Index to observations received from ARPS
members
Observations received FROM ARPS MEMBERS
July and August 2009
2009 has provided some
exceptional statistics for Great Shefford so far, more usable nights (103)
& more hours used (455) in the first 6 months of the year since the
observatory was commissioned in 2002, beating the previous best Jan-June (2005)
by 10%. Hopefully the last half of the year will be equally good.
June started with the close fly-by of Apollo 2009 KL8, passing Earth at 5 Lunar
Distances (LD) on June 2nd. That night it was moving at 60"/min and fading
fast, from 19th to 20th mag. during the course of the night. Two nights before,
even though about 30% further away it was about 1.5 magnitudes brighter because
of its smaller phase angle and I followed it that night for 1h 45 minutes to
try and determine its rotation period. That turned out to be just 2 mins 41
seconds, varying by 0.75 magnitudes and it had managed to complete 32 rotations
while I was observing it!
Another close approach occurred on June 24 at
72091 C2009 06 01.00658 16 18
24.88 -11 26 16.2 18.7 R J95 = MBA
K01F90E
C2009 06 26.00834814 03 29.39 +28 30 45.9 15.8 R J95 = Apollo
K01F90E
C2009 06 26.01232114 03 38.83 +28 29 02.4 14.7 R J95
K01F90E
C2009 06 26.01644114 03 48.63 +28 27 14.7 14.7 R J95
K01F90E
C2009 06 26.97029314 45 40.11 +20 13 55.8 13.9 R J95
K01F90E
C2009 06 26.97366414 45 49.31 +20 11 50.2 14.8 R J95
K01F90E
C2009 06 26.97702314 45 58.50 +20 09 44.8 13.9 R J95
K01F90E
C2009 06 27.98141315 35 38.90 +08 17 12.6 13.2 R J95
K01F90E
C2009 06 27.98425415 35 47.32 +08 14 58.3 13.3 R J95
K01F90E
C2009 06 27.98729715 35 56.36 +08 12 34.2 14.2 R J95
K05N63J
C2009 06 30.02133 19 15 11.82 +34 07 30.1 J95 = Aten
K05N63J
C2009 06 30.05797 19 14 58.12 +34 04 38.7 19.5 R J95
K05N63J C2009
06 30.07606 19 14 51.22 +34 03 14.7 J95
K09K08L C2009 06 01.05872819 51
47.48 +65 49 06.1 18.4 R J95 = Apollo
K09K08L C2009 06 01.06096519 52
19.64 +65 50 14.0 18.6 R J95
K09K08L C2009 06 01.06374519 52
59.65 +65 51 37.5 18.6 R J95
K09K08L C2009 06 01.94829823 42
51.03 +61 37 42.4
J95
K09K08L C2009 06 01.95514023 44
11.77 +61 31 21.7 19.4 R J95
K09K08L C2009 06 01.96221523 45 34.19
+61 24 45.6 19.3 R J95
K09K08L C2009 06 02.05271700 02
02.73 +59 57 19.3
J95
