ACE Spacecraft Maneuvers






A list of time periods with high levels of nutation due to ACE Spacecraft Maneuvers.

The time periods listed have levels of spacecraft nutation which exceed the required .03 degrees as a result of maneuvers. The start times of the time periods are exact. However, the time span is an approximation (good to within +/- 10 minutes). The time spans are conservative estimates so that the nutation after the end of the span is definitely below 0.03 degrees.

This table will be updated periodically as we receive the information from the Flight Dynamics Facility at GSFC.

326 hours of high nutation out of 7408 total hours of data collected up to 1998-177. Nutation is below 0.03 degrees 95.6% of the time.

ACE spacecraft nutation due to maneuvers can be detected by plotting the time differences between successive spacecraft spin periods. The spin periods are calculated from the sunpulse times contained in ACE Level 1 data. Click here to access plots of these spin period perturbations,for each day of the mission.

The magnitude of the nutation can be calculated from the spin period perturbations as follows:

Nutation = 180 * Delta_P * tan(sun_angle)/(Pmax + Pmin)
where (Pmax + Pmin) usually equals ~24, since ACE spins at ~5rpm.

ACE High Nutation time periods

From                    To                      Span            Type of Maneuver

1997
Day 237  1600           Day 237  2200           6 hrs           Launch/Tip-off
Day 238  1412           Day 238  1712           3 hrs           MCC Burns
Day 239  2000           Day 240  0100           5 hrs           Attitude Reor
Day 245  1630           Day 245  2130           5 hrs           Attitude Reor
Day 250  1600           Day 250  2200           6 hrs           Engineering Burn
Day 256  1730           Day 257  0130           8 hrs           Orbit Shaping Maneuver (OSM) 1
Day 257  1600           Day 258  0400           12 hrs          OSM 2
Day 258  1630           Day 259  0330           11 hrs          OSM 3
Day 262  1630           Day 263  0230           10 hrs          OSM 4
Day 266  1530           Day 267  0130           10 hrs          OSM 5
Day 267  1544           Day 268  0144           10 hrs          OSM 6
Day 275  1730           Day 275  2030           3 hrs           Axial Trim Burn
Day 283  1815           Day 283  2315           5 hrs           Attitude Reor
Day 289  1645           Day 289  2045           4 hrs           Attitude Reor
Day 294  1914           Day 294  2314           4 hrs           Attitude Reor
Day 297  1445           Day 297  1845           4 hrs           Attitude Reor
Day 301  1500           Day 301  1900           5 hrs           Attitude Reor
Day 304  2100           Day 305  0100           5 hrs           Attitude Reor
Day 308  1500           Day 308  1900           5 hrs           Attitude Reor
Day 311  1440           Day 311  1840           5 hrs           Attitude Reor
Day 316  1530           Day 316  2030           5 hrs           Attitude Reor
Day 321  1615           Day 321  2115           5 hrs           Attitude Reor
Day 325  1540           Day 325  2040           5 hrs           Attitude Reor
Day 329  1549           Day 329  1949           4 hrs           Attitude Reor
Day 333  1339           Day 333  1739           4 hrs           Attitude Reor
Day 336  1645           Day 336  2045           4 hrs           Attitude Reor
Day 339  2022           Day 340  0030           4 hrs           Attitude Reor
Day 343  1756           Day 344  0450           11 hrs          Halo Orbit Insertion (HOI) 1
Day 344  1835           Day 345  0430           10 hrs          HOI 2
Day 345  1755           Day 346  0300           9 hrs           HOI 3
Day 346  1750           Day 347  0450           11 hrs          HOI 4
Day 351  2217           Day 352  0117           3 hrs           Attitude Reor
Day 353  1730           Day 353  2330           6 hrs           HOI Trim, Attitude Reor
Day 357  1338           Day 357  1735           4 hrs           Attitude Reor
Day 361  1345           Day 361  1745           4 hrs           Attitude Reor
Day 365  1434           Day 365  1834           4 hrs           Attitude Reor

