| 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) |
| 2026-05-12 00:00 |
10:16:44.45 |
-12:49:03.5 |
HIP 50344 |
16.92 |
| 2026-05-12 12:00 |
10:16:44.17 |
-12:48:52.2 |
HIP 50344 |
17.11 |
| 2026-05-13 00:00 |
10:16:43.90 |
-12:48:41.1 |
HIP 50344 |
17.30 |
| 2026-05-13 12:00 |
10:16:43.65 |
-12:48:30.0 |
HIP 50344 |
17.49 |
| 2026-05-14 00:00 |
10:16:43.40 |
-12:48:18.9 |
HIP 50344 |
17.67 |
| 2026-05-14 12:00 |
10:16:43.18 |
-12:48:07.9 |
HIP 50344 |
17.86 |
| 2026-05-15 00:00 |
10:16:42.96 |
-12:47:57.0 |
HIP 50344 |
18.04 |
| 2026-05-15 12:00 |
10:16:42.76 |
-12:47:46.1 |
HIP 50344 |
18.23 |
| 2026-05-16 00:00 |
10:16:42.56 |
-12:47:35.3 |
HIP 50344 |
18.41 |
| 2026-05-16 12:00 |
10:16:42.39 |
-12:47:24.5 |
HIP 50344 |
18.59 |
| 2026-05-17 00:00 |
10:16:42.22 |
-12:47:13.8 |
HIP 50344 |
18.77 |
| 2026-05-17 12:00 |
10:16:42.07 |
-12:47:03.2 |
HIP 50344 |
18.95 |
| 2026-05-18 00:00 |
10:16:41.93 |
-12:46:52.6 |
HIP 50344 |
19.13 |
| 2026-05-18 12:00 |
10:16:41.81 |
-12:46:42.1 |
HIP 50344 |
19.31 |
| 2026-05-19 00:00 |
10:16:41.70 |
-12:46:31.7 |
HIP 50344 |
19.48 |
| 2026-05-19 12:00 |
10:16:41.60 |
-12:46:21.3 |
HIP 50344 |
19.66 |
| 2026-05-20 00:00 |
10:16:41.51 |
-12:46:10.9 |
HIP 50344 |
19.83 |
| 2026-05-20 12:00 |
10:16:41.44 |
-12:46:00.7 |
HIP 50344 |
20.00 |
| 2026-05-21 00:00 |
10:16:41.38 |
-12:45:50.5 |
HIP 50344 |
20.17 |
| 2026-05-21 12:00 |
10:16:41.34 |
-12:45:40.4 |
HIP 50344 |
20.34 |
| 2026-05-22 00:00 |
10:16:41.30 |
-12:45:30.3 |
HIP 50344 |
20.51 |
| 2026-05-22 12:00 |
10:16:41.28 |
-12:45:20.3 |
HIP 50344 |
20.68 |
| 2026-05-23 00:00 |
10:16:41.28 |
-12:45:10.4 |
HIP 50344 |
20.84 |
| 2026-05-23 12:00 |
10:16:41.28 |
-12:45:00.5 |
HIP 50344 |
21.00 |
| 2026-05-24 00:00 |
10:16:41.30 |
-12:44:50.8 |
HIP 50344 |
21.17 |
| 2026-05-24 12:00 |
10:16:41.33 |
-12:44:41.0 |
HIP 50344 |
21.33 |
| 2026-05-25 00:00 |
10:16:41.38 |
-12:44:31.4 |
HIP 50344 |
21.49 |
| 2026-05-25 12:00 |
10:16:41.44 |
-12:44:21.8 |
HIP 50344 |
21.65 |
| 2026-05-26 00:00 |
10:16:41.51 |
-12:44:12.3 |
HIP 50344 |
21.80 |
| 2026-05-26 12:00 |
10:16:41.59 |
-12:44:02.9 |
HIP 50344 |
21.96 |
| 2026-05-27 00:00 |
10:16:41.69 |
-12:43:53.5 |
HIP 50344 |
22.11 |
| 2026-05-27 12:00 |
10:16:41.80 |
-12:43:44.3 |
HIP 50344 |
22.27 |
| 2026-05-28 00:00 |
10:16:41.92 |
-12:43:35.1 |
HIP 50344 |
22.42 |
| 2026-05-28 12:00 |
10:16:42.06 |
-12:43:25.9 |
HIP 50344 |
22.57 |
| 2026-05-29 00:00 |
10:16:42.21 |
-12:43:16.9 |
HIP 50344 |
22.72 |
| 2026-05-29 12:00 |
10:16:42.37 |
-12:43:07.9 |
HIP 50344 |
22.86 |
| 2026-05-30 00:00 |
10:16:42.54 |
-12:42:59.0 |
HIP 50344 |
23.01 |
| 2026-05-30 12:00 |
10:16:42.73 |
-12:42:50.2 |
HIP 50344 |
23.16 |
| 2026-05-31 00:00 |
10:16:42.93 |
-12:42:41.4 |
HIP 50344 |
23.30 |
| 2026-05-31 12:00 |
10:16:43.14 |
-12:42:32.7 |
HIP 50344 |
23.44 |
| 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 |