BBC.CNN WORLD NEWS
Showing posts with label astronomers. Show all posts
Showing posts with label astronomers. Show all posts

Wednesday, June 20, 2012

Huge Asteroid to Fly by Earth Today: How to Watch Online

Huge Asteroid to Fly by Earth Today

An asteroid the size of a city block is set to fly by Earth June 14, and you may be able to watch it happen live.

The near-Earth asteroid 2012 LZ1, which astronomers think is about 1,650 feet wide, will come within 14 lunar distances of Earth Thursday evening. While there’s no danger of an impact on this pass, the huge space rock may come close enough to be caught on camera.

That’s what the team running the Slooh Space Camera thinks, anyway. The online skywatching service will train a telescope on the Canary Islands on 2012 LZ1 and stream the footage live, beginning at 8:00 p.m. EDT Thursday.

You can watch the asteroid flyby on Slooh’s website.

2012 LZ1 just popped onto astronomers’ radar this week. It was discovered on the night of June 10-11 by Rob McNaught and his colleagues, who were peering through the Uppsala Schmidt telescope at Siding Spring Observatory in Australia.

Researchers estimate that the space rock is between 1,000 and 2,300 feet wide. On Thursday evening, it will come within about 3.35 million miles of our planet, or roughly 14 times the distance between Earth and the moon.

Because of its size and proximity to Earth, 2012 LZ1 qualifies as a potentially hazardous asteroid. Near-Earth asteroids generally have to be at least 500 feet wide and come within 4.65 million miles of our planet to be classified as potentially hazardous.

2012 LZ1 is roughly the same size as asteroid 2005 YU55, which made a much-anticipated flyby of Earth last November. But 2005 YU55 gave our planet a much closer shave, coming within 202,000 miles (325,000 km) of us on the evening of Nov. 8. A space rock as big as 2005 YU55 hadn’t come so close to Earth since 1976, researchers said.

Astronomers have identified nearly 9,000 near-Earth asteroids, but they think many more are out there, waiting to be discovered.

News by Mashable

Read current news at http://bbc-cnn-worldnews.blogspot.com


Saturday, December 17, 2011

Comet defies death, brushes up to sun and lives

comet
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.

News by Yahoo


Read current news at http://bbc-cnn-worldnews.blogspot.com