1998
Day 005  1800           Day 005  2200           4 hrs           Attitude Reor
Day 009  1758           Day 009  2058           3 hrs           Attitude Reor
Day 015  1415           Day 015  1815           4 hrs           Attitude Reor, Station-Keeping
Day 021  1714           Day 021  2014           3 hrs           Attitude Reor
Day 027  1502           Day 027  1802           3 hrs           Attitude Reor
Day 034  1717           Day 034  2017           3 hrs           Attitude Reor
Day 042  1504           Day 042  1804           3 hrs           Attitude Reor
Day 051  2000           Day 052  0000           4 hrs           Attitude Reor, Station-Keeping
Day 058  1651           Day 058  1951           3 hrs           Attitude Reor
Day 068  1339           Day 068  1639           3 hrs           Attitude Reor
Day 077  1410           Day 077  1710           3 hrs           Attitude Reor
Day 084  1440           Day 084  1940           5 hrs           Att Reor, Spin Up, Station-Keeping 
Day 091  1546           Day 091  1846           3 hrs           Attitude Reor
Day 098  1402           Day 098  1702           3 hrs           Attitude Reor
Day 105  1414           Day 105  1714           3 hrs           Attitude Reor
Day 111  1424           Day 111  1724           3 hrs           Attitude Reor
Day 117  1516           Day 117  1816           3 hrs           Attitude Reor
Day 121  1530           Day 121  1930           4 hrs           Attitude Reor, Station-Keeping
Day 126  1517           Day 126  1817           3 hrs           Attitude Reor
Day 131  1416           Day 131  1816           4 hrs           Attitude Reor
Day 135  1520           Day 135  1820           3 hrs           Attitude Reor
Day 139  1721           Day 139  2021           3 hrs           Attitude Reor
Day 142  1414           Day 142  1714           3 hrs           Attitude Reor
Day 146  1609           Day 146  1909           3 hrs           Attitude Reor
Day 149  1422           Day 149  1722           3 hrs           Attitude Reor
Day 153  1817           Day 153  2117           3 hrs           Attitude Reor
Day 156  1315           Day 156  1615           3 hrs           Attitude Reor
Day 163  1541           Day 163  2241           7 hrs           Attitude Reors (2 segmnts)
Day 168  1712           Day 168  2112           4 hrs           Attitude Reor, Station-Keeping
Day 173  1429           Day 173  1929           5 hrs           Attitude Reor (2 segmnts)
Day 177  1444           Day 177  1744           3 hrs           Attitude Reor


From here on, we only list the start-times of the maneuvers, and
we only list the maneuver-type for maneuvers which are not normal
attitude maneuvers.

