| Parameter |
Value |
| Designation |
C/1996 R1 (Hergenrother-Spahr) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1996-08-28T17:45:00.472320Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:49Z |
| Obs used |
321 |
| NEO |
- |
| M1 |
6.300 |
| K1 |
24.250 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1996-09-28.0000000 |
| e |
0.98558370 |
| q (au) |
1.899198 |
| a (au) |
131.739702 |
| i (deg) |
145.814443 |
| Ω (om, deg) |
149.745053 |
| ω (w, deg) |
139.456909 |
| M (ma, deg) |
0.019724 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.178 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.178 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.991 |
| δ90 |
9.999 |
| 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 |
12:39:37.30 |
-36:54:49.4 |
HIP 61683 |
15.66 |
| 2026-06-01 12:00 |
12:39:35.83 |
-36:54:25.9 |
HIP 61683 |
15.17 |
| 2026-06-02 00:00 |
12:39:34.38 |
-36:54:02.5 |
HIP 61683 |
14.69 |
| 2026-06-02 12:00 |
12:39:32.95 |
-36:53:39.0 |
HIP 61683 |
14.22 |
| 2026-06-03 00:00 |
12:39:31.54 |
-36:53:15.6 |
HIP 61683 |
13.74 |
| 2026-06-03 12:00 |
12:39:30.15 |
-36:52:52.2 |
HIP 61683 |
13.27 |
| 2026-06-04 00:00 |
12:39:28.78 |
-36:52:28.8 |
HIP 61683 |
12.81 |
| 2026-06-04 12:00 |
12:39:27.43 |
-36:52:05.4 |
HIP 61683 |
12.35 |
| 2026-06-05 00:00 |
12:39:26.11 |
-36:51:42.0 |
HIP 61683 |
11.89 |
| 2026-06-05 12:00 |
12:39:24.80 |
-36:51:18.7 |
HIP 61683 |
11.44 |
| 2026-06-06 00:00 |
12:39:23.52 |
-36:50:55.4 |
HIP 61683 |
10.99 |
| 2026-06-06 12:00 |
12:39:22.26 |
-36:50:32.1 |
HIP 61683 |
10.55 |
| 2026-06-07 00:00 |
12:39:21.02 |
-36:50:08.8 |
HIP 61683 |
10.11 |
| 2026-06-07 12:00 |
12:39:19.80 |
-36:49:45.6 |
HIP 61683 |
9.68 |
| 2026-06-08 00:00 |
12:39:18.60 |
-36:49:22.4 |
HIP 61683 |
9.26 |
| 2026-06-08 12:00 |
12:39:17.42 |
-36:48:59.2 |
HIP 61683 |
8.84 |
| 2026-06-09 00:00 |
12:39:16.27 |
-36:48:36.0 |
HIP 61683 |
8.43 |
| 2026-06-09 12:00 |
12:39:15.13 |
-36:48:12.9 |
HIP 61683 |
8.02 |
| 2026-06-10 00:00 |
12:39:14.02 |
-36:47:49.8 |
HIP 61683 |
7.63 |
| 2026-06-10 12:00 |
12:39:12.93 |
-36:47:26.8 |
HIP 61683 |
7.25 |
| 2026-06-11 00:00 |
12:39:11.86 |
-36:47:03.8 |
HIP 61683 |
6.87 |
| 2026-06-11 12:00 |
12:39:10.82 |
-36:46:40.8 |
HIP 61683 |
6.51 |
| 2026-06-12 00:00 |
12:39:09.79 |
-36:46:17.9 |
HIP 61683 |
6.17 |
| 2026-06-12 12:00 |
12:39:08.79 |
-36:45:55.0 |
HIP 61683 |
5.84 |
| 2026-06-13 00:00 |
12:39:07.81 |
-36:45:32.2 |
HIP 61683 |
5.53 |
| 2026-06-13 12:00 |
12:39:06.85 |
-36:45:09.4 |
HIP 61683 |
5.24 |
| 2026-06-14 00:00 |
12:39:05.92 |
-36:44:46.7 |
HIP 61683 |
4.97 |
| 2026-06-14 12:00 |
12:39:05.01 |
-36:44:24.0 |
HIP 61683 |
4.73 |
| 2026-06-15 00:00 |
12:39:04.12 |
-36:44:01.3 |
HIP 61683 |
4.52 |
| 2026-06-15 12:00 |
12:39:03.25 |
-36:43:38.8 |
HIP 61683 |
4.35 |
| 2026-06-16 00:00 |
12:39:02.40 |
-36:43:16.2 |
HIP 61683 |
4.22 |
| 2026-06-16 12:00 |
12:39:01.58 |
-36:42:53.8 |
HIP 61683 |
4.12 |
| 2026-06-17 00:00 |
12:39:00.78 |
-36:42:31.4 |
HIP 61683 |
4.07 |
| 2026-06-17 12:00 |
12:39:00.00 |
-36:42:09.0 |
HIP 61683 |
4.06 |
| 2026-06-18 00:00 |
12:38:59.25 |
-36:41:46.7 |
HIP 61683 |
4.10 |
| 2026-06-18 12:00 |
12:38:58.51 |
-36:41:24.5 |
HIP 61683 |
4.18 |
| 2026-06-19 00:00 |
12:38:57.80 |
-36:41:02.4 |
HIP 61683 |
4.29 |
| 2026-06-19 12:00 |
12:38:57.12 |
-36:40:40.3 |
HIP 61683 |
4.44 |
| 2026-06-20 00:00 |
12:38:56.45 |
-36:40:18.3 |
HIP 61683 |
4.63 |
| 2026-06-20 12:00 |
12:38:55.81 |
-36:39:56.3 |
HIP 61683 |
4.83 |
| 2026-06-21 00:00 |
12:38:55.19 |
-36:39:34.5 |
HIP 61683 |
5.06 |
| 2026-06-21 12:00 |
12:38:54.59 |
-36:39:12.7 |
HIP 61683 |
5.31 |
| 2026-06-22 00:00 |
12:38:54.02 |
-36:38:51.0 |
HIP 61683 |
5.58 |