| Parameter |
Value |
| Designation |
C/2020 R6 (Rankin) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-09-09T23:50:03.036480Z |
| Orbit solution date (soln_date, UTC) |
2021-12-17T03:12:50Z |
| Obs used |
56 |
| NEO |
- |
| M1 |
14.800 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2020-09-15T10:08:55.968000Z |
| Discovery magnitude (MPC) |
20.20 G |
| Discovery observatory (MPC) |
G96 · University of Arizona Mt. Lemmon Survey |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2020-08-21.0000000 |
| e |
0.99221066 |
| q (au) |
3.129707 |
| a (au) |
401.793824 |
| i (deg) |
82.814904 |
| Ω (om, deg) |
12.177097 |
| ω (w, deg) |
272.005055 |
| M (ma, deg) |
0.042343 |
Magnitude
Scatter + Global Linear
$$
M_a = (17.617 + 2.630\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
17.617 |
| n |
2.630 |
| gf |
1.000 |
| gb |
-0.821 |
| k |
0.800 |
| δ90 |
9.998 |
| 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) |
| 2026-07-29 00:00 |
23:57:45.69 |
+47:36:42.6 |
HIP 117956 |
27.11 |
| 2026-07-29 12:00 |
23:57:39.61 |
+47:37:38.6 |
HIP 117925 |
26.34 |
| 2026-07-30 00:00 |
23:57:33.46 |
+47:38:34.0 |
HIP 117925 |
25.13 |
| 2026-07-30 12:00 |
23:57:27.25 |
+47:39:28.8 |
HIP 117925 |
23.92 |
| 2026-07-31 00:00 |
23:57:20.96 |
+47:40:23.1 |
HIP 117925 |
22.73 |
| 2026-07-31 12:00 |
23:57:14.61 |
+47:41:16.8 |
HIP 117925 |
21.55 |
| 2026-08-01 00:00 |
23:57:08.20 |
+47:42:10.0 |
HIP 117925 |
20.39 |
| 2026-08-01 12:00 |
23:57:01.72 |
+47:43:02.6 |
HIP 117925 |
19.25 |
| 2026-08-02 00:00 |
23:56:55.17 |
+47:43:54.6 |
HIP 117925 |
18.14 |
| 2026-08-02 12:00 |
23:56:48.56 |
+47:44:46.0 |
HIP 117925 |
17.05 |
| 2026-08-03 00:00 |
23:56:41.88 |
+47:45:36.8 |
HIP 117925 |
16.01 |
| 2026-08-03 12:00 |
23:56:35.14 |
+47:46:27.0 |
HIP 117925 |
15.01 |
| 2026-08-04 00:00 |
23:56:28.33 |
+47:47:16.7 |
HIP 117925 |
14.07 |
| 2026-08-04 12:00 |
23:56:21.46 |
+47:48:05.7 |
HIP 117925 |
13.21 |
| 2026-08-05 00:00 |
23:56:14.53 |
+47:48:54.2 |
HIP 117925 |
12.43 |
| 2026-08-05 12:00 |
23:56:07.53 |
+47:49:42.0 |
HIP 117925 |
11.75 |
| 2026-08-06 00:00 |
23:56:00.47 |
+47:50:29.2 |
HIP 117925 |
11.21 |
| 2026-08-06 12:00 |
23:55:53.35 |
+47:51:15.8 |
HIP 117925 |
10.81 |
| 2026-08-07 00:00 |
23:55:46.17 |
+47:52:01.8 |
HIP 117925 |
10.57 |
| 2026-08-07 12:00 |
23:55:38.92 |
+47:52:47.2 |
HIP 117925 |
10.51 |
| 2026-08-08 00:00 |
23:55:31.62 |
+47:53:31.9 |
HIP 117925 |
10.63 |
| 2026-08-08 12:00 |
23:55:24.25 |
+47:54:16.0 |
HIP 117925 |
10.93 |
| 2026-08-09 00:00 |
23:55:16.83 |
+47:54:59.5 |
HIP 117925 |
11.39 |
| 2026-08-09 12:00 |
23:55:09.34 |
+47:55:42.3 |
HIP 117925 |
12.00 |
| 2026-08-10 00:00 |
23:55:01.80 |
+47:56:24.5 |
HIP 117925 |
12.73 |
| 2026-08-10 12:00 |
23:54:54.20 |
+47:57:06.0 |
HIP 117925 |
13.57 |
| 2026-08-11 00:00 |
23:54:46.54 |
+47:57:46.9 |
HIP 117925 |
14.49 |
| 2026-08-11 12:00 |
23:54:38.82 |
+47:58:27.1 |
HIP 117925 |
15.50 |
| 2026-08-12 00:00 |
23:54:31.04 |
+47:59:06.7 |
HIP 117925 |
16.56 |
| 2026-08-12 12:00 |
23:54:23.21 |
+47:59:45.6 |
HIP 117925 |
17.67 |
| 2026-08-13 00:00 |
23:54:15.33 |
+48:00:23.8 |
HIP 117925 |
18.83 |
| 2026-08-13 12:00 |
23:54:07.39 |
+48:01:01.4 |
HIP 117925 |
20.02 |
| 2026-08-14 00:00 |
23:53:59.39 |
+48:01:38.3 |
HIP 117925 |
21.24 |
| 2026-08-14 12:00 |
23:53:51.34 |
+48:02:14.5 |
HIP 117979 |
22.30 |
| 2026-08-15 00:00 |
23:53:43.24 |
+48:02:50.0 |
HIP 117979 |
23.21 |
| 2026-08-15 12:00 |
23:53:35.09 |
+48:03:24.9 |
HIP 117979 |
24.19 |
| 2026-08-16 00:00 |
23:53:26.88 |
+48:03:59.1 |
HIP 117979 |
25.23 |
| 2026-08-16 12:00 |
23:53:18.62 |
+48:04:32.5 |
HIP 117754 |
24.83 |
| 2026-08-17 00:00 |
23:53:10.31 |
+48:05:05.3 |
HIP 117754 |
24.06 |
| 2026-08-17 12:00 |
23:53:01.95 |
+48:05:37.4 |
HIP 117754 |
23.37 |
| 2026-08-18 00:00 |
23:52:53.55 |
+48:06:08.8 |
HIP 117754 |
22.77 |
| 2026-08-18 12:00 |
23:52:45.09 |
+48:06:39.5 |
HIP 117754 |
22.26 |
| 2026-08-19 00:00 |
23:52:36.59 |
+48:07:09.5 |
HIP 117754 |
21.86 |