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Close approaches by Near Earth Asteroids...

Started by Whitters, Sep 24, 2004, 16:01:00

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Rick

Surprising Recent Discoveries of Three Large Near-Earth Objects

Two surprisingly large Near-Earth Asteroids have been discovered in just the last week or so, as well as a third moderately large asteroid which surprisingly has also gone undetected until now, even though it can pass close enough to the Earth to be classified as "potentially hazardous". Not since 1983 has any near-Earth asteroid been found as large as the approximately 20-kilometer (12-mile) size of the two new large ones. In fact, there are only three other known near-Earth asteroids that are of comparable size or larger than the two new large ones.

It is important to note that none of these three new large near-Earth asteroids can come close enough to the Earth to represent a near-term threat to our planet.

More: http://neo.jpl.nasa.gov/news/news181.html

Rick

The previous story's been updated thus:

Near-Earth Object 2013 US10 Turns Out to Be a Long-Period Comet

While initial reports from the Minor Planet Center in Cambridge MA categorized object 2013 US10 as a very large near-Earth asteroid, new observations now indicate that it is, in fact, a long period comet, and it is now designated C/2013 US10 (Catalina). The comet was discovered by the Catalina Sky Survey near Tucson AZ on October 31, 2013 and linked to earlier pre-discovery Catalina observations made on September 12. The initial orbit suggested this object is a large, short period, near-Earth asteroid, as reported here yesterday. An updated orbit, issued today by the Minor Planet Center removed the September 12th observations that belong to another object and include earlier pre-discovery August and September observations made by the Catalina Sky Survey, the ISON-HD observatory in Russia and Hawaii's Pan-STARRS group. The new orbit indicates that this object is in a long-period, near parabolic orbit about the sun. Furthermore, observations made last night at the Canada-France-Hawaii telescope indicate the object is showing modest cometary activity, which means that yesterday's rough estimate for the object's size (about 20 kilometers or 12 miles) must now be completely revised. A new size estimate is not yet available, but it could very well be much smaller than yesterday's estimate.

Rick

Radar Images of near-Earth Asteroid 2006 DP14

A collage of radar images of near-Earth asteroid 2006 DP14 was generated by NASA scientists using the 230-foot (70-meter) Deep Space Network antenna at Goldstone, Calif., on the night of Feb. 11, 2014.

Delay-Doppler radar imaging revealed that the asteroid is about 1,300 feet (400 meters) long, 660 feet (200 meters) wide, and shaped somewhat like a big peanut. The asteroid's period of rotation is about six hours. The asteroid is of a type known as a "contact binary" because it has two large lobes on either end that appear to be in contact. Previous radar data from Goldstone and the Arecibo Observatory in Puerto Rico has shown that at least 10 percent of near-Earth asteroids larger than about 650 feet (200 meters) have contact binary shapes like that of 2006 DP14. The data were obtained over an interval of 2.5 hours as the asteroid completed about half a revolution. The resolution is about 60 feet (19 meters) per pixel.

More: http://www.jpl.nasa.gov/news/news.php?release=2014-060

Les R

#18
Asteroid To Fly Between Earth And Moon 9pm GMT 5-2-14




Scientists say a 30m-wide (100ft) asteroid will pass between the moon and Earth later, providing spectacular views for anyone with a good telescope.

The space rock called 2014 DX110 is the length of three double-decker buses and will come within 214,745 miles (346,599km) of the planet at around 9pm UK time.

It will be moving at 33,000mph (53,108kph).

Nasa's Jet Propulsion Laboratory has been monitoring its flight and classifies it as one of a number of Apollo-class asteroids, which cross the Earth's orbit.

The Chelyabinsk asteroid which exploded over the Russian region last year was also Apollo-class.



Professor Tim O'Brien, from the University of Manchester's Jodrell Bank Observatory, said: "There is an incredibly tiny chance of 2014 DX110 getting closer to Earth but everything indicates that it's nothing to worry about.

"This asteroid was only spotted last month and we now know there are many more like it that are, as yet, undetected.

"The Chelyabinsk meteor event was a reminder of the damage these things can do so it's important to keep monitoring and looking for them.

"On a comforting note though, it's good to remember that there are many more smaller, and harmless objects, than large ones out there."

Scientists say the rock will be too faint to see with the naked eye but should be visible with a reasonably sized telescope.

Astronomers will also need to work out exactly where it will cross the night sky, so more experienced stargazers might have a better chance of spotting it.

The Virtual Telescope Project and Slooh will be sharing real-time images in a live, online event.

:: Watch Sky News live on television, on Sky channel 501, Virgin Media channel 602, Freeview channel 82 and Freesat channel 202.







MarkS

Quotespectacular views for anyone with a good telescope.

Hmmm ...

30m at a distance of 350,000km subtends an angle of 0.02 arcsec.
You won't see much detail.

Mark

Mac

Quotespectacular views for anyone with a good telescope.

What a dot?

hmmmmmm,
this sounds exactly like the post war we had with a certain individual who claimed to be able to photograph,
huge amounts of detail on pluto from earth.

He posted on one of the dpreview forums, claiming to show amazing details of charon and pluto.
Taken from earth with a 14" lx200 with a SINGLE 60s CCD image with no other processing.

http://www.spacenow.com.br/pluto1.html

Well, it was explained to him that the resolution, size and distance means everything he said was pie in the sky.
And all he was processing was optical artifacts.
He was given ample chances to prove his statements with images that were taken locally, but declined.

http://www.spacenow.com.br/

have a laugh.
Heres the dp posting.

http://www.dpreview.com/forums/post/52922880

Mac.

MarkS

It's expected to be a mag 15 object.

Quotespectacular views for anyone with a good telescope.

I guess some folk get really excited by mag 15 dots  :)

Rick

Quote from: Les R on Mar 05, 2014, 14:02:45Watch Sky News live on television, on Sky channel 501, Virgin Media channel 602, Freeview channel 82 and Freesat channel 202.

Hmmm...

Quote from: MarkS on Mar 05, 2014, 16:51:13I guess some folk get really excited by mag 15 dots  :)

Standard media hyper-hype, I figure...

MarkS

Quote from: Mac
this sounds exactly like the post war we had with a certain individual who claimed to be able to photograph,
huge amounts of detail on pluto from earth.

Thanks for posting that - I really needed a good laugh!!

mickw

Growing Old is mandatory - Growing Up is optional

MarkH

Maybe they ought to be more worried about apophos 2029  :bang:

Rick

Asteroid Will Safely Pass Closer Than Moon Wednesday

As happens about 20 times a year with current detection capabilities, a known asteroid will safely pass Earth Wednesday closer than the distance from Earth to the moon.

This asteroid, 2014 DX110, is estimated to be about 100 feet (30 meters) across. Its closest approach to Earth will be at about 217,000 miles (about 350,000 kilometers) from Earth at about 1 p.m. PST (4 p.m. EST) on March 5. The average distance between Earth and its moon is about 239,000 miles (385,000 kilometers).

More: http://www.jpl.nasa.gov/news/news.php?release=2014-068

MarkS

So - did anyone watch this "spectacular view" live on Sky News?

Mac

No but i did manage to photograph it over a period of time.
Haven had time to add the flats, darks or bias yet.

Here's a set of four.





                           .

                         .

                       .

                     .



Mac.


nearly as good as the old M1 photo.  ;)

mickw

Growing Old is mandatory - Growing Up is optional