K09K08L C2009 06 02.06048800 03
21.93 +59 49 32.5 20.1 R J95
K09K08L C2009 06 02.06788000 04
36.47 +59 42 07.2
J95
K09K21V C2009 06 01.00658 16 18
52.32 -11 27 22.6 20.3 R J95 = Apollo
K09K22J C2009 06 02.03068 19 47
20.76 -13 58 13.5
J95 = AST329 = Amor
K09K22J C2009 06 02.03942 19 47
22.42 -13 57 56.2
J95
K09K22J C2009 06 02.04533 19 47
23.47 -13 57 44.8 19.2 R J95
K09K22K C2009 06 01.97058 16 41
04.30 -15 56 20.8
J95 = A01732 = MBA
K09K22K C2009 06 01.97755 16 41
03.80 -15 56 11.0
J95
K09K22K C2009 06 01.98530 16 41
03.29 -15 56 00.3 18.1 R J95
K09L00A C2009 06 01.93143 16 31
57.24 +00 09 35.7
J95 = Apollo
K09L00A C2009 06 01.93625 16 31
59.58 +00 10 50.6
J95
K09L00A C2009 06 01.94097 16 32
01.82 +00 12 03.9 19.0 R J95
K09L00B C2009 06 01.91395 16 35
37.38 -01 40 30.8
J95 = 9L05FE9 = Mars-crossing Asteroid
K09L00B C2009 06 01.92390 16 35
36.13 -01 41 17.9 18.9 R J95
K09L00D C2009 06 04.06613 17 42
36.33 +34 26 03.4
J95 = Aten
K09L00D C2009 06 04.07050 17 42
33.28 +34 25 59.9
J95
K09L00D C2009 06 04.07484 17 42
30.38 +34 25 56.6 20.5 R J95
K09L00E C2009 06 04.08055 17 59
35.95 +30 54 15.7
J95 = Apollo
K09L00E
C2009 06 04.08456 17 59 36.49 +30 53 50.0 J95
K09L00E
C2009 06 04.09000 17 59 37.19 +30 53 15.0 19.5 R J95
K09L00E
C2009 06 08.00928 18 16 00.29 +18 54 31.9 J95
K09L00E
C2009 06 08.01236 18 16 01.24 +18 53 34.7 J95
K09L00E
C2009 06 08.01549 18 16 02.18 +18 52 36.9 J95
K09L00E
C2009 06 08.02798 18 16 06.13 +18 48 46.3 18.0 R J95
K09L00Q
C2009 06 11.92622 15 57 42.17 +09 16 13.3 J95 = Apollo
K09L00Q C2009 06 11.93661 15 57 36.87 +09 17
12.5 J95
K09L00Q
C2009 06 11.94195 15 57 34.14 +09 17 42.3 18.8 R J95
K09L00Q
C2009 06 17.91685 14 41 23.76 +22 12 16.7 J95
K09L00Q
C2009 06 17.92008 14 41 19.99 +22 12 48.8 J95
K09L00Q
C2009 06 17.92325 14 41 16.27 +22 13 20.2 18.3 R J95
K09L00Q
C2009 06 18.92111 14 20 39.83 +25 03 18.8 J95
K09L00Q
C2009 06 18.92311 14 20 37.17 +25 03 39.4 J95
K09L00Q
C2009 06 18.92522 14 20 34.26 +25 04 00.9 18.6 R J95
K09L00Q
C2009 06 20.96494 13 28 08.72 +30 55 49.1 J95
K09L00Q
C2009 06 20.96627 13 28 06.37 +30 56 02.7 J95
K09L00Q C2009
06 20.96767 13 28 03.85 +30 56 16.2
19.2 R J95
K09L00S C2009 06 16.00824 16 59
55.95 -01 34 18.4
J95 = Apollo
K09L00S C2009 06 16.01249 16 59
55.18 -01 34 06.6 J95
K09L00S C2009 06 16.01678 16 59
