| Parameter |
Value |
| Designation |
P/2020 V4 (Rankin) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2021-07-17T22:00:33.958080Z |
| Orbit solution date (soln_date, UTC) |
2025-09-09T12:42:49Z |
| Obs used |
619 |
| NEO |
- |
| M1 |
6.900 |
| K1 |
12.250 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2020-11-15T08:54:34.099200Z |
| Discovery magnitude (MPC) |
19.23 G |
| Discovery observatory (MPC) |
G96 · University of Arizona Mt. Lemmon Survey |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2021-07-15.0000000 |
| e |
0.44887531 |
| q (au) |
5.148536 |
| a (au) |
9.341871 |
| i (deg) |
14.243119 |
| Ω (om, deg) |
203.507931 |
| ω (w, deg) |
256.995659 |
| M (ma, deg) |
359.899307 |
Magnitude
Scatter + Global Linear
$$
M_a = (3.987 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
3.987 |
| n |
6.000 |
| gf |
0.897 |
| gb |
-0.891 |
| k |
1.000 |
| δ90 |
4.953 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2015-10-10 |
2019-11-02 |
-11.2590 |
+10.593 |
| 2019-11-02 |
2021-04-21 |
+31.2873 |
-22.459 |
| 2021-08-30 |
2023-03-21 |
+28.4984 |
-21.118 |
| 2023-03-21 |
2024-03-17 |
-8.3408 |
+7.841 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
14:10:55.73 |
-09:44:12.3 |
HIP 69363 |
20.07 |
| 2026-09-20 12:00 |
14:11:08.01 |
-09:45:09.9 |
HIP 69363 |
17.26 |
| 2026-09-21 00:00 |
14:11:20.34 |
-09:46:07.7 |
HIP 69363 |
14.58 |
| 2026-09-21 12:00 |
14:11:32.70 |
-09:47:05.5 |
HIP 69363 |
12.15 |
| 2026-09-22 00:00 |
14:11:45.11 |
-09:48:03.5 |
HIP 69363 |
10.14 |
| 2026-09-22 12:00 |
14:11:57.57 |
-09:49:01.6 |
HIP 69363 |
8.87 |
| 2026-09-23 00:00 |
14:12:10.06 |
-09:49:59.9 |
HIP 69403 |
7.01 |
| 2026-09-23 12:00 |
14:12:22.60 |
-09:50:58.2 |
HIP 69403 |
4.04 |
| 2026-09-24 00:00 |
14:12:35.17 |
-09:51:56.7 |
HIP 69403 |
2.10 |
| 2026-09-24 12:00 |
14:12:47.79 |
-09:52:55.2 |
HIP 69403 |
3.70 |
| 2026-09-25 00:00 |
14:13:00.45 |
-09:53:53.9 |
HIP 69403 |
6.65 |
| 2026-09-25 12:00 |
14:13:13.14 |
-09:54:52.7 |
HIP 69403 |
9.82 |
| 2026-09-26 00:00 |
14:13:25.88 |
-09:55:51.6 |
HIP 69403 |
13.05 |
| 2026-09-26 12:00 |
14:13:38.65 |
-09:56:50.6 |
HIP 69403 |
16.31 |
| 2026-09-27 00:00 |
14:13:51.47 |
-09:57:49.6 |
HIP 69403 |
19.59 |
| 2026-09-27 12:00 |
14:14:04.32 |
-09:58:48.8 |
HIP 69403 |
22.89 |
| 2026-09-28 00:00 |
14:14:17.20 |
-09:59:48.1 |
HIP 69685 |
23.29 |
| 2026-09-28 12:00 |
14:14:30.13 |
-10:00:47.4 |
HIP 69685 |
20.00 |
| 2026-09-29 00:00 |
14:14:43.09 |
-10:01:46.8 |
HIP 69685 |
16.72 |
| 2026-09-29 12:00 |
14:14:56.09 |
-10:02:46.3 |
HIP 69685 |
13.45 |
| 2026-09-30 00:00 |
14:15:09.12 |
-10:03:45.9 |
HIP 69685 |
10.24 |
| 2026-09-30 12:00 |
14:15:22.18 |
-10:04:45.5 |
HIP 69685 |
7.15 |
| 2026-10-01 00:00 |
14:15:35.29 |
-10:05:45.3 |
HIP 69685 |
4.48 |
| 2026-10-01 12:00 |
14:15:48.42 |
-10:06:45.1 |
HIP 69685 |
3.43 |
| 2026-10-02 00:00 |
14:16:01.59 |
-10:07:44.9 |
HIP 69685 |
5.14 |
| 2026-10-02 12:00 |
14:16:14.79 |
-10:08:44.8 |
HIP 69685 |
8.01 |
| 2026-10-03 00:00 |
14:16:28.03 |
-10:09:44.8 |
HIP 69685 |
11.19 |
| 2026-10-03 12:00 |
14:16:41.30 |
-10:10:44.8 |
HIP 69685 |
14.48 |
| 2026-10-04 00:00 |
14:16:54.60 |
-10:11:44.9 |
HIP 69685 |
17.82 |
| 2026-10-04 12:00 |
14:17:07.93 |
-10:12:45.0 |
HIP 69685 |
21.20 |
| 2026-10-05 00:00 |
14:17:21.29 |
-10:13:45.2 |
HIP 69685 |
24.60 |
| 2026-10-05 12:00 |
14:17:34.68 |
-10:14:45.4 |
HIP 69685 |
28.01 |
| 2026-10-06 00:00 |
14:17:48.11 |
-10:15:45.6 |
HIP 69976 |
28.43 |
| 2026-10-06 12:00 |
14:18:01.56 |
-10:16:45.9 |
HIP 69976 |
25.51 |
| 2026-10-07 00:00 |
14:18:15.04 |
-10:17:46.2 |
HIP 69976 |
22.73 |
| 2026-10-07 12:00 |
14:18:28.55 |
-10:18:46.5 |
HIP 69976 |
20.15 |
| 2026-10-08 00:00 |
14:18:42.08 |
-10:19:46.9 |
HIP 69976 |
17.88 |
| 2026-10-08 12:00 |
14:18:55.65 |
-10:20:47.3 |
HIP 69976 |
16.05 |
| 2026-10-09 00:00 |
14:19:09.24 |
-10:21:47.7 |
HIP 69976 |
14.82 |
| 2026-10-09 12:00 |
14:19:22.86 |
-10:22:48.1 |
HIP 69976 |
14.36 |
| 2026-10-10 00:00 |
14:19:36.50 |
-10:23:48.5 |
HIP 69976 |
14.74 |
| 2026-10-10 12:00 |
14:19:50.17 |
-10:24:48.9 |
HIP 69976 |
15.90 |
| 2026-10-11 00:00 |
14:20:03.86 |
-10:25:49.3 |
HIP 69976 |
17.70 |