2006 Hz51

[Blob]

Hum,
The asteroid, 2006 HZ51, is the biggest object currently on NASA-JPL's list of objects that might strike the Earth.
It has an estimated diameter of 782 meters, and has the nearest-term possible Earth-impact date of anything on the list: just over two years away, on the first day of summer 21 June, 2008.
An object that big would be capable of devastating a continent, and wreaking havoc with the Earth's climate for years.

The odds of impact currently stand at just one in six million, with these odds predicted to diminish with additional observations.
2006 HZ51 was discovered on 27 April 2006, and has an estimated Mass of 6.5¹¹ kg.

Currently, analysis based on 13 observations spanning 1.1145 days, over the period of 2006-Apr-27.16042 to 2006-Apr-28.27491, has given the asteroid a Torino Scale (maximum) of 0.


Ephemeris:
2006 HZ51 a,e,i = 3.72, 0.71, 13 q = 1.0753
Date TT R. A. (2000) Decl. .... Delta . r ... Elong. Phase V
2006 04 25 11 06.44 +33 02.9 0.649 1.420 116.6 39.3 20.0
2006 05 05 11 02.08 +31 02.5 0.622 1.341 108.3 45.6 19.9
2006 05 15 11 03.37 +28 01.3 0.595 1.267 101.1 51.5 19.9
2006 05 25 11 10.12 +24 00.1 0.563 1.202 95.2 57.0 19.8
2006 06 04 11 21.99 +18 53.2 0.528 1.148 90.6 62.1 19.7
2006 06 14 11 38.69 +12 30.2 0.490 1.107 87.4 66.4 19.6
2006 06 24 12 00.28 +04 36.5 0.451 1.083 86.0 69.5 19.5
2006 07 04 12 27.69 -04 59.6 0.418 1.075 86.5 70.7 19.3
2006 07 14 13 02.71 -16 08.2 0.395 1.086 89.3 69.3 19.2
2006 07 24 13 48.17 -27 52.3 0.391 1.114 94.1 65.4 19.1
2006 08 03 14 46.91 -38 21.0 0.410 1.158 99.9 59.7 19.1
2006 08 13 15 57.86 -45 35.9 0.453 1.215 105.4 53.5 19.3
2006 08 23 17 12.50 -48 48.5 0.519 1.282 109.5 48.1 19.5
2006 09 02 18 19.53 -48 42.7 0.606 1.356 111.8 43.7 19.9
2006 09 12 19 13.61 -46 39.5 0.711 1.437 112.4 40.3 20.2
2006 09 22 19 55.83 -43 42.7 0.832 1.522 111.6 37.8 20.6
2006 10 02 20 29.42 -40 27.8 0.968 1.609 109.6 35.9 21.0
2006 10 12 20 57.11 -37 11.9 1.117 1.698 106.6 34.3 21.4
2006 10 22 21 20.83 -34 02.0 1.279 1.788 102.9 32.9 21.8

[antoniseb]

It'll be interesting to see how this resolves. The object has a 2.57 year orbit, and we seem to be near the perihelion end of the orbit.

[mantiss]

Hmm it seems to have vanished from http://neo.jpl.nasa.gov/risk/2006hz51.html

But when you check the orbit on their little java applet it shows the asteroid nowhere near in June 2008. Any ideas?

[antoniseb]

Additional observations made on May 3rd (today) show that this object has a perihelion of 1.1 AU and an aphelion of about 4.6AU, and will never get close to the Earth. It has been removed from all threat databases.

[mantiss]

Ah, good, I was wondering why it did not show even on the close approaches anymore, as I was sure that the risk of impact would have been negligible, but still a big rock like that coming close would have made a good opportunity for a cheap asteroid mission =)

[Kullat Nunu]

This object (2004 VD17) looks promising. It has been classified as level 2 threat in the Torino scale for a some time.