54.44 -01 33 54.9
J95
K09L00S C2009 06 16.02015 16 59
53.83 -01 33 46.0 18.5 R J95
K09L00S C2009 06 16.93528 16 57
15.83 -00 52 27.9
J95
K09L00S
C2009 06 16.93943 16 57 15.11 -00 52 17.0 J95
K09L00S C2009 06 16.94358 16 57
14.36 -00 52 05.7 18.7 R J95
K09L02V C2009 06 15.98163 16 45
46.59 +25 30 25.9 J95
= 9L9F4AF = Apollo
K09L02V C2009 06 15.98954 16 45
43.38 +25 32 09.7
J95
K09L02V C2009 06 15.99969 16 45
39.35 +25 34 20.9 20.6 R J95
K09L02V C2009 06 16.94841 16 39
18.21 +29 00 36.6 J95
K09L02V C2009 06 16.95073 16 39
17.14 +29 01 07.2
J95
K09L02V C2009 06 16.95486 16 39
15.30 +29 02 00.2 20.3 R J95
K09L02V C2009 06 18.99667 16 23
44.35 +36 25 15.4
J95
K09L02V
C2009 06 19.00533 16 23 40.04 +36 27 06.4 J95
K09L02V C2009 06 19.01074 16 23
37.18 +36 28 16.5 20.6 R J95
K09M00A C2009 06 16.91199 17 28
07.46 +10 19 12.6
J95 = 9M9FBAF = Amor
K09M00A C2009 06 16.91702 17 28
07.43 +10 18 57.6
J95
K09M00A C2009 06 16.92074 17 28
07.38 +10 18 44.0 19.1 R J95
K09M00A C2009 06 17.95219 17 28
20.33 +09 19 50.7
J95
K09M00A C2009 06 17.95489 17 28 20.33 +09 19
40.9 J95
K09M00A C2009 06 17.95757 17 28
20.32 +09 19 31.1 18.6 R J95
K09M00A C2009 06 28.05769 17 33
21.45 -09 23 44.5
J95
K09M00A C2009 06 28.06001 17 33
21.55 -09 24 10.5
J95
K09M00A C2009 06 28.06196 17 33
21.62 -09 24 32.2 17.9 R J95
K09M00B C2009 06 17.93164 17 17
42.07 -04 56 55.2
J95 = 9MA02B8 = Mars-crossing Asteroid
K09M00B C2009 06 17.94372 17 17
41.20 -04 56 43.5 19.9 R J95
K09M00D C2009 06 18.06369 20 59 17.54 +09 07
12.6 J95 = 9MA032E =
Amor
K09M00D
C2009 06 18.07460 20 59 22.19 +09 06 37.5 20.5 R J95
K09M00O BC2009 06 19.08175 23 25 08.52 +10
04 33.2 J95 =
9MA0438 = MBA
K09M00O BC2009 06 19.08867 23 25 08.94 +10
04 34.1 19.8 R J95
K09M00S C2009
06 24.02988 17 29 21.15 +01 43 58.0 J95 = Apollo
K09M00S C2009 06 24.03593 17 29
20.62 +01 44 00.1 20.4 R J95
K09M00U C2009 06 21.92017 15 41
26.63 +09 55 04.5
J95 = 9M07B99 = Apollo
K09M00U C2009 06 21.92117 15 41
25.59 +09 55 18.7 J95
K09M00U C2009 06 21.92216 15 41
24.49 +09 55 31.6
J95
K09M00U C2009 06 21.92493 15 41
21.54 +09 56 08.5 17.7 R J95
K09M00U C2009 06 22.92795715 16
45.75 +15 30 50.1 17.2 R J95
K09M00U C2009 06 22.93003715 16
40.78 +15 31 50.5 17.0 R J95
K09M00U C2009 06 22.93242615 16
35.06 +15 33 00.0 17.1 R J95
