| Parameter |
Value |
| Designation |
P/2020 W1 (Rankin) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2020-04-04T04:06:18.002880Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:34:15Z |
| Obs used |
89 |
| NEO |
- |
| M1 |
10.400 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2020-11-16T08:16:49.900800Z |
| Discovery magnitude (MPC) |
20.90 G |
| Discovery observatory (MPC) |
G96 · University of Arizona Mt. Lemmon Survey |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2020-11-08.0000000 |
| e |
0.26491783 |
| q (au) |
5.287627 |
| a (au) |
7.193246 |
| i (deg) |
10.792086 |
| Ω (om, deg) |
124.257217 |
| ω (w, deg) |
264.771285 |
| M (ma, deg) |
11.128390 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.338 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.338 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
10.000 |
| 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) |
| 2026-07-29 00:00 |
11:14:23.41 |
+12:30:16.5 |
HIP 54969 |
16.99 |
| 2026-07-29 12:00 |
11:14:36.34 |
+12:28:49.2 |
HIP 54969 |
13.56 |
| 2026-07-30 00:00 |
11:14:49.33 |
+12:27:21.8 |
HIP 54969 |
10.16 |
| 2026-07-30 12:00 |
11:15:02.36 |
+12:25:54.1 |
HIP 54969 |
6.83 |
| 2026-07-31 00:00 |
11:15:15.45 |
+12:24:26.3 |
HIP 54969 |
3.81 |
| 2026-07-31 12:00 |
11:15:28.58 |
+12:22:58.3 |
HIP 54969 |
2.68 |
| 2026-08-01 00:00 |
11:15:41.75 |
+12:21:30.1 |
HIP 54969 |
4.98 |
| 2026-08-01 12:00 |
11:15:54.97 |
+12:20:01.8 |
HIP 54969 |
8.22 |
| 2026-08-02 00:00 |
11:16:08.24 |
+12:18:33.3 |
HIP 54969 |
11.66 |
| 2026-08-02 12:00 |
11:16:21.56 |
+12:17:04.6 |
HIP 54969 |
15.16 |
| 2026-08-03 00:00 |
11:16:34.91 |
+12:15:35.8 |
HIP 55167 |
18.58 |
| 2026-08-03 12:00 |
11:16:48.32 |
+12:14:06.8 |
HIP 55167 |
16.57 |
| 2026-08-04 00:00 |
11:17:01.76 |
+12:12:37.6 |
HIP 55167 |
15.15 |
| 2026-08-04 12:00 |
11:17:15.26 |
+12:11:08.3 |
HIP 55167 |
14.50 |
| 2026-08-05 00:00 |
11:17:28.79 |
+12:09:38.9 |
HIP 55167 |
14.74 |
| 2026-08-05 12:00 |
11:17:42.37 |
+12:08:09.3 |
HIP 55209 |
13.11 |
| 2026-08-06 00:00 |
11:17:55.98 |
+12:06:39.6 |
HIP 55209 |
9.75 |
| 2026-08-06 12:00 |
11:18:09.64 |
+12:05:09.7 |
HIP 55209 |
6.69 |
| 2026-08-07 00:00 |
11:18:23.35 |
+12:03:39.7 |
HIP 55209 |
4.62 |
| 2026-08-07 12:00 |
11:18:37.09 |
+12:02:09.5 |
HIP 55209 |
4.99 |
| 2026-08-08 00:00 |
11:18:50.87 |
+12:00:39.3 |
HIP 55209 |
7.46 |
| 2026-08-08 12:00 |
11:19:04.69 |
+11:59:08.9 |
HIP 55209 |
10.68 |
| 2026-08-09 00:00 |
11:19:18.55 |
+11:57:38.4 |
HIP 55351 |
12.63 |
| 2026-08-09 12:00 |
11:19:32.45 |
+11:56:07.7 |
HIP 55351 |
10.71 |
| 2026-08-10 00:00 |
11:19:46.39 |
+11:54:37.0 |
HIP 55351 |
9.86 |
| 2026-08-10 12:00 |
11:20:00.37 |
+11:53:06.1 |
HIP 55351 |
10.38 |
| 2026-08-11 00:00 |
11:20:14.38 |
+11:51:35.2 |
HIP 55351 |
12.10 |
| 2026-08-11 12:00 |
11:20:28.43 |
+11:50:04.1 |
HIP 55351 |
14.60 |
| 2026-08-12 00:00 |
11:20:42.52 |
+11:48:32.9 |
HIP 55351 |
17.56 |
| 2026-08-12 12:00 |
11:20:56.64 |
+11:47:01.7 |
HIP 55351 |
20.79 |
| 2026-08-13 00:00 |
11:21:10.80 |
+11:45:30.3 |
HIP 55351 |
24.19 |
| 2026-08-13 12:00 |
11:21:24.99 |
+11:43:58.9 |
HIP 55461 |
24.72 |
| 2026-08-14 00:00 |
11:21:39.21 |
+11:42:27.4 |
HIP 55461 |
23.30 |
| 2026-08-14 12:00 |
11:21:53.47 |
+11:40:55.8 |
HIP 55461 |
22.44 |
| 2026-08-15 00:00 |
11:22:07.76 |
+11:39:24.1 |
HIP 55461 |
22.21 |
| 2026-08-15 12:00 |
11:22:22.08 |
+11:37:52.4 |
HIP 55461 |
22.64 |
| 2026-08-16 00:00 |
11:22:36.43 |
+11:36:20.6 |
HIP 55461 |
23.69 |
| 2026-08-16 12:00 |
11:22:50.82 |
+11:34:48.7 |
HIP 55461 |
25.29 |
| 2026-08-17 00:00 |
11:23:05.23 |
+11:33:16.8 |
HIP 55461 |
27.35 |
| 2026-08-17 12:00 |
11:23:19.68 |
+11:31:44.8 |
HIP 55716 |
25.04 |
| 2026-08-18 00:00 |
11:23:34.15 |
+11:30:12.8 |
HIP 55716 |
21.25 |
| 2026-08-18 12:00 |
11:23:48.65 |
+11:28:40.7 |
HIP 55716 |
17.47 |
| 2026-08-19 00:00 |
11:24:03.18 |
+11:27:08.6 |
HIP 55716 |
13.74 |