메타데이터
| 항목 |
값 |
| Designation |
C/2015 ER61 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-05-09T22:39:09.815040Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:07Z |
| Obs used |
2826 |
| NEO |
- |
| M1 |
10.700 |
| K1 |
5.750 |
| PC |
- |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2017-04-30.0000000 |
| e |
0.99727861 |
| q (au) |
1.042132 |
| a (au) |
382.940360 |
| i (deg) |
6.348649 |
| Ω (om, deg) |
235.221741 |
| ω (w, deg) |
68.192259 |
| M (ma, deg) |
359.998692 |
밝기
산란 + 전체 선형
$$
M_a = (6.321 + 4.711\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
6.321 |
| n |
4.711 |
| gf |
0.988 |
| gb |
-0.804 |
| k |
0.997 |
| δ90 |
9.892 |
| 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 |
| 2016-02-04 |
2017-05-08 |
-1.6785 |
-0.086 |
| 2017-05-13 |
2018-02-24 |
-0.6070 |
+0.658 |
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 |
06:49:44.51 |
+18:32:33.1 |
HIP 32797 |
16.85 |
| 2026-09-20 12:00 |
06:49:45.97 |
+18:32:25.5 |
HIP 32797 |
16.82 |
| 2026-09-21 00:00 |
06:49:47.39 |
+18:32:17.9 |
HIP 32797 |
16.81 |
| 2026-09-21 12:00 |
06:49:48.76 |
+18:32:10.4 |
HIP 32797 |
16.81 |
| 2026-09-22 00:00 |
06:49:50.09 |
+18:32:02.9 |
HIP 32797 |
16.82 |
| 2026-09-22 12:00 |
06:49:51.38 |
+18:31:55.4 |
HIP 32797 |
16.83 |
| 2026-09-23 00:00 |
06:49:52.63 |
+18:31:48.0 |
HIP 32797 |
16.86 |
| 2026-09-23 12:00 |
06:49:53.84 |
+18:31:40.6 |
HIP 32797 |
16.89 |
| 2026-09-24 00:00 |
06:49:55.00 |
+18:31:33.3 |
HIP 32797 |
16.94 |
| 2026-09-24 12:00 |
06:49:56.12 |
+18:31:26.0 |
HIP 32797 |
16.99 |
| 2026-09-25 00:00 |
06:49:57.20 |
+18:31:18.7 |
HIP 32797 |
17.04 |
| 2026-09-25 12:00 |
06:49:58.23 |
+18:31:11.5 |
HIP 32797 |
17.10 |
| 2026-09-26 00:00 |
06:49:59.22 |
+18:31:04.3 |
HIP 32797 |
17.17 |
| 2026-09-26 12:00 |
06:50:00.17 |
+18:30:57.1 |
HIP 32797 |
17.24 |
| 2026-09-27 00:00 |
06:50:01.07 |
+18:30:50.0 |
HIP 32797 |
17.32 |
| 2026-09-27 12:00 |
06:50:01.94 |
+18:30:43.0 |
HIP 32797 |
17.40 |
| 2026-09-28 00:00 |
06:50:02.75 |
+18:30:36.0 |
HIP 32797 |
17.49 |
| 2026-09-28 12:00 |
06:50:03.53 |
+18:30:29.0 |
HIP 32797 |
17.57 |
| 2026-09-29 00:00 |
06:50:04.26 |
+18:30:22.1 |
HIP 32797 |
17.66 |
| 2026-09-29 12:00 |
06:50:04.95 |
+18:30:15.2 |
HIP 32797 |
17.76 |
| 2026-09-30 00:00 |
06:50:05.59 |
+18:30:08.4 |
HIP 32797 |
17.85 |
| 2026-09-30 12:00 |
06:50:06.19 |
+18:30:01.6 |
HIP 32797 |
17.95 |
| 2026-10-01 00:00 |
06:50:06.75 |
+18:29:54.8 |
HIP 32797 |
18.05 |
| 2026-10-01 12:00 |
06:50:07.26 |
+18:29:48.1 |
HIP 32797 |
18.15 |
| 2026-10-02 00:00 |
06:50:07.73 |
+18:29:41.5 |
HIP 32797 |
18.25 |
| 2026-10-02 12:00 |
06:50:08.16 |
+18:29:34.9 |
HIP 32797 |
18.35 |
| 2026-10-03 00:00 |
06:50:08.54 |
+18:29:28.3 |
HIP 32797 |
18.45 |
| 2026-10-03 12:00 |
06:50:08.87 |
+18:29:21.8 |
HIP 32797 |
18.56 |
| 2026-10-04 00:00 |
06:50:09.16 |
+18:29:15.4 |
HIP 32797 |
18.66 |
| 2026-10-04 12:00 |
06:50:09.41 |
+18:29:09.0 |
HIP 32797 |
18.76 |
| 2026-10-05 00:00 |
06:50:09.61 |
+18:29:02.6 |
HIP 32797 |
18.87 |
| 2026-10-05 12:00 |
06:50:09.77 |
+18:28:56.3 |
HIP 32797 |
18.97 |
| 2026-10-06 00:00 |
06:50:09.88 |
+18:28:50.1 |
HIP 32797 |
19.07 |
| 2026-10-06 12:00 |
06:50:09.95 |
+18:28:43.9 |
HIP 32797 |
19.17 |
| 2026-10-07 00:00 |
06:50:09.98 |
+18:28:37.7 |
HIP 32797 |
19.28 |
| 2026-10-07 12:00 |
06:50:09.95 |
+18:28:31.6 |
HIP 32797 |
19.38 |
| 2026-10-08 00:00 |
06:50:09.89 |
+18:28:25.6 |
HIP 32797 |
19.48 |
| 2026-10-08 12:00 |
06:50:09.78 |
+18:28:19.6 |
HIP 32797 |
19.58 |
| 2026-10-09 00:00 |
06:50:09.62 |
+18:28:13.7 |
HIP 32797 |
19.68 |
| 2026-10-09 12:00 |
06:50:09.42 |
+18:28:07.8 |
HIP 32797 |
19.78 |
| 2026-10-10 00:00 |
06:50:09.17 |
+18:28:02.0 |
HIP 32797 |
19.88 |
| 2026-10-10 12:00 |
06:50:08.88 |
+18:27:56.3 |
HIP 32797 |
19.98 |
| 2026-10-11 00:00 |
06:50:08.54 |
+18:27:50.6 |
HIP 32797 |
20.08 |