K09M00U C2009 06 22.99060515 14
11.95 +16 01 56.0 17.2 R J95
K09M00U
C2009 06 22.99270915 14 06.65 +16 03 00.1 16.8 R J95
K09M00U C2009 06 22.99682215 13
56.26 +16 05 06.0 16.7 R J95
K09M00U C2009 06 23.04567715 11
50.38 +16 30 33.3 16.8 R J95
K09M00U C2009 06 23.04813915 11
43.93 +16 31 52.0 17.1 R J95
K09M00U C2009 06 23.05250015 11
32.45 +16 34 11.6 16.8 R J95
K09M00U C2009 06 23.90154814 07
07.88 +28 40 56.0 16.6 R J95
K09M00U C2009 06 23.90413014 06
46.33 +28 44 09.1 17.2 R J95
K09M00U C2009 06 23.90613714 06
29.54 +28 46 40.0 16.6 R J95
K09M00U C2009 06 23.95757813 59
00.99 +29 52 10.7 16.2 R J95
K09M00U C2009 06 23.95881213 58
49.80 +29 53 46.5 16.1 R J95
K09M00U C2009 06 23.95998413 58
39.15 +29 55 17.5 16.1 R J95
K09M00U C2009 06 23.98925913 54
06.85 +30 33 35.5 16.4 R J95
K09M00U C2009 06 23.99056713 53
54.41 +30 35 19.1 16.5 R J95
K09M00U C2009 06 23.99187613 53
41.94 +30 37 02.6 16.9 R J95
K09M00U C2009 06 24.01785513 49
29.12 +31 11 38.5 16.4 R J95
K09M00U C2009 06 24.01976013 49
10.18 +31 14 12.1 16.7 R J95
K09M00U C2009 06 24.02481913 48
19.75 +31 21 00.2 17.5 R J95
K09M00X
C2009 06 22.01273 16 29 53.56 +11 53 45.7 J95 = 9MA0B64 = Amor
K09M00X C2009
06 22.01661 16 29 53.42 +11 53 13.4 J95
K09M00X C2009 06 22.02127 16 29 53.42 +11 52
33.3 19.1 R J95
K09M06Z C2009 06 29.95515 20 03
59.45 -05 32 49.1
J95 = Amor
K09M06Z C2009 06 29.96847 20 04
00.83 -05 32 58.2 19.1 R J95
K09M07K C2009 06 28.06606 23 47
41.64 +35 15 54.5
J95 = 9M08B8B = Mars-crossing Asteroid
K09M07K C2009 06 28.06879 23 47
42.00 +35 15 59.3
J95
K09M07K C2009 06 28.07151 23 47 42.32
+35 16 04.3 19.8 R J95
K09M07J IC2009 06 28.07722 20 47 40.30 +06
37 52.5 J95 =
9MA324A = MBA
K09M07J IC2009 06 28.08583 20 47 40.07 +06 37
47.1 20.3 R J95
Dave Briggs, J69
OBS David Briggs
TEL 0.40-m f/4.57 Newtonian reflector + CCD
AC2
G3697
C2009 08 17.91991 16 39 48.97 +31 45 49.5 16.0 C J69
G3697
C2009 08 17.92079 16 39 50.94 +31 45 47.8 16.2 C J69
G3697
C2009 08 17.92168 16 39 52.87 +31 45 46.3 16.0 C J69
G3697
C2009 08 17.92933 16 40 09.71 +31 45 31.5 16.2 C J69
G3697 C2009
08 17.93161 16 40 14.68 +31 45 27.5
16.0 C J69
L7390 C2009 08 17.99075 17 03 54.62 +23 33
19.1 15.6 C J69
L7390 C2009 08 17.99163 17 03 55.50 +23 33
00.3 15.5 C J69
L7390 C2009 08 18.00080 17 04 05.16 +23 29
