Radiation zone passages occur between the end of one orbit and the beginning of the next. During radiation zone passages, no Chandra observations are possible due to the high particle background and the need to protect ACIS. For observations which must be tightly constrained, observers may wish to check projected estimates of usable orbit intervals (and their unusable complement during the radiation zone).
The begin and end orbit times listed below are approximate but conservative projected estimates for the actual radiation zone exit and entry times, calculated as perigee times ± 10 hours. Actual segments of orbits useful for observations are likely to be somewhat longer, but should not be shorter than the times listed here. Perigee times become less accurate as time increases from the creation date. At one year after the creation date, the perigee times are expected to be about 10 minutes off from the actual perigee time.
The date/times are provided here in Calendar (UTC) format. To convert to other date formats, please see the Date Conversion Tool page.
Earlier orbital event times can be accessed on our archived orbits pages.
| Orbit | Begin Orbit | End Orbit |
|---|---|---|
| 2128 | 2015 Jan 01 15:46:30.32 | 2015 Jan 03 11:14:56.50 |
| 2129 | 2015 Jan 04 07:14:56.50 | 2015 Jan 06 02:43:05.23 |
| 2130 | 2015 Jan 06 22:43:05.23 | 2015 Jan 08 18:10:50.54 |
| 2131 | 2015 Jan 09 14:10:50.54 | 2015 Jan 11 09:38:58.62 |
| 2132 | 2015 Jan 12 05:38:58.62 | 2015 Jan 14 01:07:51.81 |
| 2133 | 2015 Jan 14 21:07:51.81 | 2015 Jan 16 16:37:27.03 |
| 2134 | 2015 Jan 17 12:37:27.03 | 2015 Jan 19 08:06:58.47 |
| 2135 | 2015 Jan 20 04:06:58.47 | 2015 Jan 21 23:35:15.80 |
| 2136 | 2015 Jan 22 19:35:15.80 | 2015 Jan 24 15:02:15.96 |
| 2137 | 2015 Jan 25 11:02:15.96 | 2015 Jan 27 06:29:32.52 |
| 2138 | 2015 Jan 28 02:29:32.52 | 2015 Jan 29 21:57:31.27 |
| 2139 | 2015 Jan 30 17:57:31.27 | 2015 Feb 01 13:25:26.90 |
| 2140 | 2015 Feb 02 09:25:26.90 | 2015 Feb 04 04:52:54.37 |
| 2141 | 2015 Feb 05 00:52:54.37 | 2015 Feb 06 20:20:30.75 |
| 2142 | 2015 Feb 07 16:20:30.75 | 2015 Feb 09 11:48:47.17 |
| 2143 | 2015 Feb 10 07:48:47.17 | 2015 Feb 12 03:17:46.05 |
| 2144 | 2015 Feb 12 23:17:46.05 | 2015 Feb 14 18:47:01.82 |
| 2145 | 2015 Feb 15 14:47:01.82 | 2015 Feb 17 10:15:29.30 |
| 2146 | 2015 Feb 18 06:15:29.30 | 2015 Feb 20 01:42:25.46 |
| 2147 | 2015 Feb 20 21:42:25.46 | 2015 Feb 22 17:09:00.72 |
