| 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) |
| 2026-06-01 00:00 |
04:56:28.53 |
+64:19:55.6 |
HIP 22961 |
4.25 |
| 2026-06-01 12:00 |
04:56:32.87 |
+64:19:55.7 |
HIP 22961 |
4.31 |
| 2026-06-02 00:00 |
04:56:37.22 |
+64:19:55.9 |
HIP 22961 |
4.41 |
| 2026-06-02 12:00 |
04:56:41.57 |
+64:19:56.2 |
HIP 22961 |
4.56 |
| 2026-06-03 00:00 |
04:56:45.92 |
+64:19:56.7 |
HIP 22961 |
4.74 |
| 2026-06-03 12:00 |
04:56:50.27 |
+64:19:57.4 |
HIP 22961 |
4.96 |
| 2026-06-04 00:00 |
04:56:54.62 |
+64:19:58.2 |
HIP 22961 |
5.22 |
| 2026-06-04 12:00 |
04:56:58.98 |
+64:19:59.1 |
HIP 22961 |
5.50 |
| 2026-06-05 00:00 |
04:57:03.33 |
+64:20:00.3 |
HIP 22961 |
5.80 |
| 2026-06-05 12:00 |
04:57:07.69 |
+64:20:01.5 |
HIP 22961 |
6.12 |
| 2026-06-06 00:00 |
04:57:12.05 |
+64:20:02.9 |
HIP 22961 |
6.46 |
| 2026-06-06 12:00 |
04:57:16.41 |
+64:20:04.5 |
HIP 22961 |
6.82 |
| 2026-06-07 00:00 |
04:57:20.76 |
+64:20:06.2 |
HIP 22961 |
7.18 |
| 2026-06-07 12:00 |
04:57:25.12 |
+64:20:08.0 |
HIP 22961 |
7.56 |
| 2026-06-08 00:00 |
04:57:29.48 |
+64:20:10.0 |
HIP 22961 |
7.95 |
| 2026-06-08 12:00 |
04:57:33.84 |
+64:20:12.2 |
HIP 22961 |
8.34 |
| 2026-06-09 00:00 |
04:57:38.19 |
+64:20:14.5 |
HIP 22961 |
8.74 |
| 2026-06-09 12:00 |
04:57:42.55 |
+64:20:16.9 |
HIP 22961 |
9.15 |
| 2026-06-10 00:00 |
04:57:46.90 |
+64:20:19.5 |
HIP 22961 |
9.56 |
| 2026-06-10 12:00 |
04:57:51.25 |
+64:20:22.3 |
HIP 22961 |
9.97 |
| 2026-06-11 00:00 |
04:57:55.60 |
+64:20:25.1 |
HIP 22961 |
10.39 |
| 2026-06-11 12:00 |
04:57:59.95 |
+64:20:28.2 |
HIP 22961 |
10.81 |
| 2026-06-12 00:00 |
04:58:04.29 |
+64:20:31.4 |
HIP 22961 |
11.24 |
| 2026-06-12 12:00 |
04:58:08.63 |
+64:20:34.7 |
HIP 22961 |
11.66 |
| 2026-06-13 00:00 |
04:58:12.97 |
+64:20:38.2 |
HIP 22961 |
12.09 |
| 2026-06-13 12:00 |
04:58:17.31 |
+64:20:41.8 |
HIP 22961 |
12.53 |
| 2026-06-14 00:00 |
04:58:21.64 |
+64:20:45.6 |
HIP 22961 |
12.96 |
| 2026-06-14 12:00 |
04:58:25.96 |
+64:20:49.5 |
HIP 22961 |
13.39 |
| 2026-06-15 00:00 |
04:58:30.29 |
+64:20:53.6 |
HIP 22961 |
13.83 |
| 2026-06-15 12:00 |
04:58:34.60 |
+64:20:57.8 |
HIP 22961 |
14.27 |
| 2026-06-16 00:00 |
04:58:38.92 |
+64:21:02.2 |
HIP 22961 |
14.71 |
| 2026-06-16 12:00 |
04:58:43.22 |
+64:21:06.7 |
HIP 22961 |
15.15 |
| 2026-06-17 00:00 |
04:58:47.53 |
+64:21:11.3 |
HIP 22961 |
15.59 |
| 2026-06-17 12:00 |
04:58:51.82 |
+64:21:16.1 |
HIP 22961 |
16.03 |
| 2026-06-18 00:00 |
04:58:56.11 |
+64:21:21.1 |
HIP 22961 |
16.47 |
| 2026-06-18 12:00 |
04:59:00.40 |
+64:21:26.2 |
HIP 22961 |
16.91 |
| 2026-06-19 00:00 |
04:59:04.67 |
+64:21:31.4 |
HIP 22961 |
17.35 |
| 2026-06-19 12:00 |
04:59:08.94 |
+64:21:36.8 |
HIP 22961 |
17.80 |
| 2026-06-20 00:00 |
04:59:13.20 |
+64:21:42.3 |
HIP 22961 |
18.24 |
| 2026-06-20 12:00 |
04:59:17.46 |
+64:21:47.9 |
HIP 22961 |
18.68 |
| 2026-06-21 00:00 |
04:59:21.71 |
+64:21:53.7 |
HIP 22961 |
19.13 |
| 2026-06-21 12:00 |
04:59:25.94 |
+64:21:59.7 |
HIP 22961 |
19.57 |
| 2026-06-22 00:00 |
04:59:30.17 |
+64:22:05.7 |
HIP 22961 |
20.01 |