49.0 15.7 C J69
L7390
C2009 08 18.00169 17 04 06.02 +23 29 30.6 15.8 C J69
L7390
C2009 08 18.00257 17 04 06.97 +23 29 11.8 15.8 C J69
----- end -----
OBS David Briggs
TEL 0.40-m f/4.57 Newtonian reflector + CCD
AC2
K09Q09J
C2009 08 24.93591 20 22 27.15 +12 55 40.8 16.3 C J69
K09Q09J
C2009 08 24.93796 20 22 27.66 +12 55 27.1 16.2 C J69
K09Q09K
C2009 08 24.94830 21 58 08.74 +17 38 04.4 17.3 C J69
K09Q09K C2009
08 24.95022 21 58 09.88 +17 38 02.9
17.6 C J69
K09Q09K C2009 08 24.95214 21 58
11.03 +17 38 02.5 17.7 C J69
----- end -----
OBS David Briggs
TEL 0.40-m f/4.57 Newtonian reflector + CCD
AC2
9Q18D04
C2009 08 28.88475 21 08 08.20 +06 48 21.4 16.4 C J69
9Q18D04
C2009 08 28.88564 21 08 11.01 +06 48 34.8 16.8 C J69
9Q18D04
C2009 08 28.88652 21 08 13.83 +06 48 48.6 16.8 C J69
9Q18D04
C2009 08 28.88740 21 08 16.60 +06 49 01.9 17.5 C J69
9Q18D04
C2009 08 28.88829 21 08 19.44 +06 49 15.4 18.3 C J69
----- end -----
OBS David Briggs
TEL 0.40-m f/4.57 Newtonian reflector + CCD
AC2
K09Q09K C2009 08 28.93660 00 11
20.06 +12 52 41.0 16.7 C J69
K09Q09K C2009 08 28.93679 00 11
21.25 +12 52 37.6 16.9 C J69
K09Q09K C2009 08 28.93698 00 11
22.24 +12 52 34.8 16.9 C J69
K09Q09K C2009 08 28.93718 00 11
23.24 +12 52 31.9 16.4 C J69
K09Q09K C2009 08 28.93736 00 11
24.27 +12 52 28.3 16.2 C J69
----- end -----
Alan Cahill, J94
OBS A.E. Cahill
TEL 0.3-m f/4.0 Schmidt-Cassegrain + CCD
AC2
31650
C2009 07 29.93275 20 02 22.32 +01 19 31.7 16.6 C
J94
31650 C2009 07 29.94063 20 02 21.99 +01 19
28.7 16.5 C
J94
31650 C2009 07 29.95373 20 02 21.32 +01 19
23.5 16.5 C
J94
51637 C2009 07 29.92655 20 02 11.51 +02 03
32.4 16.9 C
J94
51637 C2009 07 29.93865 20 02 10.91 +02 03
32.9 16.8 C
J94
51637 C2009 07 29.94958 20 02 10.28 +02 03
32.7 16.7 C
J94
----- end -----
OBS A.E. Cahill
TEL 0.3-m f/4.0 Schmidt-Cassegrain + CCD
AC2
38516
C2009 08 17.90825 21 55 09.64 +10 44 37.3 15.4 C J94
38516
C2009 08 17.92133 21 55 09.08 +10 44 31.8 15.0 C J94
38516 C2009
08 17.93750 21 55 08.40 +10 44 25.0
14.9 C J94
A9414
C2009 08 17.89978 21 48 57.53 +10 26 37.9 16.3 C J94
A9414
C2009 08 17.91597 21 48 56.57 +10 26 40.3 16.5 C J94
A9414
C2009 08 17.93277 21 48 55.58 +10 26 42.6 16.3 C J94
----- end -----
John Fletcher, J93
433 Eros
Unusual
17274 NEO.
0.2AU from home planet.
