Hello,
In the early evening of 14th June 2012, a few minutes after reading about the following exciting news on
Spaceweather:
“Newly-discovered asteroid 2012 LZ1 is flying past the Earth-Moon system today. At closest approach on June 14th (23:10 UT), the 500 meter-wide space rock will be 14 lunar distances (3.3 million miles) away. A team of astronomers led by Ernesto Guido photographed the incoming asteroid on June 13th”
I set up in the back garden, hoping that I would be able to record this rather large rocky object, discovered only some 2 days prior by R. H. McNaught from the Siding Spring Observatory using the 0.5-m Uppsala Schmidt telescope.
2012 LZ1 is a large Near-Earth Object (NEO) approximately 300-700 metres in size and it has been classified as a PHA (Potentially Hazardous Asteroid). PHA’s are asteroids larger than approximately 100m that can come closer to Earth than 0.05 AU.
Here is an 25 frame stack and animation showing the trail of 2012 LZ1. The rather wobbly trail is a bit of a puzzle to me right now, but is likely to have been caused by a combination of a quick and dirty set up, poor polar alignment and too short guide exposures (1 sec) which may have led to the mount chasing the seeing?
Details:- Tak Mewlon 180mm F12 with Tak x0.8 Reducer/Flattener.
- SBIG ST2000XM CCD
- 25 frames of 60 sec exposure each
- Field of View is approx. 22x17 arcmin
- Image scale is 1.66 arcsec/pixel
- Separate guide scope.
Cheers
Dennis
PS – the animation was generated from a median combined frame to remove the trail of 2012 LZ1. The trail frames were then blended in using CS5, to remove the background frame-to-frame variation to minimise the file size of the animated gif.