| Parameter |
Value |
| Designation |
C/1988 B1 (Shoemaker) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1987-03-20T04:30:14.852160Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:36Z |
| Obs used |
63 |
| NEO |
- |
| M1 |
5.600 |
| K1 |
10.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1988-07-24.0000000 |
| e |
1.00306479 |
| q (au) |
5.030939 |
| a (au) |
-1641.528202 |
| i (deg) |
80.568294 |
| Ω (om, deg) |
325.168069 |
| ω (w, deg) |
124.223736 |
| M (ma, deg) |
0.007288 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.483 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.483 |
| n |
2.000 |
| gf |
0.998 |
| gb |
-0.500 |
| 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 |
07:00:57.93 |
-73:19:19.6 |
HIP 33813 |
13.86 |
| 2026-05-12 12:00 |
07:01:01.72 |
-73:18:57.2 |
HIP 33813 |
14.21 |
| 2026-05-13 00:00 |
07:01:05.54 |
-73:18:35.0 |
HIP 33795 |
14.54 |
| 2026-05-13 12:00 |
07:01:09.41 |
-73:18:12.9 |
HIP 33795 |
14.18 |
| 2026-05-14 00:00 |
07:01:13.33 |
-73:17:50.9 |
HIP 33795 |
13.83 |
| 2026-05-14 12:00 |
07:01:17.28 |
-73:17:29.2 |
HIP 33795 |
13.49 |
| 2026-05-15 00:00 |
07:01:21.27 |
-73:17:07.5 |
HIP 33795 |
13.15 |
| 2026-05-15 12:00 |
07:01:25.31 |
-73:16:46.1 |
HIP 33795 |
12.83 |
| 2026-05-16 00:00 |
07:01:29.39 |
-73:16:24.7 |
HIP 33795 |
12.52 |
| 2026-05-16 12:00 |
07:01:33.51 |
-73:16:03.6 |
HIP 33795 |
12.22 |
| 2026-05-17 00:00 |
07:01:37.67 |
-73:15:42.5 |
HIP 33795 |
11.94 |
| 2026-05-17 12:00 |
07:01:41.87 |
-73:15:21.7 |
HIP 33795 |
11.67 |
| 2026-05-18 00:00 |
07:01:46.11 |
-73:15:01.0 |
HIP 33795 |
11.42 |
| 2026-05-18 12:00 |
07:01:50.38 |
-73:14:40.5 |
HIP 33795 |
11.18 |
| 2026-05-19 00:00 |
07:01:54.70 |
-73:14:20.1 |
HIP 33795 |
10.96 |
| 2026-05-19 12:00 |
07:01:59.06 |
-73:13:59.9 |
HIP 33795 |
10.76 |
| 2026-05-20 00:00 |
07:02:03.45 |
-73:13:39.8 |
HIP 33795 |
10.58 |
| 2026-05-20 12:00 |
07:02:07.88 |
-73:13:20.0 |
HIP 33795 |
10.42 |
| 2026-05-21 00:00 |
07:02:12.35 |
-73:13:00.3 |
HIP 33795 |
10.29 |
| 2026-05-21 12:00 |
07:02:16.85 |
-73:12:40.7 |
HIP 33795 |
10.17 |
| 2026-05-22 00:00 |
07:02:21.40 |
-73:12:21.4 |
HIP 33795 |
10.09 |
| 2026-05-22 12:00 |
07:02:25.97 |
-73:12:02.2 |
HIP 33795 |
10.02 |
| 2026-05-23 00:00 |
07:02:30.59 |
-73:11:43.2 |
HIP 33795 |
9.98 |
| 2026-05-23 12:00 |
07:02:35.24 |
-73:11:24.3 |
HIP 33795 |
9.96 |
| 2026-05-24 00:00 |
07:02:39.92 |
-73:11:05.6 |
HIP 33795 |
9.98 |
| 2026-05-24 12:00 |
07:02:44.64 |
-73:10:47.1 |
HIP 33795 |
10.01 |
| 2026-05-25 00:00 |
07:02:49.39 |
-73:10:28.8 |
HIP 33795 |
10.07 |
| 2026-05-25 12:00 |
07:02:54.18 |
-73:10:10.7 |
HIP 33795 |
10.16 |
| 2026-05-26 00:00 |
07:02:59.00 |
-73:09:52.7 |
HIP 33795 |
10.26 |
| 2026-05-26 12:00 |
07:03:03.85 |
-73:09:35.0 |
HIP 33795 |
10.40 |
| 2026-05-27 00:00 |
07:03:08.74 |
-73:09:17.4 |
HIP 33795 |
10.55 |
| 2026-05-27 12:00 |
07:03:13.65 |
-73:09:00.0 |
HIP 33795 |
10.73 |
| 2026-05-28 00:00 |
07:03:18.60 |
-73:08:42.7 |
HIP 33795 |
10.92 |
| 2026-05-28 12:00 |
07:03:23.59 |
-73:08:25.7 |
HIP 33795 |
11.14 |
| 2026-05-29 00:00 |
07:03:28.60 |
-73:08:08.8 |
HIP 33795 |
11.37 |
| 2026-05-29 12:00 |
07:03:33.64 |
-73:07:52.2 |
HIP 33795 |
11.62 |
| 2026-05-30 00:00 |
07:03:38.72 |
-73:07:35.7 |
HIP 33795 |
11.88 |
| 2026-05-30 12:00 |
07:03:43.82 |
-73:07:19.4 |
HIP 33795 |
12.16 |
| 2026-05-31 00:00 |
07:03:48.96 |
-73:07:03.3 |
HIP 33795 |
12.46 |
| 2026-05-31 12:00 |
07:03:54.12 |
-73:06:47.3 |
HIP 33795 |
12.76 |
| 2026-06-01 00:00 |
07:03:59.32 |
-73:06:31.6 |
HIP 33795 |
13.08 |
| 2026-06-01 12:00 |
07:04:04.54 |
-73:06:16.1 |
HIP 33795 |
13.41 |
| 2026-06-02 00:00 |
07:04:09.79 |
-73:06:00.8 |
HIP 33795 |
13.75 |