OBS John Fletcher
TEL 0.25-m f/5.5 Schmidt-Cassegrain + CCD
AC2
00433 C2009 08 01.98208 23 05 36.74 +03 48
37.1 12.4 V
J93
00433 C2009 08 01.98597 23 05 36.54 +03 48
39.0 12.3 V
J93
00433 C2009 08 01.98986 23 05 36.35 +03 48
40.8 12.4 V
J93
17274 C2009 08 01.99683 20 19 22.20 -18 11
22.3 14.2 V
J93
17274 C2009 08 01.99877 20 19 22.38 -18 11
17.4 14.2 V
J93
17274
C2009 08 02.00072 20 19 22.54 -18 11 13.3 14.2 V
J93
----- end -----
Eros 433 Unusual
17274 NEO 0.1au from home planet.
OBS John Fletcher
TEL 0.25-m f/5.5 Schmidt-Cassegrain + CCD
AC2
00433 C2009 08 15.92914 22 49 19.03 +05 25
23.8 12.0 V J93
00433 C2009 08 15.93140 22 49 18.83 +05 25
24.3 12.0 V J93
00433 C2009 08 15.93366 22 49 18.64 +05 25
25.3 12.0 V J93
17274 C2009 08 15.93793 20 47 37.15 -08 23
10.2 14.2 V J93
17274 C2009 08 15.93951 20 47 37.34 -08 23
06.0 14.2 V J93
17274 C2009 08 15.94111 20 47 37.53 -08 23
01.9 14.2 V J93
----- end -----
Eros 433 Unusual
17274 NEO 0.1au from home planet.
OBS John Fletcher
TEL 0.25-m f/5.5 Schmidt-Cassegrain + CCD
AC2
00433 C2009 08 17.94976 22 46 14.33 +05 35
09.9 11.7 V J93
00433 C2009 08 17.95198 22 46 14.11 +05 35
10.6 11.7 V J93
00433 C2009 08 17.95421 22 46 13.90 +05 35
10.9 11.7 V J93
17274 C2009 08 17.95840 20 52 10.80 -06 54
55.9 14.2 V J93
17274 C2009 08 17.96065 20 52 11.11 -06 54
50.5 14.2 V J93
17274 C2009 08 17.96291 20 52 11.38 -06 54
45.0 14.3 V J93
----- end -----
Eros 433 Unusual
17274 Near Earth Asteroid.
OBS John Fletcher
TEL 0.25-m f/5.5 Schmidt-Cassegrain + CCD
AC2
00433 C2009 08 20.95238 22 41 23.23 +05 47
23.1 11.7 V J93
00433 C2009 08 20.95458 22 41 23.01 +05 47
23.7 11.8 V J93
00433 C2009 08 20.95677 22 41 22.80 +05 47
24.1 11.8 V J93
17274 C2009 08 20.96822 20 59 08.78 -04 45
35.6 14.5 V J93
17274 C2009 08 20.97045 20 59 09.09 -04 45
29.8 14.5 V J93
17274 C2009 08 20.97269 20 59 09.37 -04 45
24.3 14.5 V J93
----- end -----
Eros 433 Unusual
17274 Near Earth Asteroid.
OBS John Fletcher
TEL 0.25-m f/5.5 Schmidt-Cassegrain + CCD
AC2
00433 C2009 08 20.95238 22 41 23.23 +05 47
23.1 11.7 V J93
00433 C2009 08 20.95458 22 41 23.01 +05 47
23.7 11.8 V J93
00433 C2009 08 20.95677 22 41 22.80 +05 47
24.1 11.8 V J93
17274 C2009 08 20.96822 20 59 08.78 -04 45
35.6 14.5 V J93
17274 C2009 08 20.97045 20 59 09.09 -04 45
29.8 14.5 V J93
17274 C2009 08 20.97269 20 59 09.37 -04 45
24.3 14.5 V J93
----- end -----
Eros 433 Unusual
17274 Near Earth Asteroid.
OBS John Fletcher
TEL 0.25-m f/5.5 Schmidt-Cassegrain + CCD
AC2
00433 C2009 08 21.88554 22 39 49.35 +05 50
36.5 11.7 V J93
00433 C2009 08 21.88778 22 39 49.10 +05 50
36.9 11.6 V J93
00433 C2009 08 21.89001 22 39 48.88 +05 50
37.2 11.6 V J93
17274 C2009 08 21.89662 21 01 20.71 -04 06
27.6 14.4 V J93
17274 C2009 08 21.89818 21 01 20.94 -04 06
23.5 14.3 V
J93
17274 C2009 08 21.89975 21 01 21.16 -04 06
19.7 14.3 V J93
----- end -----
OBS R. Miles
TEL 2.0-m f/10.0 Ritchey-Chretien + CCD
AC2
K09N00L C2009 07 14.50327 22 51
09.15 +31 08 40.9 17.1 R
F65
K09N00L C2009 07 14.50475 22 51
08.96 +31 08 23.4 17.1 R
F65
K09N00L C2009 07 14.50773 22 51
08.57 +31 07 46.8 17.2 R
F65
K09N00L C2009 07 14.50851 22 51
08.48 +31 07 37.5 17.3 R
F65
K09N00L C2009 07 14.51229 22 51
07.96 +31 06 52.0 17.4 R
F65
K09N00L C2009 07 14.51321 22 51
07.83 +31 06 40.7 17.4 R
F65
K09N00L C2009 07 14.51833 22 51 07.17 +31 05
38.0 17.3 R
F65
----- end -----
OBS R. Miles
TEL 2.0-m f/10.0 Ritchey-Chretien + CCD
AC2
97GC002
C2009 07 17.55699520 32 47.71 +05 46 15.5 18.0 R
E10
97GC002
C2009 07 17.55813120 32 47.87 +05 46 16.3 17.9 R
E10
97GC002
C2009 07 17.55921020 32 48.01 +05 46 17.1 17.8 R
E10
