The NEA (Near-Earth asteroid) 2005 YU55 passed
very close to Earth on 8 November 2011 at 23.28 UT, at a
distance of only 324600 km (0.85 lunar distances). More info
can be found on wikipedia.
I've imaged it about 20 hours after the minimum distance, being in the best conditions to be observed from Italy. It was of magnitude 12 and was moving at about 0.7 "/s toward East. I've imaged it from my observatory with the piggybacked Newton telescope and a Lodestar CCD camera (usually used as a guider). More technical data are in the table below. Here are some still and animated results.
Average of 76 images of 5 s exp, from 21.24 to 21.45 UT, selected 1 every 3 of a series
Composition of 350 images of 10 s exp, aligned and tracked on the asteroid (sligtly elongated dot in the center), from 22.21 to 23.24 UT
I've imaged it about 20 hours after the minimum distance, being in the best conditions to be observed from Italy. It was of magnitude 12 and was moving at about 0.7 "/s toward East. I've imaged it from my observatory with the piggybacked Newton telescope and a Lodestar CCD camera (usually used as a guider). More technical data are in the table below. Here are some still and animated results.
Average of 76 images of 5 s exp, from 21.24 to 21.45 UT, selected 1 every 3 of a series
Video of the movement of
the asteroid: stars fixed. 270 images of 5 s exp, from
21.21 to 21.46 UT
Video of the movement of
the asteroid: asteroid fixed. 350 images of 10 s exp,
from 22.21 to 23.24 UT
Composition of 350 images of 10 s exp, aligned and tracked on the asteroid (sligtly elongated dot in the center), from 22.21 to 23.24 UT
Ephemeris of that night,
computed for my B39 observatory, from MPC:
K05Y55U
Date UT R.A. (J2000) Decl. Delta r El. Ph. V Sky Motion Object Sun Moon Uncertainty info
h m s "/min P.A. Azi. Alt. Alt. Phase Dist. Alt. 3-sig/" P.A.
2011 11 09 160000 01 08 28.0 +18 50 04 0.0058 0.996 154.1 25.8 11.9 70.36 092.1 264 +20 -01 0.99 013 +09 7 027.1 / Map / Offsets
2011 11 09 170000 01 13 08.3 +18 47 21 0.0061 0.996 155.2 24.7 12.0 62.60 092.6 273 +30 -11 0.99 012 +20 6 027.4 / Map / Offsets
2011 11 09 180000 01 17 18.0 +18 44 23 0.0064 0.996 156.1 23.7 12.1 55.95 093.2 284 +40 -21 0.99 012 +30 6 027.7 / Map / Offsets
2011 11 09 190000 01 21 01.7 +18 41 11 0.0067 0.997 157.0 22.9 12.1 50.30 093.8 298 +49 -32 0.99 011 +40 6 028.0 / Map / Offsets
2011 11 09 200000 01 24 23.1 +18 37 46 0.0071 0.997 157.7 22.1 12.2 45.52 094.4 316 +57 -42 0.99 011 +49 6 028.2 / Map / Offsets
2011 11 09 210000 01 27 25.9 +18 34 09 0.0074 0.997 158.4 21.4 12.3 41.51 095.1 341 +62 -51 0.99 011 +56 5 028.4 / Map / Offsets
2011 11 09 220000 01 30 13.0 +18 30 24 0.0077 0.998 159.0 20.8 12.3 38.18 095.8 011 +63 -58 0.99 011 +61 5 028.5 / Map / Offsets
