist's conception) is the lightest planet outside our solar system found to date, astronomers announced in April 2009. The planet, one of four orbiting a red dwarf star, is just less than twice the mass of Earth.

Astronomers also announced that one of the system's other planets, Gliese 581d, is an Earthlike world that orbits in the right zone to host liquid water, and thus potentially life.

Smallest planet outside our solar system (YET..)

 

The smallest planet yet spied outside our solar system has been found orbiting a sunlike star about 560 light-years away, astronomers announced today. Known as Kepler-10b, the planet is just 1.4 times Earth's size and 4.6 times its mass.
The planet, found using NASA's Kepler spacecraft, is the first of the more than 500 known exoplanets that's definitively rocky—much like Earth, Mars, Venus, or Mercury—the study team says. Launched in March 2009, Kepler was designed to hunt for potentially habitable Earthlike planets.
Astronomers have been studying Kepler-10b (name of the planet) since its discovery in 2009, when the team detected a periodic dimming of the host star as the planet passed in front of the star.
Finding such a small planet this way was no easy feat—seen from a similar distance, Earth passing in front of the sun would cause a 0.01 percent reduction in the star's brightness, said Natalie Batalha of San Jose State University, lead author of an upcoming paper describing the find.
"Imagine you have 10,000 light bulbs and you take one away. That's the change in brightness we're looking for," Batalha said today during a meeting of the American Astronomical Society in Seattle, Washington.
Still, after using Kepler and other instruments to precisely calculate the new planet's size, mass, and density, Batalha said, "we know without question that this is a rocky world."

New planet: the sibling of earth?

A new planet found about 36 light-years away could be one of the most Earthlike worlds yet—if it has enough clouds, a new study says.

The unpoetically named HD85512b was discovered orbiting an orange dwarf star in the constellation Vela. Astronomers found the planet using the European Southern Observatory's High Accuracy Radial velocity Planet Searcher, or HARPS, instrument in Chile.

Radial velocity is a planet-hunting technique that looks for wobbles in a star's light, which can indicate the gravitational tugs of orbiting worlds.

The HARPS data show that the planet is 3.6 times the mass of Earth, and the new world orbits its parent star at just the right distance for water to be liquid on the planet's surface—a trait scientists believe is crucial for life as we know it.

"The distance is exactly the limit where you want to be to have liquid water," said study leader Lisa Kaltenegger of the Harvard-Smithsonian Center for Astrophysics and the Max Planck Institute for Astronomy.

"If you scale it to our system, it's a bit further out than Venus is to our sun." At that distance, the planet likely receives a bit more solar energy from its star than Earth does from the sun. (Explore an interactive solar system.)

But Kaltenegger and colleagues calculate that a cloud cover of at least 50 percent would reflect enough of the energy back into space to prevent overheating.

On average, Earth has 60 percent cloud cover, so partly cloudy skies on HD85512b are "not out of the question," she said.

Of course, clouds of water vapor depend on the presence of an atmosphere similar to Earth's, something that can't be detected on such distant planets with current instruments.

Models of planet formation predict that planets with more than ten times Earth's mass should have atmospheres dominated by hydrogen and helium, Kaltenegger said. Less massive worlds—including HD85512b—are more likely to have Earthlike atmospheres, made mostly of nitrogen and oxygen.

New World "A Strong Candidate" for Habitability

So far, the newly detected planet is only the second rocky world outside our solar system to be confirmed in its star's habitable zone—the region around a star that's not too hot and not too cold for liquid water.

The other contender, planet Gliese 581d, was previously discovered using the HARPS instrument. This world lies just on the cool edge of its star's habitable zone. 

Another promising planet, Gliese 581g, was discovered in 2010 and dubbed the most Earthlike planet yet. But controversy surrounds the claim, with some experts declaring that the entire planet is actually a data glitch.

Manfred Cuntz, director of the astronomy program at the University of Texas, Arlington, noted that more information is needed before anyone can speculate whether aliens are wandering around the newfound planet.

"It's not their fault no extra information [about the planet's atmosphere] is available right now," Cuntz said of the research team. "It looks like this is a strong candidate, in principle."

In addition to size and location, HD85512b has two other points in its favor for potentially harboring life, Cuntz said.

The planet's orbit is nearly circular, which would provide a stable climate, and its parent star, HD85512, is older—and therefore less active—than our sun, which would lower the likelihood of electromagnetic storms damaging the planet's atmosphere.

Not only that, but in principle, the age of the system—5.6 billion years—"gives life a chance to originate and develop," he said. By contrast, our own solar system is thought to be about 4.6 billion years old.

New Planet a Great Place for Yoga?

Given current limits on space travel, it's unlikely for now that humans will get to visit HD85512b.

But if we could get there, the newfound planet might seem like a fairly alien world: muggy, hot, and with a gravity 1.4 times that of Earth's, study leader Kaltenegger said.

On the bright side, "hot yoga might be one of the things you don't have to pay for there," she quipped.

The paper describing HD85512b appears online at arXiv.org and has been accepted for publication in the journal Astronomy and Astrophysics.