| Parameter |
Value |
| Designation |
P/2009 T2 (La Sagra) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2010-01-12T20:11:46.766400Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:35Z |
| Obs used |
882 |
| NEO |
- |
| M1 |
13.800 |
| K1 |
10.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2009-11-18.0000000 |
| e |
0.76899059 |
| q (au) |
1.754750 |
| a (au) |
7.596009 |
| i (deg) |
28.106386 |
| Ω (om, deg) |
215.985632 |
| ω (w, deg) |
215.470914 |
| M (ma, deg) |
357.371046 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.467 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.467 |
| n |
6.000 |
| gf |
0.800 |
| gb |
-0.867 |
| k |
0.998 |
| δ90 |
1.000 |
| 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) |
| 2026-09-20 00:00 |
17:51:51.79 |
+00:37:06.1 |
HIP 87432 |
28.94 |
| 2026-09-20 12:00 |
17:51:53.39 |
+00:36:05.1 |
HIP 87272 |
29.57 |
| 2026-09-21 00:00 |
17:51:55.08 |
+00:35:04.2 |
HIP 87272 |
29.83 |
| 2026-09-21 12:00 |
17:51:56.86 |
+00:34:03.3 |
HIP 87272 |
30.14 |
| 2026-09-22 00:00 |
17:51:58.74 |
+00:33:02.5 |
HIP 87272 |
30.51 |
| 2026-09-22 12:00 |
17:52:00.71 |
+00:32:01.7 |
HIP 87272 |
30.94 |
| 2026-09-23 00:00 |
17:52:02.77 |
+00:31:01.0 |
HIP 87272 |
31.43 |
| 2026-09-23 12:00 |
17:52:04.93 |
+00:30:00.4 |
HIP 87272 |
31.98 |
| 2026-09-24 00:00 |
17:52:07.18 |
+00:28:59.9 |
HIP 87637 |
32.27 |
| 2026-09-24 12:00 |
17:52:09.52 |
+00:27:59.4 |
HIP 87521 |
32.04 |
| 2026-09-25 00:00 |
17:52:11.96 |
+00:26:59.0 |
HIP 87521 |
30.89 |
| 2026-09-25 12:00 |
17:52:14.49 |
+00:25:58.8 |
HIP 87521 |
29.74 |
| 2026-09-26 00:00 |
17:52:17.11 |
+00:24:58.6 |
HIP 87521 |
28.58 |
| 2026-09-26 12:00 |
17:52:19.83 |
+00:23:58.4 |
HIP 87521 |
27.42 |
| 2026-09-27 00:00 |
17:52:22.63 |
+00:22:58.4 |
HIP 87521 |
26.27 |
| 2026-09-27 12:00 |
17:52:25.53 |
+00:21:58.5 |
HIP 87521 |
25.11 |
| 2026-09-28 00:00 |
17:52:28.52 |
+00:20:58.8 |
HIP 87521 |
23.96 |
| 2026-09-28 12:00 |
17:52:31.60 |
+00:19:59.1 |
HIP 87521 |
22.81 |
| 2026-09-29 00:00 |
17:52:34.77 |
+00:18:59.5 |
HIP 87521 |
21.67 |
| 2026-09-29 12:00 |
17:52:38.03 |
+00:18:00.1 |
HIP 87521 |
20.55 |
| 2026-09-30 00:00 |
17:52:41.39 |
+00:17:00.8 |
HIP 87521 |
19.44 |
| 2026-09-30 12:00 |
17:52:44.83 |
+00:16:01.6 |
HIP 87521 |
18.36 |
| 2026-10-01 00:00 |
17:52:48.37 |
+00:15:02.6 |
HIP 87521 |
17.32 |
| 2026-10-01 12:00 |
17:52:51.99 |
+00:14:03.7 |
HIP 87521 |
16.31 |
| 2026-10-02 00:00 |
17:52:55.71 |
+00:13:04.9 |
HIP 87521 |
15.37 |
| 2026-10-02 12:00 |
17:52:59.51 |
+00:12:06.3 |
HIP 87521 |
14.49 |
| 2026-10-03 00:00 |
17:53:03.41 |
+00:11:07.8 |
HIP 87521 |
13.69 |
| 2026-10-03 12:00 |
17:53:07.39 |
+00:10:09.5 |
HIP 87521 |
13.00 |
| 2026-10-04 00:00 |
17:53:11.47 |
+00:09:11.4 |
HIP 87521 |
12.45 |
| 2026-10-04 12:00 |
17:53:15.63 |
+00:08:13.4 |
HIP 87521 |
12.04 |
| 2026-10-05 00:00 |
17:53:19.88 |
+00:07:15.6 |
HIP 87521 |
11.81 |
| 2026-10-05 12:00 |
17:53:24.22 |
+00:06:18.0 |
HIP 87521 |
11.77 |
| 2026-10-06 00:00 |
17:53:28.65 |
+00:05:20.5 |
HIP 87521 |
11.93 |
| 2026-10-06 12:00 |
17:53:33.17 |
+00:04:23.2 |
HIP 87521 |
12.28 |
| 2026-10-07 00:00 |
17:53:37.77 |
+00:03:26.2 |
HIP 87521 |
12.81 |
| 2026-10-07 12:00 |
17:53:42.46 |
+00:02:29.3 |
HIP 87521 |
13.51 |
| 2026-10-08 00:00 |
17:53:47.24 |
+00:01:32.6 |
HIP 87521 |
14.35 |
| 2026-10-08 12:00 |
17:53:52.11 |
+00:00:36.1 |
HIP 87521 |
15.33 |
| 2026-10-09 00:00 |
17:53:57.06 |
-00:00:20.2 |
HIP 87521 |
16.41 |
| 2026-10-09 12:00 |
17:54:02.10 |
-00:01:16.2 |
HIP 87521 |
17.59 |
| 2026-10-10 00:00 |
17:54:07.23 |
-00:02:12.1 |
HIP 87521 |
18.84 |
| 2026-10-10 12:00 |
17:54:12.44 |
-00:03:07.7 |
HIP 87521 |
20.16 |
| 2026-10-11 00:00 |
17:54:17.74 |
-00:04:03.1 |
HIP 87521 |
21.54 |