| 2148 | 2015 Feb 23 13:09:00.72 | 2015 Feb 25 08:36:26.15 |
| 2149 | 2015 Feb 26 04:36:26.15 | 2015 Feb 28 00:04:07.71 |
| 2150 | 2015 Feb 28 20:04:07.71 | 2015 Mar 02 15:31:25.58 |
| 2151 | 2015 Mar 03 11:31:25.58 | 2015 Mar 05 06:58:45.18 |
| 2152 | 2015 Mar 06 02:58:45.18 | 2015 Mar 07 22:26:39.42 |
| 2153 | 2015 Mar 08 18:26:39.42 | 2015 Mar 10 13:55:21.81 |
| 2154 | 2015 Mar 11 09:55:21.81 | 2015 Mar 13 05:24:27.26 |
| 2155 | 2015 Mar 14 01:24:27.26 | 2015 Mar 15 20:53:13.89 |
| 2156 | 2015 Mar 16 16:53:13.89 | 2015 Mar 18 12:20:41.86 |
| 2157 | 2015 Mar 19 08:20:41.86 | 2015 Mar 21 03:47:12.53 |
| 2158 | 2015 Mar 21 23:47:12.53 | 2015 Mar 23 19:14:20.50 |
| 2159 | 2015 Mar 24 15:14:20.50 | 2015 Mar 26 10:42:03.00 |
| 2160 | 2015 Mar 27 06:42:03.00 | 2015 Mar 29 02:09:33.90 |
| 2161 | 2015 Mar 29 22:09:33.90 | 2015 Mar 31 17:37:00.35 |
| 2162 | 2015 Apr 01 13:37:00.35 | 2015 Apr 03 09:04:52.67 |
| 2163 | 2015 Apr 04 05:04:52.67 | 2015 Apr 06 00:33:36.03 |
| 2164 | 2015 Apr 06 20:33:36.03 | 2015 Apr 08 16:02:53.01 |
| 2165 | 2015 Apr 09 12:02:53.01 | 2015 Apr 11 07:32:01.67 |
| 2166 | 2015 Apr 12 03:32:01.67 | 2015 Apr 13 23:00:14.22 |
| 2167 | 2015 Apr 14 19:00:14.22 | 2015 Apr 16 14:27:15.77 |
| 2168 | 2015 Apr 17 10:27:15.77 | 2015 Apr 19 05:54:21.53 |
| 2169 | 2015 Apr 20 01:54:21.53 | 2015 Apr 21 21:22:11.89 |
| 2170 | 2015 Apr 22 17:22:11.89 | 2015 Apr 24 12:50:02.21 |
| 2171 | 2015 Apr 25 08:50:02.21 | 2015 Apr 27 04:17:41.76 |
| 2172 | 2015 Apr 28 00:17:41.76 | 2015 Apr 29 19:45:42.12 |
| 2173 | 2015 Apr 30 15:45:42.12 | 2015 May 02 11:14:28.29 |
| 2174 | 2015 May 03 07:14:28.29 | 2015 May 05 02:43:56.10 |
| 2175 | 2015 May 05 22:43:56.10 | 2015 May 07 18:13:31.05 |
| 2176 | 2015 May 08 14:13:31.05 | 2015 May 10 09:42:23.00 |
| 2177 | 2015 May 11 05:42:23.00 | 2015 May 13 01:10:05.52 |
| 2178 | 2015 May 13 21:10:05.52 | 2015 May 15 16:37:21.53 |
| 2179 | 2015 May 16 12:37:21.53 | 2015 May 18 08:05:18.52 |
| 2180 | 2015 May 19 04:05:18.52 | 2015 May 20 23:33:27.57 |
| 2181 | 2015 May 21 19:33:27.57 | 2015 May 23 15:01:20.62 |
| 2182 | 2015 May 24 11:01:20.62 | 2015 May 26 06:29:24.16 |
| 2183 | 2015 May 27 02:29:24.16 | 2015 May 28 21:58:09.27 |
| 2184 | 2015 May 29 17:58:09.27 | 2015 May 31 13:27:37.05 |
| 2185 | 2015 Jun 01 09:27:37.05 | 2015 Jun 03 04:57:25.59 |
| 2186 | 2015 Jun 04 00:57:25.59 | 2015 Jun 05 20:26:38.75 |
| 2187 | 2015 Jun 06 16:26:38.75 | 2015 Jun 08 11:54:43.60 |
