| Parameter |
Value |
| Designation |
C/1988 J1 (Shoemaker-Holt) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1988-02-14T05:17:56.938560Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:36Z |
| Obs used |
84 |
| NEO |
- |
| M1 |
5.900 |
| K1 |
21.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1988-06-23.0000000 |
| e |
0.99780777 |
| q (au) |
1.174487 |
| a (au) |
535.749413 |
| i (deg) |
62.807050 |
| Ω (om, deg) |
288.765006 |
| ω (w, deg) |
326.515452 |
| M (ma, deg) |
0.010315 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.971 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.971 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.987 |
| 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) |
| 2026-07-29 00:00 |
05:04:02.68 |
+64:35:26.4 |
HIP 23622 |
27.82 |
| 2026-07-29 12:00 |
05:04:05.58 |
+64:35:41.3 |
HIP 23622 |
28.02 |
| 2026-07-30 00:00 |
05:04:08.46 |
+64:35:56.3 |
HIP 23622 |
28.23 |
| 2026-07-30 12:00 |
05:04:11.31 |
+64:36:11.4 |
HIP 23622 |
28.44 |
| 2026-07-31 00:00 |
05:04:14.13 |
+64:36:26.6 |
HIP 23622 |
28.66 |
| 2026-07-31 12:00 |
05:04:16.93 |
+64:36:41.8 |
HIP 23622 |
28.88 |
| 2026-08-01 00:00 |
05:04:19.70 |
+64:36:57.2 |
HIP 23622 |
29.11 |
| 2026-08-01 12:00 |
05:04:22.44 |
+64:37:12.6 |
HIP 23622 |
29.34 |
| 2026-08-02 00:00 |
05:04:25.16 |
+64:37:28.1 |
HIP 23622 |
29.58 |
| 2026-08-02 12:00 |
05:04:27.85 |
+64:37:43.7 |
HIP 23622 |
29.82 |
| 2026-08-03 00:00 |
05:04:30.51 |
+64:37:59.4 |
HIP 23622 |
30.07 |
| 2026-08-03 12:00 |
05:04:33.14 |
+64:38:15.2 |
HIP 23622 |
30.32 |
| 2026-08-04 00:00 |
05:04:35.74 |
+64:38:31.0 |
HIP 23622 |
30.58 |
| 2026-08-04 12:00 |
05:04:38.32 |
+64:38:46.9 |
HIP 23622 |
30.84 |
| 2026-08-05 00:00 |
05:04:40.86 |
+64:39:02.9 |
HIP 23622 |
31.10 |
| 2026-08-05 12:00 |
05:04:43.38 |
+64:39:19.0 |
HIP 23622 |
31.37 |
| 2026-08-06 00:00 |
05:04:45.87 |
+64:39:35.2 |
HIP 23622 |
31.64 |
| 2026-08-06 12:00 |
05:04:48.33 |
+64:39:51.4 |
HIP 23622 |
31.92 |
| 2026-08-07 00:00 |
05:04:50.76 |
+64:40:07.7 |
HIP 23622 |
32.20 |
| 2026-08-07 12:00 |
05:04:53.16 |
+64:40:24.1 |
HIP 23622 |
32.48 |
| 2026-08-08 00:00 |
05:04:55.53 |
+64:40:40.5 |
HIP 23622 |
32.76 |
| 2026-08-08 12:00 |
05:04:57.87 |
+64:40:57.0 |
HIP 23622 |
33.05 |
| 2026-08-09 00:00 |
05:05:00.18 |
+64:41:13.6 |
HIP 24017 |
33.33 |
| 2026-08-09 12:00 |
05:05:02.46 |
+64:41:30.3 |
HIP 24017 |
32.99 |
| 2026-08-10 00:00 |
05:05:04.71 |
+64:41:47.0 |
HIP 24017 |
32.66 |
| 2026-08-10 12:00 |
05:05:06.92 |
+64:42:03.8 |
HIP 24017 |
32.33 |
| 2026-08-11 00:00 |
05:05:09.11 |
+64:42:20.6 |
HIP 24017 |
32.00 |
| 2026-08-11 12:00 |
05:05:11.26 |
+64:42:37.6 |
HIP 24017 |
31.67 |
| 2026-08-12 00:00 |
05:05:13.39 |
+64:42:54.5 |
HIP 24017 |
31.35 |
| 2026-08-12 12:00 |
05:05:15.48 |
+64:43:11.6 |
HIP 24017 |
31.03 |
| 2026-08-13 00:00 |
05:05:17.54 |
+64:43:28.7 |
HIP 24017 |
30.72 |
| 2026-08-13 12:00 |
05:05:19.57 |
+64:43:45.8 |
HIP 24017 |
30.41 |
| 2026-08-14 00:00 |
05:05:21.56 |
+64:44:03.1 |
HIP 24017 |
30.10 |
| 2026-08-14 12:00 |
05:05:23.52 |
+64:44:20.3 |
HIP 24017 |
29.80 |
| 2026-08-15 00:00 |
05:05:25.45 |
+64:44:37.7 |
HIP 24017 |
29.50 |
| 2026-08-15 12:00 |
05:05:27.35 |
+64:44:55.1 |
HIP 24017 |
29.21 |
| 2026-08-16 00:00 |
05:05:29.22 |
+64:45:12.5 |
HIP 24017 |
28.92 |
| 2026-08-16 12:00 |
05:05:31.05 |
+64:45:30.0 |
HIP 24017 |
28.63 |
| 2026-08-17 00:00 |
05:05:32.85 |
+64:45:47.5 |
HIP 24017 |
28.35 |
| 2026-08-17 12:00 |
05:05:34.61 |
+64:46:05.1 |
HIP 24017 |
28.08 |
| 2026-08-18 00:00 |
05:05:36.34 |
+64:46:22.8 |
HIP 24017 |
27.81 |
| 2026-08-18 12:00 |
05:05:38.04 |
+64:46:40.5 |
HIP 24017 |
27.54 |
| 2026-08-19 00:00 |
05:05:39.70 |
+64:46:58.2 |
HIP 24017 |
27.28 |