| Parameter |
Value |
| Designation |
485P/Sheppard-Tholen |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2005-10-10T02:23:33.267840Z |
| Orbit solution date (soln_date, UTC) |
2024-10-10T17:21:52Z |
| Obs used |
12 |
| NEO |
- |
| M1 |
6.600 |
| K1 |
19.250 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2006-01-02T08:50:54.816000Z |
| Discovery magnitude (MPC) |
20.30 V |
| Discovery observatory (MPC) |
G96 · University of Arizona Mt. Lemmon Survey |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2009-04-12.0000000 |
| e |
0.41586197 |
| q (au) |
3.995838 |
| a (au) |
6.840572 |
| i (deg) |
10.009723 |
| Ω (om, deg) |
261.841751 |
| ω (w, deg) |
195.918921 |
| M (ma, deg) |
70.508521 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.238 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.238 |
| n |
6.000 |
| gf |
0.937 |
| gb |
-0.857 |
| k |
1.000 |
| δ90 |
2.963 |
| 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 |
13:20:09.30 |
-16:06:15.5 |
HIP 64993 |
34.53 |
| 2026-09-20 12:00 |
13:20:28.99 |
-16:07:48.5 |
HIP 65086 |
34.42 |
| 2026-09-21 00:00 |
13:20:48.70 |
-16:09:21.8 |
HIP 65086 |
33.29 |
| 2026-09-21 12:00 |
13:21:08.44 |
-16:10:55.5 |
HIP 65310 |
32.29 |
| 2026-09-22 00:00 |
13:21:28.22 |
-16:12:29.4 |
HIP 65310 |
29.06 |
| 2026-09-22 12:00 |
13:21:48.03 |
-16:14:03.6 |
HIP 65310 |
26.40 |
| 2026-09-23 00:00 |
13:22:07.86 |
-16:15:38.1 |
HIP 65310 |
24.48 |
| 2026-09-23 12:00 |
13:22:27.73 |
-16:17:12.9 |
HIP 65310 |
23.50 |
| 2026-09-24 00:00 |
13:22:47.63 |
-16:18:48.0 |
HIP 65310 |
23.58 |
| 2026-09-24 12:00 |
13:23:07.55 |
-16:20:23.4 |
HIP 65344 |
20.52 |
| 2026-09-25 00:00 |
13:23:27.50 |
-16:21:59.0 |
HIP 65344 |
18.03 |
| 2026-09-25 12:00 |
13:23:47.48 |
-16:23:34.9 |
HIP 65344 |
16.72 |
| 2026-09-26 00:00 |
13:24:07.48 |
-16:25:11.1 |
HIP 65344 |
16.89 |
| 2026-09-26 12:00 |
13:24:27.51 |
-16:26:47.6 |
HIP 65344 |
18.49 |
| 2026-09-27 00:00 |
13:24:47.57 |
-16:28:24.3 |
HIP 65344 |
21.21 |
| 2026-09-27 12:00 |
13:25:07.65 |
-16:30:01.3 |
HIP 65552 |
20.12 |
| 2026-09-28 00:00 |
13:25:27.76 |
-16:31:38.6 |
HIP 65552 |
15.21 |
| 2026-09-28 12:00 |
13:25:47.89 |
-16:33:16.1 |
HIP 65552 |
10.46 |
| 2026-09-29 00:00 |
13:26:08.05 |
-16:34:53.8 |
HIP 65552 |
6.26 |
| 2026-09-29 12:00 |
13:26:28.23 |
-16:36:31.8 |
HIP 65552 |
4.57 |
| 2026-09-30 00:00 |
13:26:48.43 |
-16:38:10.1 |
HIP 65552 |
7.40 |
| 2026-09-30 12:00 |
13:27:08.65 |
-16:39:48.6 |
HIP 65552 |
11.87 |
| 2026-10-01 00:00 |
13:27:28.90 |
-16:41:27.3 |
HIP 65552 |
16.71 |
| 2026-10-01 12:00 |
13:27:49.17 |
-16:43:06.2 |
HIP 65552 |
21.69 |
| 2026-10-02 00:00 |
13:28:09.45 |
-16:44:45.4 |
HIP 65552 |
26.73 |
| 2026-10-02 12:00 |
13:28:29.76 |
-16:46:24.8 |
HIP 65552 |
31.80 |
| 2026-10-03 00:00 |
13:28:50.09 |
-16:48:04.5 |
HIP 65552 |
36.90 |
| 2026-10-03 12:00 |
13:29:10.44 |
-16:49:44.3 |
HIP 65939 |
39.78 |
| 2026-10-04 00:00 |
13:29:30.81 |
-16:51:24.4 |
HIP 65939 |
37.87 |
| 2026-10-04 12:00 |
13:29:51.19 |
-16:53:04.6 |
HIP 65939 |
36.60 |
| 2026-10-05 00:00 |
13:30:11.60 |
-16:54:45.1 |
HIP 65939 |
36.03 |
| 2026-10-05 12:00 |
13:30:32.02 |
-16:56:25.8 |
HIP 65939 |
36.19 |
| 2026-10-06 00:00 |
13:30:52.46 |
-16:58:06.7 |
HIP 65939 |
37.09 |
| 2026-10-06 12:00 |
13:31:12.91 |
-16:59:47.8 |
HIP 65939 |
38.67 |
| 2026-10-07 00:00 |
13:31:33.38 |
-17:01:29.0 |
HIP 65939 |
40.86 |
| 2026-10-07 12:00 |
13:31:53.86 |
-17:03:10.5 |
HIP 66231 |
40.54 |
| 2026-10-08 00:00 |
13:32:14.36 |
-17:04:52.1 |
HIP 66231 |
35.40 |
| 2026-10-08 12:00 |
13:32:34.87 |
-17:06:33.9 |
HIP 66231 |
30.28 |
| 2026-10-09 00:00 |
13:32:55.40 |
-17:08:15.9 |
HIP 66231 |
25.18 |
| 2026-10-09 12:00 |
13:33:15.93 |
-17:09:58.1 |
HIP 66231 |
20.11 |
| 2026-10-10 00:00 |
13:33:36.48 |
-17:11:40.4 |
HIP 66231 |
15.13 |
| 2026-10-10 12:00 |
13:33:57.04 |
-17:13:22.9 |
HIP 66231 |
10.37 |
| 2026-10-11 00:00 |
13:34:17.61 |
-17:15:05.5 |
HIP 66231 |
6.32 |