9P/Tempel 1
| Parameter |
Value |
| Designation |
9P/Tempel 1 |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2016-08-02T13:41:50.605440Z |
| Orbit solution date (soln_date, UTC) |
2025-12-29T09:30:51Z |
| Obs used |
3283 |
| NEO |
- |
| M1 |
12.900 |
| K1 |
9.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2016-03-23.0000000 |
| e |
0.50970283 |
| q (au) |
1.542540 |
| a (au) |
3.146134 |
| i (deg) |
10.473428 |
| Ω (om, deg) |
68.753575 |
| ω (w, deg) |
179.197275 |
| M (ma, deg) |
336.585444 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.814 + 4.498\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.814 |
| n |
4.498 |
| gf |
0.800 |
| gb |
-0.509 |
| k |
0.875 |
| δ90 |
3.601 |
| Parameter |
Symbol |
Range |
Description |
| Absolute magnitude at 1 AU from Sun and Earth |
H0 |
-5 to 20 |
Intrinsic brightness of the comet |
| Photometric slope parameter |
n |
2 to 6 |
Rate of brightness change with heliocentric distance |
| Forward scattering asymmetry factor |
gf |
0.8 to 1 |
Degree of forward scattering |
| Backward scattering asymmetry factor |
gb |
-1 to -0.5 |
Degree of backward scattering |
| Partitioning coefficient |
k |
0.8 to 1 |
Ratio between forward/backward scattering contributions |
| Dust-to-gas brightness ratio |
δ90 |
1 to 10 |
Relative contribution of dust scattering to gas emission |
Reference: EPSC-DPS2025-160
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
05:47:59.95 |
+29:41:24.5 |
HIP 27336 |
7.87 |
| 2026-02-03 12:00 |
05:47:46.38 |
+29:41:13.9 |
HIP 27336 |
5.00 |
| 2026-02-04 00:00 |
05:47:33.08 |
+29:41:02.9 |
HIP 27336 |
2.38 |
| 2026-02-04 12:00 |
05:47:20.05 |
+29:40:51.6 |
HIP 27336 |
1.74 |
| 2026-02-05 00:00 |
05:47:07.29 |
+29:40:40.1 |
HIP 27336 |
4.00 |
| 2026-02-05 12:00 |
05:46:54.80 |
+29:40:28.3 |
HIP 27336 |
6.60 |
| 2026-02-06 00:00 |
05:46:42.58 |
+29:40:16.2 |
HIP 27336 |
9.22 |
| 2026-02-06 12:00 |
05:46:30.63 |
+29:40:03.9 |
HIP 27336 |
11.79 |
| 2026-02-07 00:00 |
05:46:18.96 |
+29:39:51.3 |
HIP 27336 |
14.32 |
| 2026-02-07 12:00 |
05:46:07.57 |
+29:39:38.5 |
HIP 27336 |
16.79 |
| 2026-02-08 00:00 |
05:45:56.45 |
+29:39:25.4 |
HIP 27336 |
19.20 |
| 2026-02-08 12:00 |
05:45:45.62 |
+29:39:12.2 |
HIP 27172 |
21.50 |
| 2026-02-09 00:00 |
05:45:35.06 |
+29:38:58.7 |
HIP 27172 |
21.08 |
| 2026-02-09 12:00 |
05:45:24.78 |
+29:38:45.0 |
HIP 27039 |
19.42 |
| 2026-02-10 00:00 |
05:45:14.78 |
+29:38:31.1 |
HIP 27039 |
17.38 |
| 2026-02-10 12:00 |
05:45:05.06 |
+29:38:17.1 |
HIP 27039 |
15.45 |
| 2026-02-11 00:00 |
05:44:55.63 |
+29:38:02.9 |
HIP 27039 |
13.61 |
| 2026-02-11 12:00 |
05:44:46.48 |
+29:37:48.5 |
HIP 27039 |
11.90 |
| 2026-02-12 00:00 |
05:44:37.61 |
+29:37:34.0 |
HIP 27039 |
10.33 |
| 2026-02-12 12:00 |
05:44:29.03 |
+29:37:19.3 |
HIP 27039 |
8.94 |
| 2026-02-13 00:00 |
05:44:20.73 |
+29:37:04.4 |
HIP 27039 |
7.79 |
| 2026-02-13 12:00 |
05:44:12.72 |
+29:36:49.5 |
HIP 27039 |
6.95 |
| 2026-02-14 00:00 |
05:44:05.00 |
+29:36:34.4 |
HIP 27039 |
6.49 |
| 2026-02-14 12:00 |
05:43:57.56 |
+29:36:19.2 |
HIP 27039 |
6.43 |
| 2026-02-15 00:00 |
05:43:50.41 |
+29:36:03.9 |
HIP 27039 |
6.76 |
| 2026-02-15 12:00 |
05:43:43.55 |
+29:35:48.5 |
HIP 27039 |
7.36 |
| 2026-02-16 00:00 |
05:43:36.98 |
+29:35:33.0 |
HIP 27039 |
8.16 |
| 2026-02-16 12:00 |
05:43:30.69 |
+29:35:17.4 |
HIP 27039 |
9.07 |
| 2026-02-17 00:00 |
05:43:24.70 |
+29:35:01.7 |
HIP 27039 |
10.04 |
| 2026-02-17 12:00 |
05:43:18.99 |
+29:34:46.0 |
HIP 27039 |
11.02 |
| 2026-02-18 00:00 |
05:43:13.57 |
+29:34:30.1 |
HIP 26993 |
11.80 |
| 2026-02-18 12:00 |
05:43:08.44 |
+29:34:14.3 |
HIP 26993 |
12.55 |
| 2026-02-19 00:00 |
05:43:03.60 |
+29:33:58.4 |
HIP 26993 |
13.32 |
| 2026-02-19 12:00 |
05:42:59.05 |
+29:33:42.4 |
HIP 26875 |
12.92 |
| 2026-02-20 00:00 |
05:42:54.79 |
+29:33:26.4 |
HIP 26845 |
12.23 |
| 2026-02-20 12:00 |
05:42:50.81 |
+29:33:10.4 |
HIP 26845 |
11.34 |
| 2026-02-21 00:00 |
05:42:47.13 |
+29:32:54.3 |
HIP 26845 |
10.50 |
| 2026-02-21 12:00 |
05:42:43.73 |
+29:32:38.2 |
HIP 26845 |
9.73 |
| 2026-02-22 00:00 |
05:42:40.62 |
+29:32:22.1 |
HIP 26845 |
9.03 |
| 2026-02-22 12:00 |
05:42:37.80 |
+29:32:06.0 |
HIP 26845 |
8.39 |
| 2026-02-23 00:00 |
05:42:35.26 |
+29:31:49.9 |
HIP 26845 |
7.82 |
| 2026-02-23 12:00 |
05:42:33.01 |
+29:31:33.7 |
HIP 26845 |
7.32 |
| 2026-02-24 00:00 |
05:42:31.05 |
+29:31:17.6 |
HIP 26845 |
6.89 |