Asteroid Earth crossing at only 12000 kms from us

[ricci]

A little asteroid, with diameter of only 13 meter, will pass on June 27 (13:26 TDT) at 0.000123 A.U. from the Earth, 12000 kilometers from us.

www.pierpaoloricci.it/news_eng.htm

[ngcles]

Hi Ricci & All,

Further article on this story here:

http://www.skyandtelescope.com/obser...124430479.html

Australia and New Zealand are well placed to observe.


Best,

Les D

[Greg Bryant]

Here's a very nice animation of the passage of the asteroid. Makes you realise just how close it's going to get, and how its path will be affected by Earth's gravity.

http://orbit.psi.edu/~tricaric/2011MD.html

(I say "asteroid" but there's a minute chance that it may be man-made space junk. We'll know more soon.)

Greg

[Steffen]

Originally Posted by ngcles

Australia and New Zealand are well placed to observe.

Is this observable? I mean, a dim, fast moving 10m object…?

Cheers
Steffen.

[Rob_K]

Originally Posted by Steffen

Is this observable? I mean, a dim, fast moving 10m object…?

Cheers
Steffen.

Technically yes, but a big, big challenge for the reasons you outlined Steffen! The original ephemeris was based on a very short arc but should be refined over the next few days. Might be academic anyway unless the weather improves!

Cheers -

[ngcles]

Hi All,

Originally Posted by Rob_K

Technically yes, but a big, big challenge for the reasons you outlined Steffen! The original ephemeris was based on a very short arc but should be refined over the next few days. Might be academic anyway unless the weather improves!

Cheers -

Yes very much observable but will be hard to find. You will definitely need a Topocentric ephemeris. Geocentric is of no use because your location on Earth will greatly affect where it is seen in the sky (due to parallax). There is provision at the NASA/JPL site to generate a topographic ephemeris but I just can't find it at present and have to head out.

Generate a topo ephemeris with just an hour or so to go before you observe. The orbital elements will undoubtedly change as the next few days pass by. Because this pass is so close, small change in elements can produce substantial changes to an ephemeris.

At best in Australia it will be in the 11/12th magnitude range -- well within range of moderate-sized 'scopes.


Best,

Les D

[Rob_K]

Originally Posted by ngcles

Hi All,



Yes very much observable but will be hard to find. You will definitely need a Topocentric ephemeris. Geocentric is of no use because your location on Earth will greatly affect where it is seen in the sky (due to parallax). There is provision at the NASA/JPL site to generate a topographic ephemeris but I just can't find it at present and have to head out.

The JPL Small Body Database browser seems to be working OK and will generate an ephemeris for a particular location - put 2011 MD in the search box, hit enter, and on the resultant page click on the "ephemeris" link. Then just change Observer Location parameters to your own (Lat/long, height).
http://ssd.jpl.nasa.gov/sbdb.cgi

Cheers -

[Steffen]

Excellent, hopefully someone will get a chance to image it.

Good old XEphem would calculate topocentric ephemerides if you fed it orbital elements. It used to be the premier ephemeris tool, I wonder what happened to it when everybody turned to "photorealism" in astronomy apps...

Cheers
Steffen.

[Mliss (Mel)]

Originally Posted by ngcles

Hi Ricci & All,

Further article on this story here:

http://www.skyandtelescope.com/obser...124430479.html

Australia and New Zealand are well placed to observe.


Best,

Les D

That's a great article Les!

Just hoping we're cloud free

[astroron (Ron)]

Please correct me if I am wrong , but from what I understand it is closest to earth at about 22.00 UT which is 08.00 in the morning here so will not be visible
Cheers

[astroron (Ron)]

I am wondering if there are two different objects discussed in this thread ?
Seems so.