메타데이터
| 항목 |
값 |
| Designation |
C/2018 X2 (Fitzsimmons) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-07-08T12:50:12.180480Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:48Z |
| Obs used |
390 |
| NEO |
- |
| M1 |
10.600 |
| K1 |
12.750 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2018-12-08T11:10:09.696000Z |
| Discovery magnitude (MPC) |
19.10 c |
| Discovery observatory (MPC) |
T05 · ATLAS-HKO, Haleakala |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2019-02-10.0000000 |
| e |
0.98628022 |
| q (au) |
2.125879 |
| a (au) |
154.949983 |
| i (deg) |
23.068234 |
| Ω (om, deg) |
340.833210 |
| ω (w, deg) |
162.047045 |
| M (ma, deg) |
359.924099 |
밝기
산란 + 전체 선형
$$
M_a = (10.225 + 5.892\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
10.225 |
| n |
5.892 |
| gf |
0.999 |
| gb |
-0.500 |
| k |
0.800 |
| δ90 |
2.698 |
| 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
천체력
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
19:36:46.34 |
-41:36:37.8 |
HIP 96545 |
13.49 |
| 2026-05-12 12:00 |
19:36:43.01 |
-41:37:10.5 |
HIP 96545 |
14.32 |
| 2026-05-13 00:00 |
19:36:39.60 |
-41:37:43.2 |
HIP 96545 |
15.16 |
| 2026-05-13 12:00 |
19:36:36.13 |
-41:38:15.9 |
HIP 96545 |
16.00 |
| 2026-05-14 00:00 |
19:36:32.59 |
-41:38:48.6 |
HIP 96545 |
16.86 |
| 2026-05-14 12:00 |
19:36:28.98 |
-41:39:21.3 |
HIP 96545 |
17.72 |
| 2026-05-15 00:00 |
19:36:25.31 |
-41:39:53.9 |
HIP 96545 |
18.60 |
| 2026-05-15 12:00 |
19:36:21.57 |
-41:40:26.5 |
HIP 96545 |
19.48 |
| 2026-05-16 00:00 |
19:36:17.76 |
-41:40:59.0 |
HIP 96336 |
20.06 |
| 2026-05-16 12:00 |
19:36:13.88 |
-41:41:31.6 |
HIP 96336 |
20.04 |
| 2026-05-17 00:00 |
19:36:09.94 |
-41:42:04.0 |
HIP 96336 |
20.06 |
| 2026-05-17 12:00 |
19:36:05.93 |
-41:42:36.4 |
HIP 96336 |
20.11 |
| 2026-05-18 00:00 |
19:36:01.86 |
-41:43:08.8 |
HIP 96336 |
20.20 |
| 2026-05-18 12:00 |
19:35:57.72 |
-41:43:41.1 |
HIP 96336 |
20.33 |
| 2026-05-19 00:00 |
19:35:53.52 |
-41:44:13.4 |
HIP 96336 |
20.49 |
| 2026-05-19 12:00 |
19:35:49.25 |
-41:44:45.6 |
HIP 96336 |
20.69 |
| 2026-05-20 00:00 |
19:35:44.92 |
-41:45:17.7 |
HIP 96336 |
20.93 |
| 2026-05-20 12:00 |
19:35:40.52 |
-41:45:49.8 |
HIP 96336 |
21.20 |
| 2026-05-21 00:00 |
19:35:36.07 |
-41:46:21.8 |
HIP 96336 |
21.51 |
| 2026-05-21 12:00 |
19:35:31.55 |
-41:46:53.7 |
HIP 96336 |
21.86 |
| 2026-05-22 00:00 |
19:35:26.96 |
-41:47:25.5 |
HIP 96336 |
22.25 |
| 2026-05-22 12:00 |
19:35:22.32 |
-41:47:57.3 |
HIP 96336 |
22.67 |
| 2026-05-23 00:00 |
19:35:17.61 |
-41:48:28.9 |
HIP 96346 |
22.56 |
| 2026-05-23 12:00 |
19:35:12.85 |
-41:49:00.5 |
HIP 96346 |
22.05 |
| 2026-05-24 00:00 |
19:35:08.02 |
-41:49:32.0 |
HIP 96346 |
21.57 |
| 2026-05-24 12:00 |
19:35:03.13 |
-41:50:03.3 |
HIP 96346 |
21.14 |
| 2026-05-25 00:00 |
19:34:58.18 |
-41:50:34.6 |
HIP 96346 |
20.76 |
| 2026-05-25 12:00 |
19:34:53.18 |
-41:51:05.8 |
HIP 96346 |
20.43 |
| 2026-05-26 00:00 |
19:34:48.11 |
-41:51:36.9 |
HIP 96346 |
20.15 |
| 2026-05-26 12:00 |
19:34:42.99 |
-41:52:07.8 |
HIP 96346 |
19.93 |
| 2026-05-27 00:00 |
19:34:37.81 |
-41:52:38.7 |
HIP 96346 |
19.78 |
| 2026-05-27 12:00 |
19:34:32.57 |
-41:53:09.4 |
HIP 96346 |
19.69 |
| 2026-05-28 00:00 |
19:34:27.28 |
-41:53:40.1 |
HIP 96346 |
19.67 |
| 2026-05-28 12:00 |
19:34:21.92 |
-41:54:10.6 |
HIP 96346 |
19.71 |
| 2026-05-29 00:00 |
19:34:16.52 |
-41:54:40.9 |
HIP 96346 |
19.83 |
| 2026-05-29 12:00 |
19:34:11.05 |
-41:55:11.2 |
HIP 96346 |
20.02 |
| 2026-05-30 00:00 |
19:34:05.53 |
-41:55:41.3 |
HIP 96346 |
20.28 |
| 2026-05-30 12:00 |
19:33:59.96 |
-41:56:11.3 |
HIP 96346 |
20.60 |
| 2026-05-31 00:00 |
19:33:54.33 |
-41:56:41.1 |
HIP 96346 |
21.00 |
| 2026-05-31 12:00 |
19:33:48.65 |
-41:57:10.8 |
HIP 96346 |
21.46 |
| 2026-06-01 00:00 |
19:33:42.92 |
-41:57:40.3 |
HIP 96099 |
21.57 |
| 2026-06-01 12:00 |
19:33:37.13 |
-41:58:09.8 |
HIP 96099 |
20.46 |
| 2026-06-02 00:00 |
19:33:31.29 |
-41:58:39.0 |
HIP 96099 |
19.36 |