| Parameter |
Value |
| Designation |
140P/Bowell-Skiff |
| Type |
P |
| Perihelion (tp_cal, UTC) |
1999-05-14T19:29:10.665600Z |
| Orbit solution date (soln_date, UTC) |
- |
| Obs used |
- |
| NEO |
- |
| M1 |
11.500 |
| K1 |
15.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1999-05-22.0000000 |
| e |
0.69176166 |
| q (au) |
1.971877 |
| a (au) |
6.397248 |
| i (deg) |
3.835828 |
| Ω (om, deg) |
343.456457 |
| ω (w, deg) |
173.086771 |
| M (ma, deg) |
0.437851 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.912 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.912 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
10.000 |
| 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 |
23:35:08.07 |
-01:52:22.1 |
HIP 116359 |
23.12 |
| 2026-09-20 12:00 |
23:34:57.98 |
-01:53:24.8 |
HIP 116359 |
23.50 |
| 2026-09-21 00:00 |
23:34:47.89 |
-01:54:27.5 |
HIP 116359 |
24.19 |
| 2026-09-21 12:00 |
23:34:37.81 |
-01:55:30.1 |
HIP 116290 |
23.77 |
| 2026-09-22 00:00 |
23:34:27.74 |
-01:56:32.8 |
HIP 116290 |
21.49 |
| 2026-09-22 12:00 |
23:34:17.68 |
-01:57:35.3 |
HIP 116290 |
19.32 |
| 2026-09-23 00:00 |
23:34:07.63 |
-01:58:37.9 |
HIP 116290 |
17.31 |
| 2026-09-23 12:00 |
23:33:57.59 |
-01:59:40.3 |
HIP 116290 |
15.52 |
| 2026-09-24 00:00 |
23:33:47.57 |
-02:00:42.7 |
HIP 116290 |
14.04 |
| 2026-09-24 12:00 |
23:33:37.56 |
-02:01:45.0 |
HIP 116290 |
12.96 |
| 2026-09-25 00:00 |
23:33:27.57 |
-02:02:47.3 |
HIP 116290 |
12.38 |
| 2026-09-25 12:00 |
23:33:17.59 |
-02:03:49.4 |
HIP 116290 |
12.38 |
| 2026-09-26 00:00 |
23:33:07.63 |
-02:04:51.5 |
HIP 116290 |
12.96 |
| 2026-09-26 12:00 |
23:32:57.69 |
-02:05:53.4 |
HIP 116290 |
14.03 |
| 2026-09-27 00:00 |
23:32:47.77 |
-02:06:55.3 |
HIP 116290 |
15.50 |
| 2026-09-27 12:00 |
23:32:37.88 |
-02:07:57.0 |
HIP 116290 |
17.26 |
| 2026-09-28 00:00 |
23:32:28.00 |
-02:08:58.6 |
HIP 116290 |
19.23 |
| 2026-09-28 12:00 |
23:32:18.15 |
-02:10:00.0 |
HIP 116290 |
21.34 |
| 2026-09-29 00:00 |
23:32:08.32 |
-02:11:01.4 |
HIP 116290 |
23.57 |
| 2026-09-29 12:00 |
23:31:58.52 |
-02:12:02.5 |
HIP 116290 |
25.86 |
| 2026-09-30 00:00 |
23:31:48.75 |
-02:13:03.6 |
HIP 116290 |
28.22 |
| 2026-09-30 12:00 |
23:31:39.00 |
-02:14:04.4 |
HIP 116290 |
30.61 |
| 2026-10-01 00:00 |
23:31:29.28 |
-02:15:05.1 |
HIP 116290 |
33.04 |
| 2026-10-01 12:00 |
23:31:19.60 |
-02:16:05.7 |
HIP 116290 |
35.48 |
| 2026-10-02 00:00 |
23:31:09.94 |
-02:17:06.0 |
HIP 116290 |
37.94 |
| 2026-10-02 12:00 |
23:31:00.31 |
-02:18:06.2 |
HIP 115945 |
38.50 |
| 2026-10-03 00:00 |
23:30:50.72 |
-02:19:06.1 |
HIP 115945 |
37.92 |
| 2026-10-03 12:00 |
23:30:41.17 |
-02:20:05.9 |
HIP 115945 |
37.52 |
| 2026-10-04 00:00 |
23:30:31.64 |
-02:21:05.5 |
HIP 115862 |
36.01 |
| 2026-10-04 12:00 |
23:30:22.16 |
-02:22:04.8 |
HIP 115862 |
33.47 |
| 2026-10-05 00:00 |
23:30:12.71 |
-02:23:03.9 |
HIP 115862 |
30.94 |
| 2026-10-05 12:00 |
23:30:03.30 |
-02:24:02.8 |
HIP 115862 |
28.43 |
| 2026-10-06 00:00 |
23:29:53.94 |
-02:25:01.5 |
HIP 115862 |
25.93 |
| 2026-10-06 12:00 |
23:29:44.61 |
-02:25:59.9 |
HIP 115862 |
23.45 |
| 2026-10-07 00:00 |
23:29:35.33 |
-02:26:58.0 |
HIP 115862 |
21.00 |
| 2026-10-07 12:00 |
23:29:26.08 |
-02:27:55.9 |
HIP 115862 |
18.57 |
| 2026-10-08 00:00 |
23:29:16.89 |
-02:28:53.6 |
HIP 115862 |
16.17 |
| 2026-10-08 12:00 |
23:29:07.74 |
-02:29:50.9 |
HIP 115862 |
13.82 |
| 2026-10-09 00:00 |
23:28:58.63 |
-02:30:48.0 |
HIP 115862 |
11.54 |
| 2026-10-09 12:00 |
23:28:49.58 |
-02:31:44.8 |
HIP 115862 |
9.35 |
| 2026-10-10 00:00 |
23:28:40.57 |
-02:32:41.3 |
HIP 115862 |
7.35 |
| 2026-10-10 12:00 |
23:28:31.61 |
-02:33:37.4 |
HIP 115862 |
5.70 |
| 2026-10-11 00:00 |
23:28:22.71 |
-02:34:33.3 |
HIP 115862 |
4.78 |