| 2188 | 2015 Jun 09 07:54:43.60 | 2015 Jun 11 03:22:09.28 |
| 2189 | 2015 Jun 11 23:22:09.28 | 2015 Jun 13 18:49:57.56 |
| 2190 | 2015 Jun 14 14:49:57.56 | 2015 Jun 16 10:18:12.13 |
| 2191 | 2015 Jun 17 06:18:12.13 | 2015 Jun 19 01:46:06.56 |
| 2192 | 2015 Jun 19 21:46:06.56 | 2015 Jun 21 17:13:58.28 |
| 2193 | 2015 Jun 22 13:13:58.28 | 2015 Jun 24 08:42:20.86 |
| 2194 | 2015 Jun 25 04:42:20.86 | 2015 Jun 27 00:11:28.05 |
| 2195 | 2015 Jun 27 20:11:28.05 | 2015 Jun 29 15:41:02.76 |
| 2196 | 2015 Jun 30 11:41:02.76 | 2015 Jul 02 07:10:23.86 |
| 2197 | 2015 Jul 03 03:10:23.86 | 2015 Jul 04 22:38:38.38 |
| 2198 | 2015 Jul 05 18:38:38.38 | 2015 Jul 07 14:05:54.45 |
| 2199 | 2015 Jul 08 10:05:54.45 | 2015 Jul 10 05:33:18.66 |
| 2200 | 2015 Jul 11 01:33:18.66 | 2015 Jul 12 21:01:19.19 |
| 2201 | 2015 Jul 13 17:01:19.19 | 2015 Jul 15 12:29:09.81 |
| 2202 | 2015 Jul 16 08:29:09.81 | 2015 Jul 18 03:56:43.95 |
| 2203 | 2015 Jul 18 23:56:43.95 | 2015 Jul 20 19:24:42.29 |
| 2204 | 2015 Jul 21 15:24:42.29 | 2015 Jul 23 10:53:21.84 |
| 2205 | 2015 Jul 24 06:53:21.84 | 2015 Jul 26 02:22:33.25 |
| 2206 | 2015 Jul 26 22:22:33.25 | 2015 Jul 28 17:51:46.27 |
| 2207 | 2015 Jul 29 13:51:46.27 | 2015 Jul 31 09:20:08.17 |
| 2208 | 2015 Aug 01 05:20:08.17 | 2015 Aug 03 00:47:13.78 |
| 2209 | 2015 Aug 03 20:47:13.78 | 2015 Aug 05 16:14:08.54 |
| 2210 | 2015 Aug 06 12:14:08.54 | 2015 Aug 08 07:41:44.26 |
| 2211 | 2015 Aug 09 03:41:44.26 | 2015 Aug 10 23:09:23.23 |
| 2212 | 2015 Aug 11 19:09:23.23 | 2015 Aug 13 14:36:46.30 |
| 2213 | 2015 Aug 14 10:36:46.30 | 2015 Aug 16 06:04:18.21 |
| 2214 | 2015 Aug 17 02:04:18.21 | 2015 Aug 18 21:32:28.71 |
| 2215 | 2015 Aug 19 17:32:28.71 | 2015 Aug 21 13:01:17.16 |
| 2216 | 2015 Aug 22 09:01:17.16 | 2015 Aug 24 04:30:16.92 |
| 2217 | 2015 Aug 25 00:30:16.92 | 2015 Aug 26 19:58:46.99 |
| 2218 | 2015 Aug 27 15:58:46.99 | 2015 Aug 29 11:26:05.49 |
| 2219 | 2015 Aug 30 07:26:05.49 | 2015 Sep 01 02:52:37.41 |
| 2220 | 2015 Sep 01 22:52:37.41 | 2015 Sep 03 18:19:47.70 |
| 2221 | 2015 Sep 04 14:19:47.70 | 2015 Sep 06 09:47:18.68 |
| 2222 | 2015 Sep 07 05:47:18.68 | 2015 Sep 09 01:14:36.64 |
| 2223 | 2015 Sep 09 21:14:36.64 | 2015 Sep 11 16:42:02.13 |
| 2224 | 2015 Sep 12 12:42:02.13 | 2015 Sep 14 08:10:00.69 |
| 2225 | 2015 Sep 15 04:10:00.69 | 2015 Sep 16 23:38:40.19 |
| 2226 | 2015 Sep 17 19:38:40.19 | 2015 Sep 19 15:07:41.35 |
