메타데이터
| 항목 |
값 |
| Designation |
238P/Read |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2022-06-05T10:21:50.189760Z |
| Orbit solution date (soln_date, UTC) |
2024-05-30T15:51:09Z |
| Obs used |
119 |
| NEO |
- |
| M1 |
8.300 |
| K1 |
29.750 |
| PC |
0.030 |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2022-09-15.0000000 |
| e |
0.25167358 |
| q (au) |
2.369349 |
| a (au) |
3.166197 |
| i (deg) |
1.264088 |
| Ω (om, deg) |
51.625454 |
| ω (w, deg) |
324.206807 |
| M (ma, deg) |
17.768666 |
밝기
산란 + 전체 선형
$$
M_a = (13.654 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
13.654 |
| n |
6.000 |
| gf |
0.972 |
| gb |
-0.872 |
| k |
1.000 |
| δ90 |
8.980 |
| 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 |
| 2021-06-11 |
2021-11-26 |
+2.0364 |
+0.529 |
log10 r = log10(태양거리/AU), Δ = 지구거리(AU)
천체력
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
16:24:15.07 |
-21:58:10.9 |
HIP 80440 |
13.66 |
| 2026-05-12 12:00 |
16:23:52.90 |
-21:57:28.8 |
HIP 80440 |
18.70 |
| 2026-05-13 00:00 |
16:23:30.55 |
-21:56:46.1 |
HIP 80440 |
23.85 |
| 2026-05-13 12:00 |
16:23:08.05 |
-21:56:02.8 |
HIP 80130 |
26.90 |
| 2026-05-14 00:00 |
16:22:45.40 |
-21:55:18.9 |
HIP 80130 |
22.52 |
| 2026-05-14 12:00 |
16:22:22.59 |
-21:54:34.5 |
HIP 80130 |
18.60 |
| 2026-05-15 00:00 |
16:21:59.64 |
-21:53:49.5 |
HIP 80130 |
15.53 |
| 2026-05-15 12:00 |
16:21:36.55 |
-21:53:03.9 |
HIP 80085 |
12.63 |
| 2026-05-16 00:00 |
16:21:13.32 |
-21:52:17.9 |
HIP 80085 |
7.21 |
| 2026-05-16 12:00 |
16:20:49.96 |
-21:51:31.2 |
HIP 80085 |
1.89 |
| 2026-05-17 00:00 |
16:20:26.48 |
-21:50:44.1 |
HIP 80085 |
3.91 |
| 2026-05-17 12:00 |
16:20:02.88 |
-21:49:56.4 |
HIP 80085 |
9.39 |
| 2026-05-18 00:00 |
16:19:39.17 |
-21:49:08.3 |
HIP 80085 |
14.94 |
| 2026-05-18 12:00 |
16:19:15.35 |
-21:48:19.6 |
HIP 79910 |
15.28 |
| 2026-05-19 00:00 |
16:18:51.43 |
-21:47:30.4 |
HIP 79910 |
12.28 |
| 2026-05-19 12:00 |
16:18:27.40 |
-21:46:40.8 |
HIP 79910 |
11.44 |
| 2026-05-20 00:00 |
16:18:03.29 |
-21:45:50.6 |
HIP 79839 |
9.00 |
| 2026-05-20 12:00 |
16:17:39.09 |
-21:45:00.1 |
HIP 79839 |
9.21 |
| 2026-05-21 00:00 |
16:17:14.81 |
-21:44:09.0 |
HIP 79839 |
12.39 |
| 2026-05-21 12:00 |
16:16:50.46 |
-21:43:17.5 |
HIP 79839 |
16.96 |
| 2026-05-22 00:00 |
16:16:26.03 |
-21:42:25.6 |
HIP 79839 |
22.09 |
| 2026-05-22 12:00 |
16:16:01.54 |
-21:41:33.3 |
HIP 79785 |
26.84 |
| 2026-05-23 00:00 |
16:15:37.00 |
-21:40:40.6 |
HIP 79644 |
27.19 |
| 2026-05-23 12:00 |
16:15:12.40 |
-21:39:47.4 |
HIP 79524 |
26.59 |
| 2026-05-24 00:00 |
16:14:47.75 |
-21:38:53.9 |
HIP 79524 |
21.61 |
| 2026-05-24 12:00 |
16:14:23.06 |
-21:38:00.0 |
HIP 79524 |
17.16 |
| 2026-05-25 00:00 |
16:13:58.33 |
-21:37:05.7 |
HIP 79524 |
13.74 |
| 2026-05-25 12:00 |
16:13:33.57 |
-21:36:11.1 |
HIP 79524 |
12.29 |
| 2026-05-26 00:00 |
16:13:08.79 |
-21:35:16.1 |
HIP 79524 |
13.46 |
| 2026-05-26 12:00 |
16:12:43.98 |
-21:34:20.8 |
HIP 79524 |
16.72 |
| 2026-05-27 00:00 |
16:12:19.16 |
-21:33:25.1 |
HIP 79335 |
11.71 |
| 2026-05-27 12:00 |
16:11:54.33 |
-21:32:29.2 |
HIP 79335 |
6.41 |
| 2026-05-28 00:00 |
16:11:29.50 |
-21:31:33.0 |
HIP 79335 |
3.68 |
| 2026-05-28 12:00 |
16:11:04.66 |
-21:30:36.5 |
HIP 79335 |
7.37 |
| 2026-05-29 00:00 |
16:10:39.83 |
-21:29:39.7 |
HIP 79335 |
12.80 |
| 2026-05-29 12:00 |
16:10:15.01 |
-21:28:42.6 |
HIP 79300 |
15.56 |
| 2026-05-30 00:00 |
16:09:50.21 |
-21:27:45.4 |
HIP 79300 |
19.48 |
| 2026-05-30 12:00 |
16:09:25.43 |
-21:26:47.8 |
HIP 79020 |
23.55 |
| 2026-05-31 00:00 |
16:09:00.68 |
-21:25:50.1 |
HIP 79020 |
17.73 |
| 2026-05-31 12:00 |
16:08:35.96 |
-21:24:52.2 |
HIP 79020 |
11.94 |
| 2026-06-01 00:00 |
16:08:11.28 |
-21:23:54.1 |
HIP 79020 |
6.25 |
| 2026-06-01 12:00 |
16:07:46.64 |
-21:22:55.8 |
HIP 79020 |
1.85 |
| 2026-06-02 00:00 |
16:07:22.05 |
-21:21:57.4 |
HIP 79020 |
5.94 |