| 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 · 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
$$
M_a = (9.234 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.234 |
| n |
6.000 |
| gf |
0.938 |
| gb |
-0.857 |
| k |
1.000 |
| δ90 |
3.014 |
| 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) |
| 2026-03-26 00:00 |
13:00:24.67 |
-17:59:06.0 |
HIP 63552 |
15.07 |
| 2026-03-26 12:00 |
13:00:11.65 |
-17:57:52.4 |
HIP 63552 |
17.55 |
| 2026-03-27 00:00 |
12:59:58.58 |
-17:56:37.9 |
HIP 63552 |
20.29 |
| 2026-03-27 12:00 |
12:59:45.49 |
-17:55:22.6 |
HIP 63501 |
21.24 |
| 2026-03-28 00:00 |
12:59:32.36 |
-17:54:06.5 |
HIP 63501 |
22.44 |
| 2026-03-28 12:00 |
12:59:19.21 |
-17:52:49.5 |
HIP 63501 |
24.05 |
| 2026-03-29 00:00 |
12:59:06.02 |
-17:51:31.7 |
HIP 63501 |
26.00 |
| 2026-03-29 12:00 |
12:58:52.81 |
-17:50:13.1 |
HIP 63501 |
28.23 |
| 2026-03-30 00:00 |
12:58:39.58 |
-17:48:53.7 |
HIP 63248 |
29.49 |
| 2026-03-30 12:00 |
12:58:26.33 |
-17:47:33.6 |
HIP 63248 |
26.79 |
| 2026-03-31 00:00 |
12:58:13.06 |
-17:46:12.7 |
HIP 63248 |
24.25 |
| 2026-03-31 12:00 |
12:57:59.78 |
-17:44:51.0 |
HIP 63248 |
21.95 |
| 2026-04-01 00:00 |
12:57:46.48 |
-17:43:28.6 |
HIP 63248 |
19.97 |
| 2026-04-01 12:00 |
12:57:33.17 |
-17:42:05.4 |
HIP 63248 |
18.41 |
| 2026-04-02 00:00 |
12:57:19.85 |
-17:40:41.5 |
HIP 63248 |
17.41 |
| 2026-04-02 12:00 |
12:57:06.52 |
-17:39:16.9 |
HIP 63248 |
17.05 |
| 2026-04-03 00:00 |
12:56:53.18 |
-17:37:51.7 |
HIP 63248 |
17.38 |
| 2026-04-03 12:00 |
12:56:39.85 |
-17:36:25.7 |
HIP 63248 |
18.37 |
| 2026-04-04 00:00 |
12:56:26.51 |
-17:34:59.1 |
HIP 63248 |
19.93 |
| 2026-04-04 12:00 |
12:56:13.17 |
-17:33:31.8 |
HIP 63248 |
21.93 |
| 2026-04-05 00:00 |
12:55:59.84 |
-17:32:03.9 |
HIP 63248 |
24.27 |
| 2026-04-05 12:00 |
12:55:46.51 |
-17:30:35.3 |
HIP 63248 |
26.86 |
| 2026-04-06 00:00 |
12:55:33.19 |
-17:29:06.1 |
HIP 63248 |
29.64 |
| 2026-04-06 12:00 |
12:55:19.88 |
-17:27:36.3 |
HIP 63248 |
32.55 |
| 2026-04-07 00:00 |
12:55:06.58 |
-17:26:05.9 |
HIP 63248 |
35.57 |
| 2026-04-07 12:00 |
12:54:53.29 |
-17:24:35.0 |
HIP 63134 |
35.72 |
| 2026-04-08 00:00 |
12:54:40.03 |
-17:23:03.5 |
HIP 63134 |
36.14 |
| 2026-04-08 12:00 |
12:54:26.77 |
-17:21:31.4 |
HIP 63134 |
36.87 |
| 2026-04-09 00:00 |
12:54:13.54 |
-17:19:58.8 |
HIP 63134 |
37.92 |
| 2026-04-09 12:00 |
12:54:00.34 |
-17:18:25.7 |
HIP 63134 |
39.24 |
| 2026-04-10 00:00 |
12:53:47.15 |
-17:16:52.1 |
HIP 62735 |
39.90 |
| 2026-04-10 12:00 |
12:53:34.00 |
-17:15:17.9 |
HIP 62735 |
37.94 |
| 2026-04-11 00:00 |
12:53:20.87 |
-17:13:43.3 |
HIP 62735 |
36.23 |
| 2026-04-11 12:00 |
12:53:07.78 |
-17:12:08.3 |
HIP 62735 |
34.80 |
| 2026-04-12 00:00 |
12:52:54.72 |
-17:10:32.8 |
HIP 62735 |
33.68 |
| 2026-04-12 12:00 |
12:52:41.69 |
-17:08:56.8 |
HIP 62735 |
32.91 |
| 2026-04-13 00:00 |
12:52:28.70 |
-17:07:20.5 |
HIP 62735 |
32.50 |
| 2026-04-13 12:00 |
12:52:15.75 |
-17:05:43.7 |
HIP 62735 |
32.48 |
| 2026-04-14 00:00 |
12:52:02.85 |
-17:04:06.6 |
HIP 62647 |
32.40 |
| 2026-04-14 12:00 |
12:51:49.99 |
-17:02:29.0 |
HIP 62647 |
31.01 |
| 2026-04-15 00:00 |
12:51:37.17 |
-17:00:51.2 |
HIP 62647 |
29.97 |
| 2026-04-15 12:00 |
12:51:24.40 |
-16:59:13.0 |
HIP 62647 |
29.31 |
| 2026-04-16 00:00 |
12:51:11.69 |
-16:57:34.4 |
HIP 62584 |
27.40 |