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) |
| 2026-06-01 00:00 |
06:33:51.05 |
+18:57:21.6 |
HIP 31261 |
11.88 |
| 2026-06-01 12:00 |
06:33:55.90 |
+18:57:19.6 |
HIP 31261 |
12.52 |
| 2026-06-02 00:00 |
06:34:00.76 |
+18:57:17.6 |
HIP 31261 |
13.24 |
| 2026-06-02 12:00 |
06:34:05.63 |
+18:57:15.6 |
HIP 31261 |
14.01 |
| 2026-06-03 00:00 |
06:34:10.53 |
+18:57:13.4 |
HIP 31261 |
14.84 |
| 2026-06-03 12:00 |
06:34:15.44 |
+18:57:11.2 |
HIP 31261 |
15.71 |
| 2026-06-04 00:00 |
06:34:20.36 |
+18:57:09.0 |
HIP 31261 |
16.62 |
| 2026-06-04 12:00 |
06:34:25.31 |
+18:57:06.7 |
HIP 31261 |
17.56 |
| 2026-06-05 00:00 |
06:34:30.26 |
+18:57:04.3 |
HIP 31261 |
18.54 |
| 2026-06-05 12:00 |
06:34:35.24 |
+18:57:01.8 |
HIP 31261 |
19.53 |
| 2026-06-06 00:00 |
06:34:40.22 |
+18:56:59.3 |
HIP 31261 |
20.55 |
| 2026-06-06 12:00 |
06:34:45.22 |
+18:56:56.7 |
HIP 31261 |
21.59 |
| 2026-06-07 00:00 |
06:34:50.24 |
+18:56:54.1 |
HIP 31261 |
22.64 |
| 2026-06-07 12:00 |
06:34:55.27 |
+18:56:51.4 |
HIP 31261 |
23.71 |
| 2026-06-08 00:00 |
06:35:00.31 |
+18:56:48.6 |
HIP 31261 |
24.79 |
| 2026-06-08 12:00 |
06:35:05.37 |
+18:56:45.8 |
HIP 31261 |
25.89 |
| 2026-06-09 00:00 |
06:35:10.44 |
+18:56:42.9 |
HIP 31261 |
26.99 |
| 2026-06-09 12:00 |
06:35:15.52 |
+18:56:40.0 |
HIP 31261 |
28.11 |
| 2026-06-10 00:00 |
06:35:20.62 |
+18:56:37.0 |
HIP 31618 |
27.26 |
| 2026-06-10 12:00 |
06:35:25.72 |
+18:56:33.9 |
HIP 31618 |
26.23 |
| 2026-06-11 00:00 |
06:35:30.84 |
+18:56:30.7 |
HIP 31618 |
25.22 |
| 2026-06-11 12:00 |
06:35:35.97 |
+18:56:27.5 |
HIP 31618 |
24.22 |
| 2026-06-12 00:00 |
06:35:41.11 |
+18:56:24.3 |
HIP 31618 |
23.24 |
| 2026-06-12 12:00 |
06:35:46.27 |
+18:56:20.9 |
HIP 31618 |
22.28 |
| 2026-06-13 00:00 |
06:35:51.43 |
+18:56:17.6 |
HIP 31618 |
21.35 |
| 2026-06-13 12:00 |
06:35:56.60 |
+18:56:14.1 |
HIP 31618 |
20.44 |
| 2026-06-14 00:00 |
06:36:01.79 |
+18:56:10.6 |
HIP 31618 |
19.57 |
| 2026-06-14 12:00 |
06:36:06.98 |
+18:56:07.0 |
HIP 31618 |
18.74 |
| 2026-06-15 00:00 |
06:36:12.18 |
+18:56:03.4 |
HIP 31618 |
17.96 |
| 2026-06-15 12:00 |
06:36:17.39 |
+18:55:59.7 |
HIP 31618 |
17.22 |
| 2026-06-16 00:00 |
06:36:22.61 |
+18:55:55.9 |
HIP 31618 |
16.55 |
| 2026-06-16 12:00 |
06:36:27.84 |
+18:55:52.1 |
HIP 31618 |
15.94 |
| 2026-06-17 00:00 |
06:36:33.08 |
+18:55:48.2 |
HIP 31618 |
15.41 |
| 2026-06-17 12:00 |
06:36:38.32 |
+18:55:44.3 |
HIP 31618 |
14.96 |
| 2026-06-18 00:00 |
06:36:43.57 |
+18:55:40.3 |
HIP 31618 |
14.61 |
| 2026-06-18 12:00 |
06:36:48.83 |
+18:55:36.2 |
HIP 31618 |
14.35 |
| 2026-06-19 00:00 |
06:36:54.09 |
+18:55:32.1 |
HIP 31618 |
14.20 |
| 2026-06-19 12:00 |
06:36:59.36 |
+18:55:27.9 |
HIP 31618 |
14.16 |
| 2026-06-20 00:00 |
06:37:04.64 |
+18:55:23.7 |
HIP 31618 |
14.23 |
| 2026-06-20 12:00 |
06:37:09.92 |
+18:55:19.4 |
HIP 31618 |
14.41 |
| 2026-06-21 00:00 |
06:37:15.21 |
+18:55:15.0 |
HIP 31618 |
14.70 |
| 2026-06-21 12:00 |
06:37:20.50 |
+18:55:10.6 |
HIP 31618 |
15.08 |
| 2026-06-22 00:00 |
06:37:25.79 |
+18:55:06.1 |
HIP 31618 |
15.56 |