메타데이터
| 항목 |
값 |
| Designation |
C/2015 XY1 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2018-04-29T23:09:25.130880Z |
| Orbit solution date (soln_date, UTC) |
2022-07-31T01:42:27Z |
| Obs used |
741 |
| NEO |
- |
| M1 |
6.400 |
| K1 |
8.250 |
| PC |
0.030 |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2018-03-20.0000000 |
| e |
1.00401907 |
| q (au) |
7.927954 |
| a (au) |
-1972.582314 |
| i (deg) |
148.846771 |
| Ω (om, deg) |
281.616004 |
| ω (w, deg) |
196.354336 |
| M (ma, deg) |
-0.000461 |
밝기
산란 + 전체 선형
$$
M_a = (-0.855 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
-0.855 |
| n |
6.000 |
| gf |
0.882 |
| gb |
-0.939 |
| k |
1.000 |
| δ90 |
3.868 |
| 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) |
| 2026-07-29 00:00 |
00:02:43.98 |
-32:05:28.8 |
HIP 104 |
21.48 |
| 2026-07-29 12:00 |
00:02:38.08 |
-32:06:36.9 |
HIP 104 |
21.09 |
| 2026-07-30 00:00 |
00:02:32.12 |
-32:07:44.9 |
HIP 104 |
20.83 |
| 2026-07-30 12:00 |
00:02:26.11 |
-32:08:52.9 |
HIP 104 |
20.69 |
| 2026-07-31 00:00 |
00:02:20.05 |
-32:10:00.9 |
HIP 104 |
20.68 |
| 2026-07-31 12:00 |
00:02:13.93 |
-32:11:08.8 |
HIP 104 |
20.81 |
| 2026-08-01 00:00 |
00:02:07.76 |
-32:12:16.7 |
HIP 104 |
21.08 |
| 2026-08-01 12:00 |
00:02:01.54 |
-32:13:24.5 |
HIP 104 |
21.47 |
| 2026-08-02 00:00 |
00:01:55.27 |
-32:14:32.3 |
HIP 104 |
21.99 |
| 2026-08-02 12:00 |
00:01:48.95 |
-32:15:40.0 |
HIP 104 |
22.63 |
| 2026-08-03 00:00 |
00:01:42.57 |
-32:16:47.6 |
HIP 104 |
23.38 |
| 2026-08-03 12:00 |
00:01:36.14 |
-32:17:55.2 |
HIP 118304 |
24.15 |
| 2026-08-04 00:00 |
00:01:29.66 |
-32:19:02.7 |
HIP 118304 |
23.10 |
| 2026-08-04 12:00 |
00:01:23.14 |
-32:20:10.1 |
HIP 118304 |
22.14 |
| 2026-08-05 00:00 |
00:01:16.56 |
-32:21:17.4 |
HIP 118304 |
21.26 |
| 2026-08-05 12:00 |
00:01:09.93 |
-32:22:24.6 |
HIP 118304 |
20.50 |
| 2026-08-06 00:00 |
00:01:03.25 |
-32:23:31.7 |
HIP 118304 |
19.86 |
| 2026-08-06 12:00 |
00:00:56.53 |
-32:24:38.7 |
HIP 118304 |
19.36 |
| 2026-08-07 00:00 |
00:00:49.75 |
-32:25:45.6 |
HIP 118304 |
19.01 |
| 2026-08-07 12:00 |
00:00:42.93 |
-32:26:52.4 |
HIP 118304 |
18.82 |
| 2026-08-08 00:00 |
00:00:36.05 |
-32:27:59.1 |
HIP 118304 |
18.80 |
| 2026-08-08 12:00 |
00:00:29.13 |
-32:29:05.6 |
HIP 94 |
18.52 |
| 2026-08-09 00:00 |
00:00:22.17 |
-32:30:12.0 |
HIP 94 |
18.33 |
| 2026-08-09 12:00 |
00:00:15.15 |
-32:31:18.3 |
HIP 94 |
18.33 |
| 2026-08-10 00:00 |
00:00:08.09 |
-32:32:24.4 |
HIP 94 |
18.52 |
| 2026-08-10 12:00 |
00:00:00.98 |
-32:33:30.3 |
HIP 94 |
18.90 |
| 2026-08-11 00:00 |
23:59:53.83 |
-32:34:36.1 |
HIP 94 |
19.47 |
| 2026-08-11 12:00 |
23:59:46.63 |
-32:35:41.8 |
HIP 94 |
20.19 |
| 2026-08-12 00:00 |
23:59:39.39 |
-32:36:47.2 |
HIP 94 |
21.07 |
| 2026-08-12 12:00 |
23:59:32.10 |
-32:37:52.5 |
HIP 94 |
22.08 |
| 2026-08-13 00:00 |
23:59:24.77 |
-32:38:57.6 |
HIP 94 |
23.21 |
| 2026-08-13 12:00 |
23:59:17.39 |
-32:40:02.5 |
HIP 94 |
24.44 |
| 2026-08-14 00:00 |
23:59:09.98 |
-32:41:07.3 |
HIP 94 |
25.76 |
| 2026-08-14 12:00 |
23:59:02.51 |
-32:42:11.8 |
HIP 94 |
27.16 |
| 2026-08-15 00:00 |
23:58:55.01 |
-32:43:16.1 |
HIP 118165 |
26.52 |
| 2026-08-15 12:00 |
23:58:47.47 |
-32:44:20.2 |
HIP 118165 |
24.97 |
| 2026-08-16 00:00 |
23:58:39.88 |
-32:45:24.1 |
HIP 118165 |
23.47 |
| 2026-08-16 12:00 |
23:58:32.25 |
-32:46:27.8 |
HIP 118165 |
22.04 |
| 2026-08-17 00:00 |
23:58:24.59 |
-32:47:31.2 |
HIP 118165 |
20.69 |
| 2026-08-17 12:00 |
23:58:16.88 |
-32:48:34.5 |
HIP 118165 |
19.44 |
| 2026-08-18 00:00 |
23:58:09.14 |
-32:49:37.4 |
HIP 118165 |
18.31 |
| 2026-08-18 12:00 |
23:58:01.36 |
-32:50:40.2 |
HIP 118165 |
17.33 |
| 2026-08-19 00:00 |
23:57:53.53 |
-32:51:42.6 |
HIP 118165 |
16.52 |