| Parameter |
Value |
| Designation |
C/1987 W3 (Jensen-Shoemaker) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1988-01-18T16:22:02.138880Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:36Z |
| Obs used |
33 |
| NEO |
- |
| M1 |
9.200 |
| K1 |
10.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1988-07-04.0000000 |
| e |
1.00360306 |
| q (au) |
3.332745 |
| a (au) |
-924.976804 |
| i (deg) |
76.700407 |
| Ω (om, deg) |
198.337713 |
| ω (w, deg) |
194.713159 |
| M (ma, deg) |
0.005862 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.127 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.127 |
| 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) |
| 2026-05-12 00:00 |
12:34:38.42 |
-17:15:29.7 |
HIP 61325 |
14.96 |
| 2026-05-12 12:00 |
12:34:37.06 |
-17:15:15.8 |
HIP 61325 |
14.57 |
| 2026-05-13 00:00 |
12:34:35.71 |
-17:15:02.0 |
HIP 61325 |
14.18 |
| 2026-05-13 12:00 |
12:34:34.37 |
-17:14:48.1 |
HIP 61325 |
13.80 |
| 2026-05-14 00:00 |
12:34:33.05 |
-17:14:34.3 |
HIP 61325 |
13.41 |
| 2026-05-14 12:00 |
12:34:31.73 |
-17:14:20.5 |
HIP 61325 |
13.03 |
| 2026-05-15 00:00 |
12:34:30.43 |
-17:14:06.7 |
HIP 61325 |
12.65 |
| 2026-05-15 12:00 |
12:34:29.14 |
-17:13:52.9 |
HIP 61325 |
12.27 |
| 2026-05-16 00:00 |
12:34:27.86 |
-17:13:39.2 |
HIP 61325 |
11.90 |
| 2026-05-16 12:00 |
12:34:26.59 |
-17:13:25.5 |
HIP 61325 |
11.53 |
| 2026-05-17 00:00 |
12:34:25.33 |
-17:13:11.8 |
HIP 61325 |
11.16 |
| 2026-05-17 12:00 |
12:34:24.09 |
-17:12:58.2 |
HIP 61325 |
10.80 |
| 2026-05-18 00:00 |
12:34:22.86 |
-17:12:44.6 |
HIP 61325 |
10.43 |
| 2026-05-18 12:00 |
12:34:21.64 |
-17:12:31.0 |
HIP 61325 |
10.07 |
| 2026-05-19 00:00 |
12:34:20.43 |
-17:12:17.5 |
HIP 61325 |
9.72 |
| 2026-05-19 12:00 |
12:34:19.23 |
-17:12:04.0 |
HIP 61325 |
9.36 |
| 2026-05-20 00:00 |
12:34:18.05 |
-17:11:50.5 |
HIP 61325 |
9.01 |
| 2026-05-20 12:00 |
12:34:16.88 |
-17:11:37.1 |
HIP 61325 |
8.67 |
| 2026-05-21 00:00 |
12:34:15.72 |
-17:11:23.7 |
HIP 61325 |
8.32 |
| 2026-05-21 12:00 |
12:34:14.57 |
-17:11:10.4 |
HIP 61325 |
7.98 |
| 2026-05-22 00:00 |
12:34:13.44 |
-17:10:57.1 |
HIP 61325 |
7.64 |
| 2026-05-22 12:00 |
12:34:12.32 |
-17:10:43.8 |
HIP 61325 |
7.31 |
| 2026-05-23 00:00 |
12:34:11.21 |
-17:10:30.6 |
HIP 61325 |
6.98 |
| 2026-05-23 12:00 |
12:34:10.12 |
-17:10:17.4 |
HIP 61325 |
6.65 |
| 2026-05-24 00:00 |
12:34:09.04 |
-17:10:04.3 |
HIP 61325 |
6.33 |
| 2026-05-24 12:00 |
12:34:07.97 |
-17:09:51.2 |
HIP 61325 |
6.01 |
| 2026-05-25 00:00 |
12:34:06.91 |
-17:09:38.1 |
HIP 61325 |
5.69 |
| 2026-05-25 12:00 |
12:34:05.87 |
-17:09:25.1 |
HIP 61325 |
5.38 |
| 2026-05-26 00:00 |
12:34:04.84 |
-17:09:12.2 |
HIP 61325 |
5.08 |
| 2026-05-26 12:00 |
12:34:03.83 |
-17:08:59.3 |
HIP 61325 |
4.78 |
| 2026-05-27 00:00 |
12:34:02.82 |
-17:08:46.4 |
HIP 61325 |
4.48 |
| 2026-05-27 12:00 |
12:34:01.83 |
-17:08:33.6 |
HIP 61325 |
4.19 |
| 2026-05-28 00:00 |
12:34:00.86 |
-17:08:20.9 |
HIP 61325 |
3.91 |
| 2026-05-28 12:00 |
12:33:59.90 |
-17:08:08.1 |
HIP 61325 |
3.63 |
| 2026-05-29 00:00 |
12:33:58.95 |
-17:07:55.5 |
HIP 61325 |
3.36 |
| 2026-05-29 12:00 |
12:33:58.01 |
-17:07:42.9 |
HIP 61325 |
3.10 |
| 2026-05-30 00:00 |
12:33:57.09 |
-17:07:30.3 |
HIP 61325 |
2.85 |
| 2026-05-30 12:00 |
12:33:56.19 |
-17:07:17.9 |
HIP 61325 |
2.62 |
| 2026-05-31 00:00 |
12:33:55.29 |
-17:07:05.4 |
HIP 61325 |
2.40 |
| 2026-05-31 12:00 |
12:33:54.41 |
-17:06:53.0 |
HIP 61325 |
2.20 |
| 2026-06-01 00:00 |
12:33:53.55 |
-17:06:40.7 |
HIP 61325 |
2.02 |
| 2026-06-01 12:00 |
12:33:52.70 |
-17:06:28.4 |
HIP 61325 |
1.87 |
| 2026-06-02 00:00 |
12:33:51.86 |
-17:06:16.2 |
HIP 61325 |
1.75 |