| Parameter |
Value |
| Designation |
C/1977 R1 (Kohler) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1977-11-10T13:40:46.989120Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:27Z |
| Obs used |
421 |
| NEO |
- |
| M1 |
7.300 |
| K1 |
13.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1977-11-01.0000000 |
| e |
0.99954935 |
| q (au) |
0.990576 |
| a (au) |
2198.096723 |
| i (deg) |
48.711865 |
| Ω (om, deg) |
182.522684 |
| ω (w, deg) |
163.486616 |
| M (ma, deg) |
359.999908 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.933 + 5.854\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.933 |
| n |
5.854 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
0.800 |
| δ90 |
1.000 |
| 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 |
10:16:43.36 |
-12:42:24.1 |
HIP 50344 |
23.58 |
| 2026-06-01 12:00 |
10:16:43.60 |
-12:42:15.6 |
HIP 50344 |
23.72 |
| 2026-06-02 00:00 |
10:16:43.85 |
-12:42:07.2 |
HIP 50344 |
23.86 |
| 2026-06-02 12:00 |
10:16:44.12 |
-12:41:58.8 |
HIP 50344 |
24.00 |
| 2026-06-03 00:00 |
10:16:44.39 |
-12:41:50.6 |
HIP 50344 |
24.13 |
| 2026-06-03 12:00 |
10:16:44.68 |
-12:41:42.4 |
HIP 50344 |
24.27 |
| 2026-06-04 00:00 |
10:16:44.98 |
-12:41:34.3 |
HIP 50344 |
24.40 |
| 2026-06-04 12:00 |
10:16:45.29 |
-12:41:26.2 |
HIP 50344 |
24.54 |
| 2026-06-05 00:00 |
10:16:45.62 |
-12:41:18.3 |
HIP 50344 |
24.67 |
| 2026-06-05 12:00 |
10:16:45.96 |
-12:41:10.4 |
HIP 50344 |
24.80 |
| 2026-06-06 00:00 |
10:16:46.31 |
-12:41:02.6 |
HIP 50344 |
24.93 |
| 2026-06-06 12:00 |
10:16:46.67 |
-12:40:54.9 |
HIP 50344 |
25.05 |
| 2026-06-07 00:00 |
10:16:47.05 |
-12:40:47.3 |
HIP 50344 |
25.18 |
| 2026-06-07 12:00 |
10:16:47.44 |
-12:40:39.8 |
HIP 50344 |
25.31 |
| 2026-06-08 00:00 |
10:16:47.84 |
-12:40:32.4 |
HIP 50344 |
25.43 |
| 2026-06-08 12:00 |
10:16:48.25 |
-12:40:25.0 |
HIP 50344 |
25.55 |
| 2026-06-09 00:00 |
10:16:48.68 |
-12:40:17.7 |
HIP 50344 |
25.68 |
| 2026-06-09 12:00 |
10:16:49.12 |
-12:40:10.5 |
HIP 50344 |
25.80 |
| 2026-06-10 00:00 |
10:16:49.57 |
-12:40:03.5 |
HIP 50344 |
25.92 |
| 2026-06-10 12:00 |
10:16:50.03 |
-12:39:56.4 |
HIP 50344 |
26.04 |
| 2026-06-11 00:00 |
10:16:50.50 |
-12:39:49.5 |
HIP 50344 |
26.16 |
| 2026-06-11 12:00 |
10:16:50.99 |
-12:39:42.7 |
HIP 50344 |
26.28 |
| 2026-06-12 00:00 |
10:16:51.49 |
-12:39:36.0 |
HIP 50344 |
26.39 |
| 2026-06-12 12:00 |
10:16:52.00 |
-12:39:29.3 |
HIP 50344 |
26.51 |
| 2026-06-13 00:00 |
10:16:52.53 |
-12:39:22.8 |
HIP 50344 |
26.63 |
| 2026-06-13 12:00 |
10:16:53.06 |
-12:39:16.3 |
HIP 50344 |
26.74 |
| 2026-06-14 00:00 |
10:16:53.61 |
-12:39:09.9 |
HIP 50344 |
26.85 |
| 2026-06-14 12:00 |
10:16:54.17 |
-12:39:03.6 |
HIP 50344 |
26.97 |
| 2026-06-15 00:00 |
10:16:54.74 |
-12:38:57.4 |
HIP 50344 |
27.08 |
| 2026-06-15 12:00 |
10:16:55.32 |
-12:38:51.3 |
HIP 50344 |
27.19 |
| 2026-06-16 00:00 |
10:16:55.92 |
-12:38:45.3 |
HIP 50344 |
27.30 |
| 2026-06-16 12:00 |
10:16:56.53 |
-12:38:39.4 |
HIP 50344 |
27.41 |
| 2026-06-17 00:00 |
10:16:57.14 |
-12:38:33.6 |
HIP 50344 |
27.52 |
| 2026-06-17 12:00 |
10:16:57.78 |
-12:38:27.9 |
HIP 50344 |
27.63 |
| 2026-06-18 00:00 |
10:16:58.42 |
-12:38:22.3 |
HIP 50344 |
27.74 |
| 2026-06-18 12:00 |
10:16:59.07 |
-12:38:16.7 |
HIP 50344 |
27.85 |
| 2026-06-19 00:00 |
10:16:59.74 |
-12:38:11.3 |
HIP 50344 |
27.96 |
| 2026-06-19 12:00 |
10:17:00.41 |
-12:38:05.9 |
HIP 50344 |
28.07 |
| 2026-06-20 00:00 |
10:17:01.10 |
-12:38:00.7 |
HIP 50344 |
28.17 |
| 2026-06-20 12:00 |
10:17:01.80 |
-12:37:55.5 |
HIP 50344 |
28.28 |
| 2026-06-21 00:00 |
10:17:02.51 |
-12:37:50.5 |
HIP 50344 |
28.39 |
| 2026-06-21 12:00 |
10:17:03.23 |
-12:37:45.5 |
HIP 50344 |
28.49 |
| 2026-06-22 00:00 |
10:17:03.97 |
-12:37:40.7 |
HIP 50344 |
28.60 |