메타데이터
| 항목 |
값 |
| Designation |
C/2018 Y1 (Iwamoto) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-02-07T00:44:05.775360Z |
| Orbit solution date (soln_date, UTC) |
2024-01-04T23:42:43Z |
| Obs used |
2771 |
| NEO |
- |
| M1 |
13.600 |
| K1 |
5.250 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2018-12-18T20:11:02.400000Z |
| Discovery magnitude (MPC) |
12.00 R |
| Discovery observatory (MPC) |
872 · Tokushima |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2019-03-03.0000000 |
| e |
0.99107927 |
| q (au) |
1.286994 |
| a (au) |
144.270155 |
| i (deg) |
160.403537 |
| Ω (om, deg) |
147.483562 |
| ω (w, deg) |
358.057218 |
| M (ma, deg) |
0.013633 |
밝기
산란 + 전체 선형
$$
M_a = (13.253 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
13.253 |
| n |
2.000 |
| gf |
0.972 |
| gb |
-0.632 |
| k |
0.984 |
| δ90 |
9.902 |
| 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 |
| 2018-12-18 |
2019-02-07 |
+11.1321 |
-3.457 |
| 2019-02-07 |
2019-12-22 |
+2.9643 |
-1.536 |
log10 r = log10(태양거리/AU), Δ = 지구거리(AU)
천체력
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
23:34:58.95 |
+07:34:37.8 |
HIP 116339 |
22.44 |
| 2026-03-26 12:00 |
23:35:03.88 |
+07:35:09.7 |
HIP 116339 |
22.44 |
| 2026-03-27 00:00 |
23:35:08.80 |
+07:35:41.7 |
HIP 116339 |
22.52 |
| 2026-03-27 12:00 |
23:35:13.71 |
+07:36:13.8 |
HIP 116339 |
22.67 |
| 2026-03-28 00:00 |
23:35:18.61 |
+07:36:45.9 |
HIP 116339 |
22.89 |
| 2026-03-28 12:00 |
23:35:23.49 |
+07:37:18.0 |
HIP 116339 |
23.19 |
| 2026-03-29 00:00 |
23:35:28.37 |
+07:37:50.2 |
HIP 116339 |
23.55 |
| 2026-03-29 12:00 |
23:35:33.23 |
+07:38:22.5 |
HIP 116339 |
23.98 |
| 2026-03-30 00:00 |
23:35:38.08 |
+07:38:54.8 |
HIP 116550 |
23.84 |
| 2026-03-30 12:00 |
23:35:42.92 |
+07:39:27.1 |
HIP 116550 |
22.56 |
| 2026-03-31 00:00 |
23:35:47.74 |
+07:39:59.5 |
HIP 116550 |
21.28 |
| 2026-03-31 12:00 |
23:35:52.55 |
+07:40:31.9 |
HIP 116550 |
20.02 |
| 2026-04-01 00:00 |
23:35:57.35 |
+07:41:04.3 |
HIP 116550 |
18.76 |
| 2026-04-01 12:00 |
23:36:02.13 |
+07:41:36.8 |
HIP 116550 |
17.51 |
| 2026-04-02 00:00 |
23:36:06.90 |
+07:42:09.3 |
HIP 116550 |
16.28 |
| 2026-04-02 12:00 |
23:36:11.65 |
+07:42:41.9 |
HIP 116550 |
15.06 |
| 2026-04-03 00:00 |
23:36:16.39 |
+07:43:14.4 |
HIP 116550 |
13.86 |
| 2026-04-03 12:00 |
23:36:21.11 |
+07:43:47.0 |
HIP 116550 |
12.68 |
| 2026-04-04 00:00 |
23:36:25.82 |
+07:44:19.7 |
HIP 116550 |
11.53 |
| 2026-04-04 12:00 |
23:36:30.51 |
+07:44:52.3 |
HIP 116550 |
10.42 |
| 2026-04-05 00:00 |
23:36:35.18 |
+07:45:25.0 |
HIP 116550 |
9.35 |
| 2026-04-05 12:00 |
23:36:39.84 |
+07:45:57.6 |
HIP 116550 |
8.35 |
| 2026-04-06 00:00 |
23:36:44.48 |
+07:46:30.3 |
HIP 116550 |
7.43 |
| 2026-04-06 12:00 |
23:36:49.11 |
+07:47:03.0 |
HIP 116550 |
6.64 |
| 2026-04-07 00:00 |
23:36:53.72 |
+07:47:35.7 |
HIP 116550 |
6.02 |
| 2026-04-07 12:00 |
23:36:58.30 |
+07:48:08.5 |
HIP 116550 |
5.62 |
| 2026-04-08 00:00 |
23:37:02.88 |
+07:48:41.2 |
HIP 116550 |
5.49 |
| 2026-04-08 12:00 |
23:37:07.43 |
+07:49:13.9 |
HIP 116550 |
5.64 |
| 2026-04-09 00:00 |
23:37:11.96 |
+07:49:46.6 |
HIP 116550 |
6.06 |
| 2026-04-09 12:00 |
23:37:16.48 |
+07:50:19.4 |
HIP 116550 |
6.68 |
| 2026-04-10 00:00 |
23:37:20.97 |
+07:50:52.1 |
HIP 116550 |
7.46 |
| 2026-04-10 12:00 |
23:37:25.45 |
+07:51:24.8 |
HIP 116550 |
8.35 |
| 2026-04-11 00:00 |
23:37:29.90 |
+07:51:57.5 |
HIP 116550 |
9.32 |
| 2026-04-11 12:00 |
23:37:34.34 |
+07:52:30.2 |
HIP 116550 |
10.34 |
| 2026-04-12 00:00 |
23:37:38.76 |
+07:53:02.9 |
HIP 116550 |
11.40 |
| 2026-04-12 12:00 |
23:37:43.15 |
+07:53:35.6 |
HIP 116550 |
12.48 |
| 2026-04-13 00:00 |
23:37:47.52 |
+07:54:08.2 |
HIP 116550 |
13.59 |
| 2026-04-13 12:00 |
23:37:51.87 |
+07:54:40.8 |
HIP 116550 |
14.70 |
| 2026-04-14 00:00 |
23:37:56.20 |
+07:55:13.4 |
HIP 116550 |
15.83 |
| 2026-04-14 12:00 |
23:38:00.51 |
+07:55:46.0 |
HIP 116550 |
16.96 |
| 2026-04-15 00:00 |
23:38:04.79 |
+07:56:18.5 |
HIP 116550 |
18.09 |
| 2026-04-15 12:00 |
23:38:09.06 |
+07:56:51.1 |
HIP 116550 |
19.23 |
| 2026-04-16 00:00 |
23:38:13.29 |
+07:57:23.5 |
HIP 116550 |
20.37 |