메타데이터
| 항목 |
값 |
| Designation |
C/2017 Y2 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2020-11-04T13:33:04.429440Z |
| Orbit solution date (soln_date, UTC) |
2024-02-25T22:12:25Z |
| Obs used |
961 |
| NEO |
- |
| M1 |
8.600 |
| K1 |
8.000 |
| PC |
0.030 |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2020-09-02.0000000 |
| e |
1.00096403 |
| q (au) |
4.632068 |
| a (au) |
-4804.896119 |
| i (deg) |
128.421418 |
| Ω (om, deg) |
65.986420 |
| ω (w, deg) |
147.860404 |
| M (ma, deg) |
-0.000188 |
밝기
산란 + 전체 선형
$$
M_a = (8.196 + 3.722\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
8.196 |
| n |
3.722 |
| gf |
0.956 |
| gb |
-0.841 |
| k |
0.994 |
| δ90 |
9.998 |
| 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 |
| 2017-12-24 |
2020-10-30 |
+1.7402 |
-1.104 |
| 2020-11-05 |
2022-02-23 |
-10.1087 |
+6.757 |
| 2022-02-23 |
2022-07-31 |
+14.3389 |
-12.242 |
log10 r = log10(태양거리/AU), Δ = 지구거리(AU)
천체력
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
09:39:07.53 |
-40:57:33.6 |
HIP 47425 |
9.88 |
| 2026-06-01 12:00 |
09:39:08.67 |
-40:55:56.6 |
HIP 47428 |
9.87 |
| 2026-06-02 00:00 |
09:39:09.89 |
-40:54:20.1 |
HIP 47428 |
8.69 |
| 2026-06-02 12:00 |
09:39:11.19 |
-40:52:44.1 |
HIP 47428 |
7.66 |
| 2026-06-03 00:00 |
09:39:12.57 |
-40:51:08.7 |
HIP 47428 |
6.86 |
| 2026-06-03 12:00 |
09:39:14.03 |
-40:49:33.9 |
HIP 47428 |
6.35 |
| 2026-06-04 00:00 |
09:39:15.57 |
-40:47:59.7 |
HIP 47428 |
6.21 |
| 2026-06-04 12:00 |
09:39:17.18 |
-40:46:26.0 |
HIP 47428 |
6.45 |
| 2026-06-05 00:00 |
09:39:18.87 |
-40:44:52.9 |
HIP 47428 |
7.04 |
| 2026-06-05 12:00 |
09:39:20.64 |
-40:43:20.4 |
HIP 47428 |
7.89 |
| 2026-06-06 00:00 |
09:39:22.48 |
-40:41:48.5 |
HIP 47428 |
8.92 |
| 2026-06-06 12:00 |
09:39:24.39 |
-40:40:17.2 |
HIP 47428 |
10.08 |
| 2026-06-07 00:00 |
09:39:26.39 |
-40:38:46.5 |
HIP 47428 |
11.32 |
| 2026-06-07 12:00 |
09:39:28.45 |
-40:37:16.4 |
HIP 47428 |
12.61 |
| 2026-06-08 00:00 |
09:39:30.59 |
-40:35:46.9 |
HIP 47428 |
13.95 |
| 2026-06-08 12:00 |
09:39:32.81 |
-40:34:18.0 |
HIP 47486 |
14.43 |
| 2026-06-09 00:00 |
09:39:35.10 |
-40:32:49.8 |
HIP 47486 |
13.97 |
| 2026-06-09 12:00 |
09:39:37.46 |
-40:31:22.1 |
HIP 47486 |
13.65 |
| 2026-06-10 00:00 |
09:39:39.89 |
-40:29:55.1 |
HIP 47486 |
13.49 |
| 2026-06-10 12:00 |
09:39:42.39 |
-40:28:28.7 |
HIP 47486 |
13.47 |
| 2026-06-11 00:00 |
09:39:44.97 |
-40:27:03.0 |
HIP 47486 |
13.61 |
| 2026-06-11 12:00 |
09:39:47.61 |
-40:25:37.9 |
HIP 47486 |
13.90 |
| 2026-06-12 00:00 |
09:39:50.33 |
-40:24:13.5 |
HIP 47486 |
14.32 |
| 2026-06-12 12:00 |
09:39:53.12 |
-40:22:49.7 |
HIP 47486 |
14.86 |
| 2026-06-13 00:00 |
09:39:55.97 |
-40:21:26.5 |
HIP 47486 |
15.51 |
| 2026-06-13 12:00 |
09:39:58.90 |
-40:20:04.0 |
HIP 47486 |
16.25 |
| 2026-06-14 00:00 |
09:40:01.89 |
-40:18:42.2 |
HIP 47456 |
15.92 |
| 2026-06-14 12:00 |
09:40:04.95 |
-40:17:21.1 |
HIP 47456 |
14.46 |
| 2026-06-15 00:00 |
09:40:08.08 |
-40:16:00.6 |
HIP 47456 |
13.01 |
| 2026-06-15 12:00 |
09:40:11.28 |
-40:14:40.8 |
HIP 47456 |
11.57 |
| 2026-06-16 00:00 |
09:40:14.54 |
-40:13:21.7 |
HIP 47456 |
10.15 |
| 2026-06-16 12:00 |
09:40:17.87 |
-40:12:03.3 |
HIP 47456 |
8.75 |
| 2026-06-17 00:00 |
09:40:21.26 |
-40:10:45.5 |
HIP 47456 |
7.38 |
| 2026-06-17 12:00 |
09:40:24.72 |
-40:09:28.5 |
HIP 47456 |
6.06 |
| 2026-06-18 00:00 |
09:40:28.24 |
-40:08:12.1 |
HIP 47456 |
4.82 |
| 2026-06-18 12:00 |
09:40:31.82 |
-40:06:56.5 |
HIP 47456 |
3.75 |
| 2026-06-19 00:00 |
09:40:35.47 |
-40:05:41.5 |
HIP 47456 |
3.02 |
| 2026-06-19 12:00 |
09:40:39.18 |
-40:04:27.3 |
HIP 47456 |
2.88 |
| 2026-06-20 00:00 |
09:40:42.95 |
-40:03:13.7 |
HIP 47456 |
3.42 |
| 2026-06-20 12:00 |
09:40:46.78 |
-40:02:00.9 |
HIP 47456 |
4.38 |
| 2026-06-21 00:00 |
09:40:50.68 |
-40:00:48.8 |
HIP 47456 |
5.54 |
| 2026-06-21 12:00 |
09:40:54.63 |
-39:59:37.4 |
HIP 47456 |
6.81 |
| 2026-06-22 00:00 |
09:40:58.64 |
-39:58:26.7 |
HIP 47456 |
8.12 |