메타데이터
| 항목 |
값 |
| Designation |
C/2015 X4 (Elenin) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2015-11-03T11:14:21.828480Z |
| Orbit solution date (soln_date, UTC) |
2022-05-19T21:12:39Z |
| Obs used |
607 |
| NEO |
- |
| M1 |
13.000 |
| K1 |
4.500 |
| PC |
- |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2016-02-01.0000000 |
| e |
0.81280434 |
| q (au) |
3.394686 |
| a (au) |
18.134427 |
| i (deg) |
29.504921 |
| Ω (om, deg) |
262.635812 |
| ω (w, deg) |
176.329174 |
| M (ma, deg) |
1.142681 |
밝기
산란 + 전체 선형
$$
M_a = (11.919 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
11.919 |
| n |
2.000 |
| gf |
0.807 |
| gb |
-0.500 |
| k |
0.997 |
| δ90 |
1.000 |
| 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 |
| 2014-12-22 |
2015-11-02 |
+10.5196 |
-3.568 |
| 2015-12-02 |
2017-03-24 |
-2.7904 |
+1.550 |
log10 r = log10(태양거리/AU), Δ = 지구거리(AU)
천체력
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
14:43:21.27 |
-32:41:28.4 |
HIP 71922 |
9.68 |
| 2026-09-20 12:00 |
14:43:26.74 |
-32:41:27.2 |
HIP 71922 |
10.81 |
| 2026-09-21 00:00 |
14:43:32.25 |
-32:41:26.2 |
HIP 71922 |
11.95 |
| 2026-09-21 12:00 |
14:43:37.79 |
-32:41:25.6 |
HIP 71922 |
13.10 |
| 2026-09-22 00:00 |
14:43:43.36 |
-32:41:25.2 |
HIP 71922 |
14.26 |
| 2026-09-22 12:00 |
14:43:48.97 |
-32:41:25.2 |
HIP 71922 |
15.43 |
| 2026-09-23 00:00 |
14:43:54.62 |
-32:41:25.4 |
HIP 71922 |
16.60 |
| 2026-09-23 12:00 |
14:44:00.30 |
-32:41:25.9 |
HIP 71922 |
17.79 |
| 2026-09-24 00:00 |
14:44:06.01 |
-32:41:26.7 |
HIP 72149 |
18.30 |
| 2026-09-24 12:00 |
14:44:11.75 |
-32:41:27.7 |
HIP 72149 |
17.19 |
| 2026-09-25 00:00 |
14:44:17.53 |
-32:41:29.1 |
HIP 72149 |
16.08 |
| 2026-09-25 12:00 |
14:44:23.34 |
-32:41:30.7 |
HIP 72149 |
14.98 |
| 2026-09-26 00:00 |
14:44:29.19 |
-32:41:32.6 |
HIP 72149 |
13.90 |
| 2026-09-26 12:00 |
14:44:35.07 |
-32:41:34.8 |
HIP 72149 |
12.83 |
| 2026-09-27 00:00 |
14:44:40.98 |
-32:41:37.3 |
HIP 72149 |
11.79 |
| 2026-09-27 12:00 |
14:44:46.92 |
-32:41:40.0 |
HIP 72149 |
10.78 |
| 2026-09-28 00:00 |
14:44:52.89 |
-32:41:43.0 |
HIP 72149 |
9.81 |
| 2026-09-28 12:00 |
14:44:58.89 |
-32:41:46.3 |
HIP 72149 |
8.92 |
| 2026-09-29 00:00 |
14:45:04.93 |
-32:41:49.9 |
HIP 72149 |
8.11 |
| 2026-09-29 12:00 |
14:45:10.99 |
-32:41:53.8 |
HIP 72149 |
7.43 |
| 2026-09-30 00:00 |
14:45:17.08 |
-32:41:57.9 |
HIP 72149 |
6.92 |
| 2026-09-30 12:00 |
14:45:23.21 |
-32:42:02.3 |
HIP 72149 |
6.61 |
| 2026-10-01 00:00 |
14:45:29.36 |
-32:42:07.0 |
HIP 72149 |
6.54 |
| 2026-10-01 12:00 |
14:45:35.55 |
-32:42:11.9 |
HIP 72149 |
6.72 |
| 2026-10-02 00:00 |
14:45:41.76 |
-32:42:17.2 |
HIP 72149 |
7.14 |
| 2026-10-02 12:00 |
14:45:48.00 |
-32:42:22.7 |
HIP 72149 |
7.76 |
| 2026-10-03 00:00 |
14:45:54.27 |
-32:42:28.4 |
HIP 72149 |
8.54 |
| 2026-10-03 12:00 |
14:46:00.57 |
-32:42:34.5 |
HIP 72149 |
9.44 |
| 2026-10-04 00:00 |
14:46:06.89 |
-32:42:40.8 |
HIP 72149 |
10.44 |
| 2026-10-04 12:00 |
14:46:13.24 |
-32:42:47.4 |
HIP 72149 |
11.50 |
| 2026-10-05 00:00 |
14:46:19.62 |
-32:42:54.2 |
HIP 72149 |
12.62 |
| 2026-10-05 12:00 |
14:46:26.03 |
-32:43:01.3 |
HIP 72149 |
13.79 |
| 2026-10-06 00:00 |
14:46:32.46 |
-32:43:08.7 |
HIP 72149 |
14.99 |
| 2026-10-06 12:00 |
14:46:38.92 |
-32:43:16.4 |
HIP 72149 |
16.22 |
| 2026-10-07 00:00 |
14:46:45.41 |
-32:43:24.3 |
HIP 72149 |
17.47 |
| 2026-10-07 12:00 |
14:46:51.92 |
-32:43:32.4 |
HIP 72279 |
18.39 |
| 2026-10-08 00:00 |
14:46:58.45 |
-32:43:40.9 |
HIP 72279 |
18.30 |
| 2026-10-08 12:00 |
14:47:05.01 |
-32:43:49.6 |
HIP 72279 |
18.30 |
| 2026-10-09 00:00 |
14:47:11.59 |
-32:43:58.6 |
HIP 72279 |
18.41 |
| 2026-10-09 12:00 |
14:47:18.20 |
-32:44:07.8 |
HIP 72279 |
18.62 |
| 2026-10-10 00:00 |
14:47:24.83 |
-32:44:17.3 |
HIP 72439 |
17.43 |
| 2026-10-10 12:00 |
14:47:31.49 |
-32:44:27.0 |
HIP 72439 |
16.03 |
| 2026-10-11 00:00 |
14:47:38.16 |
-32:44:37.0 |
HIP 72439 |
14.62 |