| 2227 | 2015 Sep 20 11:07:41.35 | 2015 Sep 22 06:36:29.71 |
| 2228 | 2015 Sep 23 02:36:29.71 | 2015 Sep 24 22:04:19.52 |
| 2229 | 2015 Sep 25 18:04:19.52 | 2015 Sep 27 13:31:05.74 |
| 2230 | 2015 Sep 28 09:31:05.74 | 2015 Sep 30 04:58:01.52 |
| 2231 | 2015 Oct 01 00:58:01.52 | 2015 Oct 02 20:25:33.36 |
| 2232 | 2015 Oct 03 16:25:33.36 | 2015 Oct 05 11:53:00.17 |
| 2233 | 2015 Oct 06 07:53:00.17 | 2015 Oct 08 03:20:31.23 |
| 2234 | 2015 Oct 08 23:20:31.23 | 2015 Oct 10 18:48:29.29 |
| 2235 | 2015 Oct 11 14:48:29.29 | 2015 Oct 13 10:17:10.74 |
| 2236 | 2015 Oct 14 06:17:10.74 | 2015 Oct 16 01:46:23.19 |
| 2237 | 2015 Oct 16 21:46:23.19 | 2015 Oct 18 17:15:30.67 |
| 2238 | 2015 Oct 19 13:15:30.67 | 2015 Oct 21 08:43:54.76 |
| 2239 | 2015 Oct 22 04:43:54.76 | 2015 Oct 24 00:11:17.60 |
| 2240 | 2015 Oct 24 20:11:17.60 | 2015 Oct 26 15:38:17.95 |
| 2241 | 2015 Oct 27 11:38:17.95 | 2015 Oct 29 07:05:54.72 |
| 2242 | 2015 Oct 30 03:05:54.72 | 2015 Oct 31 22:33:35.35 |
| 2243 | 2015 Nov 01 18:33:35.35 | 2015 Nov 03 14:01:14.68 |
| 2244 | 2015 Nov 04 10:01:14.68 | 2015 Nov 06 05:29:17.71 |
| 2245 | 2015 Nov 07 01:29:17.71 | 2015 Nov 08 20:58:03.54 |
| 2246 | 2015 Nov 09 16:58:03.54 | 2015 Nov 11 12:27:22.59 |
| 2247 | 2015 Nov 12 08:27:22.59 | 2015 Nov 14 03:56:47.85 |
| 2248 | 2015 Nov 14 23:56:47.85 | 2015 Nov 16 19:25:42.96 |
| 2249 | 2015 Nov 17 15:25:42.96 | 2015 Nov 19 10:53:37.75 |
| 2250 | 2015 Nov 20 06:53:37.75 | 2015 Nov 22 02:20:59.01 |
| 2251 | 2015 Nov 22 22:20:59.01 | 2015 Nov 24 17:48:34.76 |
| 2252 | 2015 Nov 25 13:48:34.76 | 2015 Nov 27 09:16:28.67 |
| 2253 | 2015 Nov 28 05:16:28.67 | 2015 Nov 30 00:44:09.86 |
| 2254 | 2015 Nov 30 20:44:09.86 | 2015 Dec 02 16:12:05.59 |
| 2255 | 2015 Dec 03 12:12:05.59 | 2015 Dec 05 07:40:41.19 |
| 2256 | 2015 Dec 06 03:40:41.19 | 2015 Dec 07 23:09:54.40 |
| 2257 | 2015 Dec 08 19:09:54.40 | 2015 Dec 10 14:39:23.95 |
| 2258 | 2015 Dec 11 10:39:23.95 | 2015 Dec 13 06:08:26.80 |
| 2259 | 2015 Dec 14 02:08:26.80 | 2015 Dec 15 21:36:35.42 |
| 2260 | 2015 Dec 16 17:36:35.42 | 2015 Dec 18 13:03:59.23 |
| 2261 | 2015 Dec 19 09:03:59.23 | 2015 Dec 21 04:31:22.81 |
| 2262 | 2015 Dec 22 00:31:22.81 | 2015 Dec 23 19:59:11.25 |
| 2263 | 2015 Dec 24 15:59:11.25 | 2015 Dec 26 11:26:49.50 |
| 2264 | 2015 Dec 27 07:26:49.50 | 2015 Dec 29 02:54:22.32 |
| 2265 | 2015 Dec 29 22:54:22.32 | 2015 Dec 31 18:22:33.79 |
| 2266 | 2016 Jan 01 14:22:33.79 | -- |
Last modified: 12/14/16
