C/2017 E4 (Lovejoy)
메타데이터
| 항목 |
값 |
| Designation |
C/2017 E4 (Lovejoy) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-04-23T07:32:57.215040Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:31Z |
| Obs used |
642 |
| NEO |
- |
| M1 |
15.600 |
| K1 |
29.750 |
| PC |
- |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2017-03-31.0000000 |
| e |
0.99896241 |
| q (au) |
0.493573 |
| a (au) |
475.690786 |
| i (deg) |
88.186837 |
| Ω (om, deg) |
223.171811 |
| ω (w, deg) |
87.244054 |
| M (ma, deg) |
359.997785 |
밝기
산란 + 전체 선형
$$
M_a = (15.265 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
15.265 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| k |
1.000 |
| δ90 |
10.000 |
| 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 |
| 2017-03-09 |
2017-03-27 |
+15.0652 |
-0.620 |
| 2017-03-27 |
2017-04-23 |
-14.4941 |
-4.028 |
log10 r = log10(태양거리/AU), Δ = 지구거리(AU)
천체력
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
04:26:28.41 |
-51:13:20.5 |
HIP 20813 |
11.34 |
| 2026-02-03 12:00 |
04:26:25.24 |
-51:12:17.3 |
HIP 20813 |
12.23 |
| 2026-02-04 00:00 |
04:26:22.14 |
-51:11:13.8 |
HIP 20813 |
13.16 |
| 2026-02-04 12:00 |
04:26:19.11 |
-51:10:10.1 |
HIP 20813 |
14.12 |
| 2026-02-05 00:00 |
04:26:16.15 |
-51:09:06.0 |
HIP 20813 |
15.10 |
| 2026-02-05 12:00 |
04:26:13.26 |
-51:08:01.8 |
HIP 20813 |
16.10 |
| 2026-02-06 00:00 |
04:26:10.44 |
-51:06:57.3 |
HIP 20618 |
16.40 |
| 2026-02-06 12:00 |
04:26:07.68 |
-51:05:52.5 |
HIP 20618 |
15.30 |
| 2026-02-07 00:00 |
04:26:05.00 |
-51:04:47.5 |
HIP 20618 |
14.21 |
| 2026-02-07 12:00 |
04:26:02.38 |
-51:03:42.3 |
HIP 20618 |
13.14 |
| 2026-02-08 00:00 |
04:25:59.84 |
-51:02:36.9 |
HIP 20618 |
12.09 |
| 2026-02-08 12:00 |
04:25:57.36 |
-51:01:31.2 |
HIP 20618 |
11.08 |
| 2026-02-09 00:00 |
04:25:54.95 |
-51:00:25.3 |
HIP 20618 |
10.10 |
| 2026-02-09 12:00 |
04:25:52.62 |
-50:59:19.2 |
HIP 20618 |
9.16 |
| 2026-02-10 00:00 |
04:25:50.35 |
-50:58:12.9 |
HIP 20618 |
8.30 |
| 2026-02-10 12:00 |
04:25:48.15 |
-50:57:06.5 |
HIP 20618 |
7.53 |
| 2026-02-11 00:00 |
04:25:46.02 |
-50:55:59.8 |
HIP 20618 |
6.87 |
| 2026-02-11 12:00 |
04:25:43.97 |
-50:54:52.9 |
HIP 20618 |
6.37 |
| 2026-02-12 00:00 |
04:25:41.98 |
-50:53:45.9 |
HIP 20618 |
6.07 |
| 2026-02-12 12:00 |
04:25:40.06 |
-50:52:38.6 |
HIP 20618 |
5.99 |
| 2026-02-13 00:00 |
04:25:38.21 |
-50:51:31.3 |
HIP 20618 |
6.14 |
| 2026-02-13 12:00 |
04:25:36.44 |
-50:50:23.7 |
HIP 20618 |
6.51 |
| 2026-02-14 00:00 |
04:25:34.73 |
-50:49:16.0 |
HIP 20618 |
7.07 |
| 2026-02-14 12:00 |
04:25:33.09 |
-50:48:08.1 |
HIP 20618 |
7.76 |
| 2026-02-15 00:00 |
04:25:31.53 |
-50:47:00.1 |
HIP 20618 |
8.57 |
| 2026-02-15 12:00 |
04:25:30.03 |
-50:45:52.0 |
HIP 20618 |
9.46 |
| 2026-02-16 00:00 |
04:25:28.61 |
-50:44:43.7 |
HIP 20606 |
9.54 |
| 2026-02-16 12:00 |
04:25:27.25 |
-50:43:35.3 |
HIP 20606 |
8.53 |
| 2026-02-17 00:00 |
04:25:25.97 |
-50:42:26.8 |
HIP 20606 |
7.58 |
| 2026-02-17 12:00 |
04:25:24.76 |
-50:41:18.1 |
HIP 20606 |
6.71 |
| 2026-02-18 00:00 |
04:25:23.61 |
-50:40:09.4 |
HIP 20606 |
5.93 |
| 2026-02-18 12:00 |
04:25:22.54 |
-50:39:00.5 |
HIP 20606 |
5.32 |
| 2026-02-19 00:00 |
04:25:21.54 |
-50:37:51.6 |
HIP 20606 |
4.91 |
| 2026-02-19 12:00 |
04:25:20.60 |
-50:36:42.5 |
HIP 20606 |
4.77 |
| 2026-02-20 00:00 |
04:25:19.74 |
-50:35:33.4 |
HIP 20606 |
4.92 |
| 2026-02-20 12:00 |
04:25:18.95 |
-50:34:24.2 |
HIP 20606 |
5.33 |
| 2026-02-21 00:00 |
04:25:18.23 |
-50:33:14.9 |
HIP 20606 |
5.96 |
| 2026-02-21 12:00 |
04:25:17.57 |
-50:32:05.6 |
HIP 20606 |
6.73 |
| 2026-02-22 00:00 |
04:25:16.99 |
-50:30:56.2 |
HIP 20606 |
7.61 |
| 2026-02-22 12:00 |
04:25:16.48 |
-50:29:46.7 |
HIP 20606 |
8.57 |
| 2026-02-23 00:00 |
04:25:16.03 |
-50:28:37.2 |
HIP 20606 |
9.57 |
| 2026-02-23 12:00 |
04:25:15.66 |
-50:27:27.7 |
HIP 20606 |
10.61 |
| 2026-02-24 00:00 |
04:25:15.36 |
-50:26:18.1 |
HIP 20606 |
11.68 |