97GC002
C2009 07 17.56060020 32 48.21 +05 46 18.2 17.9 R
E10
AST388
C2009 07 17.54955018 03 12.90 -24 20 48.8 19.4 R
E10
AST388
C2009 07 17.55080018 03 12.79 -24 20 49.6 19.3 R
E10
AST388
C2009 07 17.55201318 03 12.71 -24 20 49.9 19.4 R
E10
AST388
C2009 07 17.55323218 03 12.59 -24 20 50.4 19.1 R
E10
-----
end -----
OBS R. Miles
TEL 2.0-m f/10.0 Ritchey-Chretien + CCD
AC2
9Q15126
C2009 08 26.53771 23 55 08.58 -17 05 16.5 19.5 R
E10
9Q15126
C2009 08 26.54014 23 55 08.53 -17 05 18.9 19.4 R
E10
9Q15BC8
C2009 08 26.52297 22 49 47.21 -07 03 54.4 19.3 R
E10
9Q15BC8
C2009 08 26.52394 22 49 46.99 -07 03 53.0 19.4 R
E10
9Q15BC8
C2009 08 26.52488 22 49 46.77 -07 03 51.6 19.3 R
E10
-----
end -----
Photometry
The Apollo 2001 FE90 was also
observed towards the end of the month. Discovered in 2001 when it reached 18th
magnitude, this year it was predicted to brighten to mag. +13.3 as it sped from
north to south in the evening sky and was scheduled to be a RADAR target at
Goldstone and
The lightcurve derived from about 30 minutes of images taken on the evening of
27 June 2009 is shown, including a mosaic of the images from the same sessions,
showing the rise and fall in brightness of the Minor Planet as it trailed (from
left to right). As can be seen, the observations cover just a couple of minutes
less than one full rotation period.
Email dated 2009 July 14.
Dear FT Team,
Please find attached a copy of the composite
rotational lightcurve of the
small near-Earth asteroid, 2009 LE, which I've
produced based on images
taken during 15 sessions on the
plus the
TU-Darmstadt and Simon Langton Grammar following an
observing alert sent out
on June 10 courtesy of Alison.
The bottom line is that this object has a probable
rotation period of 14.64
hours, which makes it the SLOWEST known rotator for
objects around this size
range or smaller.
It rotates more than 1,000 times more slowly than last
year's record breaker, 2008 HJ.
We were lucky weatherwise in that there were four
consecutive clear nights
on
However, the photometric analysis was a major
undertaking and was made
possible by my using one extra observing session
(this time on the Faulkes
Telescope South) on June 23 to image 11 fields which
the asteroid passed
through during the various observing runs of June
12. Since the asteroid
was at a declination of -34 to -36 deg, it was possible to calibrate
the
stars along the path of the object when they were
high in the sky near the
zenith as seen from Siding Spring. In this way, using the other scope in
the southern hemisphere really helped bigtime
especially since the object
had been moving at about 52 arcsec/min and so
covered about 3 degrees of sky
in just a few hours on June 12. I should add that I took advantage of a
methodology developed by Brian Warner which enables
the brightness and
colors of ensembles of stars to be determined with
fair accuracy (+/-0.02
mag) by using the J and J-K data amassed by the
2MASS survey; probably the
most useful homogeneous 'all-sky' source of
photometric data which exists.
Not a bad result considering the object is only
about 70 meters across and
was almost 10 times the distance of the Moon from
the Earth during most of
the observing runs.
On June 9-10 it was also only about 20-30 degrees away
from a 93-97% illuminated Moon in the sky, which
made life difficult. [In
future, when dogged by a nearby bright Moon, it will
be better to image
through the Pan-STARR-Z filter to cut down the
brightness of the sky
background.]
Finally, I shall report some more astrometry for the June
10-12 period in due course.