| Parameter |
Value |
| Designation |
P/2005 S2 (Skiff) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2006-06-30T17:48:40.472640Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:52Z |
| Obs used |
90 |
| NEO |
- |
| M1 |
7.900 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2005-09-03.0000000 |
| e |
0.19670978 |
| q (au) |
6.398037 |
| a (au) |
7.964789 |
| i (deg) |
3.141049 |
| Ω (om, deg) |
161.272405 |
| ω (w, deg) |
229.933181 |
| M (ma, deg) |
346.813274 |
Magnitude
Scatter + Global Linear
$$
M_a = (2.987 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
2.987 |
| n |
6.000 |
| gf |
0.966 |
| gb |
-0.504 |
| k |
1.000 |
| δ90 |
9.678 |
| 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 |
22:12:12.77 |
-10:21:58.2 |
HIP 109643 |
7.28 |
| 2026-03-26 12:00 |
22:12:30.49 |
-10:20:22.5 |
HIP 109643 |
5.55 |
| 2026-03-27 00:00 |
22:12:48.16 |
-10:18:47.0 |
HIP 109643 |
7.18 |
| 2026-03-27 12:00 |
22:13:05.78 |
-10:17:11.7 |
HIP 109643 |
10.72 |
| 2026-03-28 00:00 |
22:13:23.35 |
-10:15:36.6 |
HIP 109643 |
14.85 |
| 2026-03-28 12:00 |
22:13:40.87 |
-10:14:01.7 |
HIP 109643 |
19.19 |
| 2026-03-29 00:00 |
22:13:58.34 |
-10:12:27.0 |
HIP 109895 |
23.28 |
| 2026-03-29 12:00 |
22:14:15.75 |
-10:10:52.5 |
HIP 109895 |
18.75 |
| 2026-03-30 00:00 |
22:14:33.11 |
-10:09:18.2 |
HIP 109895 |
14.25 |
| 2026-03-30 12:00 |
22:14:50.41 |
-10:07:44.1 |
HIP 109895 |
9.82 |
| 2026-03-31 00:00 |
22:15:07.66 |
-10:06:10.3 |
HIP 109895 |
5.58 |
| 2026-03-31 12:00 |
22:15:24.86 |
-10:04:36.7 |
HIP 109895 |
2.61 |
| 2026-04-01 00:00 |
22:15:42.00 |
-10:03:03.3 |
HIP 109895 |
4.80 |
| 2026-04-01 12:00 |
22:15:59.09 |
-10:01:30.1 |
HIP 109895 |
8.91 |
| 2026-04-02 00:00 |
22:16:16.11 |
-09:59:57.2 |
HIP 109895 |
13.25 |
| 2026-04-02 12:00 |
22:16:33.09 |
-09:58:24.5 |
HIP 109895 |
17.65 |
| 2026-04-03 00:00 |
22:16:50.00 |
-09:56:52.0 |
HIP 110077 |
19.30 |
| 2026-04-03 12:00 |
22:17:06.86 |
-09:55:19.8 |
HIP 110077 |
15.20 |
| 2026-04-04 00:00 |
22:17:23.65 |
-09:53:47.9 |
HIP 110077 |
11.36 |
| 2026-04-04 12:00 |
22:17:40.39 |
-09:52:16.1 |
HIP 110077 |
8.12 |
| 2026-04-05 00:00 |
22:17:57.07 |
-09:50:44.7 |
HIP 110077 |
6.46 |
| 2026-04-05 12:00 |
22:18:13.69 |
-09:49:13.5 |
HIP 110077 |
7.46 |
| 2026-04-06 00:00 |
22:18:30.25 |
-09:47:42.6 |
HIP 110077 |
10.37 |
| 2026-04-06 12:00 |
22:18:46.75 |
-09:46:11.9 |
HIP 110223 |
12.45 |
| 2026-04-07 00:00 |
22:19:03.18 |
-09:44:41.6 |
HIP 110223 |
8.92 |
| 2026-04-07 12:00 |
22:19:19.56 |
-09:43:11.5 |
HIP 110223 |
6.44 |
| 2026-04-08 00:00 |
22:19:35.87 |
-09:41:41.6 |
HIP 110223 |
6.36 |
| 2026-04-08 12:00 |
22:19:52.12 |
-09:40:12.1 |
HIP 110223 |
8.72 |
| 2026-04-09 00:00 |
22:20:08.30 |
-09:38:42.9 |
HIP 110223 |
12.15 |
| 2026-04-09 12:00 |
22:20:24.42 |
-09:37:13.9 |
HIP 110223 |
15.98 |
| 2026-04-10 00:00 |
22:20:40.47 |
-09:35:45.3 |
HIP 110223 |
19.95 |
| 2026-04-10 12:00 |
22:20:56.46 |
-09:34:16.9 |
HIP 110223 |
23.99 |
| 2026-04-11 00:00 |
22:21:12.38 |
-09:32:48.9 |
HIP 110223 |
28.07 |
| 2026-04-11 12:00 |
22:21:28.24 |
-09:31:21.2 |
HIP 110223 |
32.16 |
| 2026-04-12 00:00 |
22:21:44.03 |
-09:29:53.8 |
HIP 110223 |
36.25 |
| 2026-04-12 12:00 |
22:21:59.75 |
-09:28:26.7 |
HIP 110223 |
40.34 |
| 2026-04-13 00:00 |
22:22:15.40 |
-09:27:00.0 |
HIP 110607 |
38.98 |
| 2026-04-13 12:00 |
22:22:30.98 |
-09:25:33.5 |
HIP 110607 |
36.67 |
| 2026-04-14 00:00 |
22:22:46.49 |
-09:24:07.5 |
HIP 110607 |
34.70 |
| 2026-04-14 12:00 |
22:23:01.93 |
-09:22:41.7 |
HIP 110607 |
33.13 |
| 2026-04-15 00:00 |
22:23:17.30 |
-09:21:16.3 |
HIP 110607 |
32.00 |
| 2026-04-15 12:00 |
22:23:32.60 |
-09:19:51.3 |
HIP 110607 |
31.36 |
| 2026-04-16 00:00 |
22:23:47.82 |
-09:18:26.6 |
HIP 110607 |
31.23 |