YEAR DOY START-TIME(UT)  TYPE-OF-MANEUVER

1998 183 13:42           
1998 188 14:18
1998 195 17:17
1998 202 17:59           Station-Keeping
1998 209 17:31
1998 218 13:35
1998 226 17:46
1998 236 14:16
1998 246 17:03           Station-Keeping
1998 257 13:56
1998 266 15:32
1998 274 16:22
1998 282 16:18
1998 289 15:11
1998 295 13:47
1998 300 15:39
1998 306 13:47
1998 310 16:22
1998 315 15:52           Station-Keeping
1998 320 14:38
1998 323 17:06
1998 327 14:20
1998 329 13:53
1998 334 14:24
1998 337 17:43
1998 343 14:11
1998 349 19:56
1998 356 18:48
1998 363 14:39
1999 006 15:14
1999 014 14:37           Station-Keeping, Spin Correction
1999 022 17:53
1999 033 15:29
1999 043 16:13
1999 055 15:15
1999 067 16:32
1999 077 16:22
1999 085 16:12
1999 092 15:54
1999 099 15:35           Station-Keeping
1999 106 15:17
1999 113 15:38
1999 120 16:24
1999 127 15:51
1999 133 15:23
1999 139 15:24
1999 145 16:00
1999 152 16:50
1999 152 21:08
1999 159 16:07
1999 166 19:28
1999 174 17:59
1999 183 19:06           Station-Keeping
1999 190 15:49
1999 197 16:22
1999 207 14:42
1999 216 15:24
1999 229 16:01
1999 242 16:00
1999 252 15:24
1999 260 14:58
1999 270 14:42
1999 277 14:26           Station-Keeping, Spin Correction
1999 278 14:27
1999 285 15:25
1999 291 13:38
1999 295 15:19
1999 300 16:27
1999 306 16:27
1999 312 17:12
1999 316 17:24
1999 320 21:39           Lisajous RLP Z-axis Control
1999 322 19:25
1999 328 14:42
1999 334 17:36
1999 341 17:48           Station-Keeping
1999 348 17:52
1999 355 17:50
1999 362 17:46
2000 006 14:30
2000 014 18:31
2000 021 17:26
2000 028 17:20
2000 039 15:12
2000 048 14:52           Lissajous RLP Z-axis Control, Spin Correction
2000 049 19:03           Station-Keeping
2000 059 15:51
2000 068 15:54
2000 069 15:52           Station-Keeping
2000 077 15:52
2000 084 15:45
2000 091 15:16
2000 097 15:45
2000 103 15:20
2000 109 16:05
2000 115 15:07
2000 121 15:45
2000 124 15:11
2000 130 16:03
2000 136 16:20
2000 143 16:09
2000 147 16:25
2000 154 19:11
2000 161 16:14
2000 168 14:56
2000 175 16:11
2000 182 17:23           Station-Keeping
2000 189 16:41
2000 200 18:42
2000 210 16:48
2000 222 16:32
2000 230 15:31           Lisajous RLP Z-axis Control
2000 231 17:10
2000 242 14:57
2000 243 15:04           Lisajous RLP Z-axis Control
2000 252 17:25
2000 258 16:21
2000 265 16:33
2000 272 17:35
2000 279 15:44
2000 286 16:08
2000 292 15:52
2000 298 16:35
2000 304 17:28
2000 308 18:24
2000 314 17:56
2000 320 17:16
2000 327 17:36
2000 333 17:59
2000 340 18:41
2000 347 18:14
2000 356 17:54
2000 363 17:28
2001 004 18:10           Station-Keeping
2001 016 17:47
2001 026 17:31
2001 037 18:28           Lisajous RLP Z-axis Control plus spin correction
2001 038 15:37           Lisajous RLP Z-axis Control plus station-keeping
2001 047 15:59
2001 054 15:57           Station-Keeping
2001 061 15:42
2001 068 15:36
2001 075 16:14
2001 079 15:54
2001 085 15:45
2001 087 17:51
2001 094 16:46
2001 100 17:42
2001 106 16:32
2001 110 16:15
2001 116 15:44
2001 122 16:41
2001 129 17:13
2001 136 16:10
2001 144 16:53           Station-Keeping
2001 152 15:56
2001 159 17:09
2001 166 17:28
2001 173 15:14
2001 179 16:08
2001 187 15:31
2001 194 15:01
2001 205 14:35           Lisajous RLP Z-axis Control
2001 206 14:59           Station-Keeping
2001 222 15:16           Station-Keeping
2001 229 14:19
2001 236 14:53
2001 243 16:06
2001 250 15:30
2001 257 15:04
2001 263 14:09
2001 269 14:24
2001 275 15:48
2001 281 15:54
2001 285 13:54
2001 291 16:14
2001 297 16:37
2001 303 16:53
2001 310 17:14
2001 317 17:28
2001 325 14:22
2001 333 14:21           Station-Keeping
2001 341 14:15
2001 347 14:08
2001 355 14:07
2002 002 16:51
2002 014 14:22
2002 025 16:45
2002 036 15:59
2002 045 15:51
2002 053 15:47
2002 060 15:56
2002 067 16:03
2002 073 16:07
2002 078 16:06
2002 081 15:26
2002 087 16:27
2002 094 16:47
2002 101 18:46           Station-Keeping
2002 108 16:15
2002 116 16:43
2002 126 17:35
2002 137 17:00
2002 148 16:22
2002 157 14:14
2002 171 15:23
2002 177 15:02
2002 193 15:05
2002 211 15:27           Station-Keeping
2002 225 14:18
2002 235 15:28
2002 242 15:27
2002 249 15:39
2002 256 14:44
2002 263 16:12
2002 270 15:48
2002 277 14:40
2002 284 17:12
2002 294 18:07
2002 305 13:41           Station-Keeping
2002 317 17:43
2002 330 19:24
2002 339 18:27
2002 353 20:33
2002 357 16:46
2003 009 16:34
2003 024 16:08
2003 037 16:23
2003 045 16:01           Station-Keeping
2003 055 16:29
2003 062 15:55
2003 066 16:29
2003 071 22:30
2003 080 16:53
2003 087 15:48
2003 094 16:06
2003 104 18:28
2003 115 16:22
2003 127 16:36
2003 142 16:25
2003 150 17:47
2003 157 15:54
2003 174 17:42           Station-Keeping
2003 192 14:24
2003 206 16:31
2003 219 14:28
2003 230 14:36
2003 239 15:44
2003 245 15:54
2003 251 15:06
2003 259 15:26
2003 267 16:15
2003 276 16:42
2003 286 14:17
2003 297 17:24
2003 310 17:25
2003 325 17:10           Station-Keeping
2003 337 17:21           Station-Keeping
2003 352 13:46
2004 002 18:18
2004 016 16:04
2004 028 16:00
2004 037 16:39
2004 047 16:27
2004 054 17:04
2004 057 22:01           Station-Keeping
2004 061 16:19
2004 068 16:16
2004 076 16:59
2004 085 16:23
2004 093 15:44
2004 105 16:00
2004 118 16:05
2004 133 16:56
2004 148 14:51           Station-Keeping
2004 162 14:22           Spin Control
2004 177 16:06
2004 191 13:53
2004 204 14:03
2004 215 14:30
2004 225 14:36
2004 233 14:53           Lissajous orbit Station-Keeping
2004 240 14:25
2004 247 15:59
2004 254 16:33           Excessive nutation due to incorrectly executed maneuver
2004 261 13:17
2004 271 15:56
2004 282 14:33
2004 295 18:28
2004 310 15:16
2004 327 16:47
2004 341 16:36           Station-Keeping
2004 355 16:50
2005 004 16:14
2005 014 16:06
2005 024 13:57
2005 034 16:10
2005 042 14:33
2005 049 16:39
2005 056 16:35
2005 062 16:37
2005 070 15:10
2005 076 15:08           Station-Keeping
2005 087 16:50
2005 098 17:19
2005 112 17:06
2005 129 16:05
2005 145 17:35
2005 154 14:37
2005 166 16:06
2005 180 13:57
2005 192 13:47
2005 203 15:21
2005 213 16:00
2005 222 14:57


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Last Updated: Aug 30, 2005

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