[BAA-ebulletin 00679] 2012 LZ1: An unusually large NEO

[BAA electronic bulletins service]

An unusually large Near-Earth Object, 2012 LZ1 has just been discovered by 
Rob McNaught and colleagues on 2012 June 10/11 using the 0.5-m Uppsala 
Schmidt telescope at Siding Spring, Australia as reported in MPEC 2012-L30 
issued on June 12 09:30 UT.  See:
http://www.minorplanetcenter.net/mpec/K12/K12L30.html

The newly-discovered NEO is approximately 300-700 metres in size (H=19.7) 
and makes its closest approach of 0.036 AU (about 14 lunar-distances) on 
June 15.0 UT.  The object will be visible from the UK near closest approach 
rather low down in a south-eastly direction and may be best seen before dawn 
(around 01:00-02:00 UT) on Friday, June 15 as an asteroidal object, 
magnitude 13.9 or so, moving at an apparent speed of about 38 "/min at an 
altitude of roughly 25 degrees above the horizon.

Unusually too, although moving in an orbit inclined at 26 degrees, its 
motion is quite commensurate with that of the Earth at the moment and so the 
object will remain visible from the UK on many successive nights as it moves 
further northwards.  For example during the next ten days, the declination, 
brightness and apparent speed will be as follows:

June 14/15  Decl. -15  V=13.9  38"/min
June 15/16  Decl. +01  V=14.2  36 "/min
June 16/17  Decl. +13  V=14.6  30 "/min
June 17/18  Decl. +23  V=15.1  23 "/min
June 18/19  Decl. +31  V=15.6  18 "/min
June 19/20  Decl. +37  V=16.0  13 "/min
June 20/21  Decl. +42  V=16.4  10 "/min
June 21/22  Decl. +46  V=16.7  8 "/min
June 22/23  Decl. +49  V=17.0  7 "/min

Note that the summer solstice this year occurs on June 20 at 23h UT at which 
time this object will be visible from the UK in a westerly direction at an 
altitude of some 54 degrees.

Given its size and proximity to the Earth, 2012 LZ1 is the latest 
potentially hazardous asteroid (PHA) discovered.  Congratulations to Rob 
McNaught on this particular find which was conducted as part of the Siding 
Spring Survey; an NEO search program, the southern hemisphere counterpart of 
the Catalina Sky survey.
See:  http://www.mso.anu.edu.au/~rmn/

Sky coordinates for finding this new visitor to the Earth's neighbourhood 
can be obtained from the Minor Planet Center's ephemeris service at:
http://minorplanetcenter.net/iau/MPEph/MPEph.html
Remember to enter a suitable Observatory Code in the online form to achieve 
a satisfactory topocentric prediction.  For the UK, you might wish to use 
the Code for Greenwich namely '000'.

Observers are encouraged to report astrometry to the Minor Planet Center. 
Please report photometry to the nearest 0.01 mag to myself at the address 
below.  Thank you.

Richard Miles
Director, Asteroids and Remote Planets Section
British Astronomical Association
arps [at] britastro.org

2012 June 12