2011 11 09 230000 01 32 47.2 +18 26 31 0.0080 0.998 159.6 20.2 12.4 35.42 096.4 037 +58 -61 0.99 010 +60 5 028.7 / Map / Offsets
2011 11 10 000000 01 35 10.6 +18 22 34 0.0083 0.998 160.1 19.7 12.5 33.15 096.9 057 +51 -59 0.99 010 +55 5 028.8 / Map / Offsets
2011 11 10 010000 01 37 25.2 +18 18 36 0.0086 0.999 160.6 19.2 12.6 31.27 097.3 072 +42 -53 0.99 010 +47 5 028.9 / Map / Offsets
2011 11 10 020000 01 39 32.4 +18 14 39 0.0090 0.999 161.1 18.7 12.6 29.70 097.6 084 +32 -44 0.99 010 +38 4 029.0 / Map / Offsets
2011 11 10 030000 01 41 33.5 +18 10 48 0.0093 0.999 161.5 18.3 12.7 28.36 097.7 094 +22 -34 1.00 010 +28 4 029.1 / Map / Offsets
2011 11 10 040000 01 43 29.3 +18 07 06 0.010 1.000 161.9 17.9 12.7 27.18 097.7 104 +11 -24 1.00 010 +18 4 029.2 / Map / Offsets
2011 11 10 050000 01 45 20.4 +18 03 34 0.010 1.000 162.4 17.5 12.8 26.10 097.5 114 +02 -13 1.00 010 +08 4 029.2 / Map / Offsets
My astrometric measurements,
sent to MPC:
COD B39
OBS L. Comolli
MEA L. Comolli
TEL 0.31-m f/5.0 Newtonian reflector + CCD
ACK MPCReport file updated 2011.11.11 19:35:27
NET UCAC-3
K05Y55U KC2011 11 09.84266 01 25 10.03 +18 37 22.3 11.9 R B39
K05Y55U KC2011 11 09.84400 01 25 16.05 +18 37 15.6 11.8 R B39
K05Y55U KC2011 11 09.84441 01 25 17.89 +18 37 13.9 12.0 R B39
K05Y55U KC2011 11 09.84615 01 25 25.66 +18 37 04.1 11.9 R B39
K05Y55U KC2011 11 09.84652 01 25 27.29 +18 37 02.5 11.8 R B39
K05Y55U KC2011 11 09.84726 01 25 30.60 +18 36 58.4 11.7 R B39
K05Y55U KC2011 11 09.84814 01 25 34.50 +18 36 54.3 11.9 R B39
K05Y55U KC2011 11 09.84929 01 25 39.61 +18 36 48.0 11.8 R B39
K05Y55U KC2011 11 09.85120 01 25 48.06 +18 36 37.8 11.9 R B39
K05Y55U KC2011 11 09.85315 01 25 56.60 +18 36 27.7 12.0 R B39
K05Y55U KC2011 11 09.87854 01 27 45.02 +18 34 13.4 12.0 R B39
K05Y55U KC2011 11 09.89286 01 28 43.57 +18 32 56.4 12.0 R B39
K05Y55U KC2011 11 09.89703 01 29 00.32 +18 32 33.3 11.9 R B39
K05Y55U KC2011 11 09.90093 01 29 15.82 +18 32 11.9 12.0 R B39
K05Y55U KC2011 11 09.90412 01 29 28.45 +18 31 54.3 12.0 R B39
K05Y55U KC2011 11 09.91565 01 30 13.35 +18 30 51.3 11.9 R B39
K05Y55U KC2011 11 09.91917 01 30 26.82 +18 30 31.7 11.8 R B39
K05Y55U KC2011 11 09.92510 01 30 49.36 +18 29 58.7 11.7 R B39
K05Y55U KC2011 11 09.92781 01 30 59.58 +18 29 44.0 12.1 R B39
K05Y55U KC2011 11 09.93257 01 31 17.39 +18 29 17.1 12.0 R B39
K05Y55U KC2011 11 09.94506 01 32 03.44 +18 28 06.9 12.0 R B39
K05Y55U KC2011 11 09.94696 01 32 10.35 +18 27 56.1 11.9 R B39
K05Y55U KC2011 11 09.94883 01 32 17.12 +18 27 45.7 11.9 R B39
K05Y55U KC2011 11 09.95155 01 32 26.93 +18 27 30.2 11.8 R B39
K05Y55U KC2011 11 09.95461 01 32 37.94 +18 27 12.8 11.9 R B39
K05Y55U KC2011 11 09.95887 01 32 53.16 +18 26 48.7 11.9 R B39
K05Y55U KC2011 11 09.96136 01 33 02.00 +18 26 34.6 11.9 R B39
K05Y55U KC2011 11 09.97515 01 33 50.26 +18 25 15.8 11.9 R B39
