| 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) |
| 2026-09-20 00:00 |
05:06:11.26 |
+65:06:31.6 |
HIP 24017 |
25.21 |
| 2026-09-20 12:00 |
05:06:10.52 |
+65:06:49.6 |
HIP 24017 |
25.41 |
| 2026-09-21 00:00 |
05:06:09.75 |
+65:07:07.6 |
HIP 24017 |
25.62 |
| 2026-09-21 12:00 |
05:06:08.94 |
+65:07:25.5 |
HIP 24017 |
25.84 |
| 2026-09-22 00:00 |
05:06:08.09 |
+65:07:43.3 |
HIP 24017 |
26.05 |
| 2026-09-22 12:00 |
05:06:07.21 |
+65:08:01.1 |
HIP 24017 |
26.28 |
| 2026-09-23 00:00 |
05:06:06.28 |
+65:08:18.9 |
HIP 24017 |
26.51 |
| 2026-09-23 12:00 |
05:06:05.32 |
+65:08:36.6 |
HIP 24017 |
26.74 |
| 2026-09-24 00:00 |
05:06:04.32 |
+65:08:54.3 |
HIP 24017 |
26.98 |
| 2026-09-24 12:00 |
05:06:03.28 |
+65:09:11.9 |
HIP 24017 |
27.22 |
| 2026-09-25 00:00 |
05:06:02.21 |
+65:09:29.4 |
HIP 24017 |
27.47 |
| 2026-09-25 12:00 |
05:06:01.09 |
+65:09:46.9 |
HIP 24017 |
27.72 |
| 2026-09-26 00:00 |
05:05:59.94 |
+65:10:04.4 |
HIP 24017 |
27.97 |
| 2026-09-26 12:00 |
05:05:58.75 |
+65:10:21.8 |
HIP 24017 |
28.23 |
| 2026-09-27 00:00 |
05:05:57.53 |
+65:10:39.1 |
HIP 24017 |
28.50 |
| 2026-09-27 12:00 |
05:05:56.26 |
+65:10:56.4 |
HIP 24017 |
28.76 |
| 2026-09-28 00:00 |
05:05:54.96 |
+65:11:13.6 |
HIP 24017 |
29.03 |
| 2026-09-28 12:00 |
05:05:53.62 |
+65:11:30.8 |
HIP 24017 |
29.31 |
| 2026-09-29 00:00 |
05:05:52.24 |
+65:11:47.8 |
HIP 24017 |
29.59 |
| 2026-09-29 12:00 |
05:05:50.82 |
+65:12:04.9 |
HIP 24017 |
29.87 |
| 2026-09-30 00:00 |
05:05:49.37 |
+65:12:21.8 |
HIP 23455 |
30.07 |
| 2026-09-30 12:00 |
05:05:47.88 |
+65:12:38.7 |
HIP 23455 |
29.76 |
| 2026-10-01 00:00 |
05:05:46.35 |
+65:12:55.5 |
HIP 23455 |
29.45 |
| 2026-10-01 12:00 |
05:05:44.79 |
+65:13:12.3 |
HIP 23455 |
29.13 |
| 2026-10-02 00:00 |
05:05:43.19 |
+65:13:29.0 |
HIP 23455 |
28.82 |
| 2026-10-02 12:00 |
05:05:41.55 |
+65:13:45.6 |
HIP 23455 |
28.50 |
| 2026-10-03 00:00 |
05:05:39.87 |
+65:14:02.1 |
HIP 23455 |
28.18 |
| 2026-10-03 12:00 |
05:05:38.16 |
+65:14:18.6 |
HIP 23455 |
27.86 |
| 2026-10-04 00:00 |
05:05:36.41 |
+65:14:35.0 |
HIP 23455 |
27.53 |
| 2026-10-04 12:00 |
05:05:34.62 |
+65:14:51.3 |
HIP 23455 |
27.21 |
| 2026-10-05 00:00 |
05:05:32.79 |
+65:15:07.5 |
HIP 23455 |
26.88 |
| 2026-10-05 12:00 |
05:05:30.93 |
+65:15:23.6 |
HIP 23455 |
26.55 |
| 2026-10-06 00:00 |
05:05:29.04 |
+65:15:39.7 |
HIP 23455 |
26.22 |
| 2026-10-06 12:00 |
05:05:27.10 |
+65:15:55.7 |
HIP 23455 |
25.89 |
| 2026-10-07 00:00 |
05:05:25.13 |
+65:16:11.6 |
HIP 23455 |
25.56 |
| 2026-10-07 12:00 |
05:05:23.12 |
+65:16:27.4 |
HIP 23455 |
25.22 |
| 2026-10-08 00:00 |
05:05:21.08 |
+65:16:43.1 |
HIP 23455 |
24.89 |
| 2026-10-08 12:00 |
05:05:19.00 |
+65:16:58.7 |
HIP 23455 |
24.55 |
| 2026-10-09 00:00 |
05:05:16.88 |
+65:17:14.2 |
HIP 23455 |
24.21 |
| 2026-10-09 12:00 |
05:05:14.73 |
+65:17:29.7 |
HIP 23455 |
23.87 |
| 2026-10-10 00:00 |
05:05:12.54 |
+65:17:45.0 |
HIP 23455 |
23.53 |
| 2026-10-10 12:00 |
05:05:10.32 |
+65:18:00.3 |
HIP 23455 |
23.18 |
| 2026-10-11 00:00 |
05:05:08.06 |
+65:18:15.4 |
HIP 23455 |
22.84 |