Arecibo Observatory finds asteroid 2012 LZ1 to be twice as big as first believed

Jun 21, 2012
Arecibo Observatory finds asteroid 2012 LZ1 to be twice as big as first believed
Asteroid 2012 LZ1 is roughly spherical and rotates once around every 10-15 hours. This detailed image was taken when the asteroid was 10 million kilometers (6 million miles) away. The resolution is 7.5 m (25 feet), equivalent to seeing a basketball in New York City from Puerto Rico.

(Phys.org) -- Using the planetary radar system at Arecibo Observatory, astronomers have determined that asteroid 2012 LZ1 is twice as large as originally estimated based on its brightness, and large enough to have serious global consequences if it were to hit the Earth. However, a new orbit solution also derived from the radar measurements shows that this object does not have any chance of hitting the Earth for at least the next 750 years.

Asteroid 2012 LZ1 was discovered on June 10, 2012, at Siding Spring Observatory in Australia, and was classified as potentially hazardous by the Minor Planet Center because its preliminary orbit brings it close to Earth (within 20 lunar distances). Scientists at Arecibo observed the asteroid on June 19, 2012, to measure its orbit more precisely and to determine its size, rotation rate, and shape, and found it to be about 1 kilometer (0.6 miles) in its largest dimension. The new size determination suggests that 2012 LZ1 must be quite dark, reflecting only 2-4% of the light that hits it.

"The sensitivity of our radar has permitted us to measure this asteroid's properties and determine that it will not impact the Earth at least in the next 750 years," said Dr. Mike Nolan, Director of Planetary Radar Sciences at . Dr. Ellen Howell added: "This object turned out to be quite a bit bigger than we expected, which shows how important can be, because we're still learning a lot about the population of asteroids."

Explore further: Computer model shows moon's core surrounded by liquid and it's caused by Earth's gravity

More information: Scientists who worked on this investigation: Ellen S. Howell (Arecibo Observatory), Michael C. Nolan (Arecibo Observatory), Israel Cabrera (Arecibo Observatory), Jon Giorgini (Jet Propulsion Laboratory), and Marina Brozovic (Jet Propulsion Laboratory).

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User comments : 6

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Vendicar_Decarian
2.7 / 5 (7) Jun 21, 2012
The Dog of the bible will protect us.
Feldagast
3.7 / 5 (3) Jun 22, 2012
Isn't that just trolling?
PS3
1 / 5 (2) Jun 22, 2012
I heard there is only like 7 people that watch the sky in the states and that any coming sun side will can't detect at all unless very big and only maybe 24 hour in advance.
Riks
not rated yet Jun 25, 2012
Uhm, PS3: "I heard" is exemplary hearsay.
Show us your calcs!
GSwift7
1 / 5 (1) Jun 26, 2012
Uhm, PS3: "I heard" is exemplary hearsay.
Show us your calcs!


Here's an official status update from NASA dated Oct 2010. Not too much has changed since this report, as it includes things that were already planned at that time but not yet complete.

http://www.whiteh...ouse.pdf

and that any coming sun side will can't detect at all unless very big and only maybe 24 hour in advance


Not exactly, but kinda. Most NEO's have orbits inside Jupiter, which means that they have a relatively short orbit frequency, like between 1 and 5 years, for example. So, one of those would only be inbound from the direction of the sun once in a while. There should be opportunities to spot them at different times of our year.

The few NEO's with long orbit periods are the bigger problem. Some only swing by once every thousand years or so, and they are moving like a bat out of hell when they get here.
PS3
1 / 5 (2) Jun 26, 2012
Uhm, PS3: "I heard" is exemplary hearsay.
Show us your calcs!


I saw it on Phil Plait's old tv show,he went to the place they do the work.