메타데이터
| 항목 |
값 |
| 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 궤도요소
| 항목 |
값 |
| 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 |
밝기
산란 + 전체 선형
$$
M_a = (3.987 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
3.987 |
| n |
6.000 |
| gf |
0.897 |
| gb |
-0.891 |
| k |
1.000 |
| δ90 |
4.953 |
| 파라미터 |
기호 |
범위 |
설명 |
| 태양·지구거리 1 AU에서의 절대등급 |
H0 |
-5 to 20 |
혜성의 고유 밝기 |
| 광도 기울기 파라미터 |
n |
2 to 6 |
태양거리 변화에 따른 밝기 변화율 |
| 전방 산란 비대칭 계수 |
gf |
0.8 to 1 |
전방 산란의 강도 |
| 후방 산란 비대칭 계수 |
gb |
-1 to -0.5 |
후방 산란의 강도 |
| 분할 계수 |
k |
0.8 to 1 |
전·후방 산란 기여도 비율 |
| 먼지/가스 밝기 비 |
δ90 |
1 to 10 |
코마에서 먼지 산란 대비 가스 방출의 상대 기여 |
참고: EPSC-DPS2025-160
잔차 (구간 선형)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 시작일 (UTC) |
끝 (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(태양거리/AU), Δ = 지구거리(AU)
천체력
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
13:55:00.89 |
-08:27:04.0 |
HIP 67967 |
10.40 |
| 2026-07-29 12:00 |
13:55:05.90 |
-08:27:27.8 |
HIP 67967 |
9.90 |
| 2026-07-30 00:00 |
13:55:10.99 |
-08:27:52.1 |
HIP 67967 |
9.54 |
| 2026-07-30 12:00 |
13:55:16.17 |
-08:28:16.8 |
HIP 67967 |
9.36 |
| 2026-07-31 00:00 |
13:55:21.44 |
-08:28:42.0 |
HIP 67967 |
9.36 |
| 2026-07-31 12:00 |
13:55:26.79 |
-08:29:07.7 |
HIP 67967 |
9.57 |
| 2026-08-01 00:00 |
13:55:32.24 |
-08:29:33.8 |
HIP 67967 |
9.98 |
| 2026-08-01 12:00 |
13:55:37.77 |
-08:30:00.5 |
HIP 67967 |
10.57 |
| 2026-08-02 00:00 |
13:55:43.39 |
-08:30:27.6 |
HIP 67967 |
11.33 |
| 2026-08-02 12:00 |
13:55:49.09 |
-08:30:55.1 |
HIP 67967 |
12.23 |
| 2026-08-03 00:00 |
13:55:54.89 |
-08:31:23.2 |
HIP 67967 |
13.25 |
| 2026-08-03 12:00 |
13:56:00.76 |
-08:31:51.7 |
HIP 67967 |
14.37 |
| 2026-08-04 00:00 |
13:56:06.73 |
-08:32:20.6 |
HIP 67967 |
15.58 |
| 2026-08-04 12:00 |
13:56:12.78 |
-08:32:50.0 |
HIP 67967 |
16.87 |
| 2026-08-05 00:00 |
13:56:18.91 |
-08:33:19.9 |
HIP 67967 |
18.22 |
| 2026-08-05 12:00 |
13:56:25.14 |
-08:33:50.2 |
HIP 67967 |
19.62 |
| 2026-08-06 00:00 |
13:56:31.44 |
-08:34:20.9 |
HIP 67967 |
21.08 |
| 2026-08-06 12:00 |
13:56:37.83 |
-08:34:52.1 |
HIP 67967 |
22.58 |
| 2026-08-07 00:00 |
13:56:44.31 |
-08:35:23.8 |
HIP 67967 |
24.12 |
| 2026-08-07 12:00 |
13:56:50.86 |
-08:35:55.9 |
HIP 67967 |
25.70 |
| 2026-08-08 00:00 |
13:56:57.51 |
-08:36:28.4 |
HIP 67967 |
27.32 |
| 2026-08-08 12:00 |
13:57:04.23 |
-08:37:01.4 |
HIP 67967 |
28.97 |
| 2026-08-09 00:00 |
13:57:11.04 |
-08:37:34.7 |
HIP 68241 |
29.77 |
| 2026-08-09 12:00 |
13:57:17.93 |
-08:38:08.6 |
HIP 68241 |
28.44 |
| 2026-08-10 00:00 |
13:57:24.90 |
-08:38:42.8 |
HIP 68241 |
27.15 |
| 2026-08-10 12:00 |
13:57:31.96 |
-08:39:17.5 |
HIP 68241 |
25.91 |
| 2026-08-11 00:00 |
13:57:39.10 |
-08:39:52.6 |
HIP 68241 |
24.72 |
| 2026-08-11 12:00 |
13:57:46.31 |
-08:40:28.1 |
HIP 68241 |
23.61 |
| 2026-08-12 00:00 |
13:57:53.61 |
-08:41:04.0 |
HIP 68241 |
22.60 |
| 2026-08-12 12:00 |
13:58:00.99 |
-08:41:40.3 |
HIP 68241 |
21.69 |
| 2026-08-13 00:00 |
13:58:08.45 |
-08:42:17.1 |
HIP 68241 |
20.91 |
| 2026-08-13 12:00 |
13:58:15.99 |
-08:42:54.2 |
HIP 68241 |
20.28 |
| 2026-08-14 00:00 |
13:58:23.61 |
-08:43:31.7 |
HIP 68241 |
19.82 |
| 2026-08-14 12:00 |
13:58:31.31 |
-08:44:09.7 |
HIP 68241 |
19.56 |
| 2026-08-15 00:00 |
13:58:39.09 |
-08:44:48.0 |
HIP 68241 |
19.49 |
| 2026-08-15 12:00 |
13:58:46.94 |
-08:45:26.7 |
HIP 68241 |
19.64 |
| 2026-08-16 00:00 |
13:58:54.87 |
-08:46:05.8 |
HIP 68241 |
20.00 |
| 2026-08-16 12:00 |
13:59:02.88 |
-08:46:45.3 |
HIP 68241 |
20.57 |
| 2026-08-17 00:00 |
13:59:10.96 |
-08:47:25.2 |
HIP 68241 |
21.34 |
| 2026-08-17 12:00 |
13:59:19.13 |
-08:48:05.4 |
HIP 68241 |
22.29 |
| 2026-08-18 00:00 |
13:59:27.36 |
-08:48:46.0 |
HIP 68241 |
23.40 |
| 2026-08-18 12:00 |
13:59:35.67 |
-08:49:27.0 |
HIP 68241 |
24.67 |
| 2026-08-19 00:00 |
13:59:44.06 |
-08:50:08.3 |
HIP 68241 |
26.06 |