C/2015 X7 (ATLAS)

메타데이터

항목
Designation C/2015 X7 (ATLAS)
Type C
Perihelion (tp_cal, UTC) 2016-07-30T05:59:33.682560Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:33:20Z
Obs used 620
NEO -
M1 11.600
K1 6.000
PC -
Osculating 궤도요소
항목
Epoch (epoch_cal, TDB) 2016-09-22.0000000
e 1.00189036
q (au) 3.684550
a (au) -1949.127032
i (deg) 57.578925
Ω (om, deg) 139.884070
ω (w, deg) 348.488537
M (ma, deg) 0.000616

밝기

C/2015 X7 (ATLAS) · Magnitude (Full range)

산란 + 전체 선형

$$ M_a = (11.078 + 2.092\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목
H0 11.078
n 2.092
gf 1.000
gb -0.502
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
2015-01-28 2016-05-01 -0.2726 -0.309
2016-11-02 2017-06-16 -0.5340 +0.555

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 18:28:56.63 +24:52:32.0 HIP 90483 19.29
2026-06-01 12:00 18:28:51.98 +24:52:49.9 HIP 90483 18.59
2026-06-02 00:00 18:28:47.31 +24:53:07.3 HIP 90483 17.93
2026-06-02 12:00 18:28:42.61 +24:53:24.2 HIP 90483 17.30
2026-06-03 00:00 18:28:37.89 +24:53:40.7 HIP 90483 16.71
2026-06-03 12:00 18:28:33.15 +24:53:56.6 HIP 90483 16.17
2026-06-04 00:00 18:28:28.39 +24:54:12.2 HIP 90483 15.68
2026-06-04 12:00 18:28:23.62 +24:54:27.2 HIP 90483 15.24
2026-06-05 00:00 18:28:18.82 +24:54:41.8 HIP 90483 14.87
2026-06-05 12:00 18:28:14.00 +24:54:55.8 HIP 90483 14.56
2026-06-06 00:00 18:28:09.16 +24:55:09.4 HIP 90483 14.32
2026-06-06 12:00 18:28:04.31 +24:55:22.6 HIP 90483 14.16
2026-06-07 00:00 18:27:59.43 +24:55:35.2 HIP 90483 14.08
2026-06-07 12:00 18:27:54.54 +24:55:47.4 HIP 90483 14.08
2026-06-08 00:00 18:27:49.63 +24:55:59.0 HIP 90483 14.17
2026-06-08 12:00 18:27:44.71 +24:56:10.2 HIP 90483 14.33
2026-06-09 00:00 18:27:39.76 +24:56:20.9 HIP 90483 14.57
2026-06-09 12:00 18:27:34.80 +24:56:31.1 HIP 90483 14.89
2026-06-10 00:00 18:27:29.83 +24:56:40.8 HIP 90483 15.28
2026-06-10 12:00 18:27:24.84 +24:56:50.0 HIP 90483 15.73
2026-06-11 00:00 18:27:19.84 +24:56:58.8 HIP 90483 16.25
2026-06-11 12:00 18:27:14.82 +24:57:07.0 HIP 90483 16.82
2026-06-12 00:00 18:27:09.79 +24:57:14.7 HIP 90483 17.45
2026-06-12 12:00 18:27:04.74 +24:57:21.9 HIP 90483 18.11
2026-06-13 00:00 18:26:59.68 +24:57:28.7 HIP 90483 18.82
2026-06-13 12:00 18:26:54.61 +24:57:34.9 HIP 90483 19.57
2026-06-14 00:00 18:26:49.53 +24:57:40.6 HIP 90483 20.35
2026-06-14 12:00 18:26:44.43 +24:57:45.8 HIP 90483 21.16
2026-06-15 00:00 18:26:39.33 +24:57:50.5 HIP 90483 22.00
2026-06-15 12:00 18:26:34.21 +24:57:54.7 HIP 90483 22.86
2026-06-16 00:00 18:26:29.09 +24:57:58.4 HIP 90483 23.75
2026-06-16 12:00 18:26:23.95 +24:58:01.6 HIP 90483 24.65
2026-06-17 00:00 18:26:18.81 +24:58:04.3 HIP 90483 25.57
2026-06-17 12:00 18:26:13.65 +24:58:06.4 HIP 90265 25.35
2026-06-18 00:00 18:26:08.49 +24:58:08.1 HIP 90265 24.67
2026-06-18 12:00 18:26:03.33 +24:58:09.2 HIP 90265 24.02
2026-06-19 00:00 18:25:58.15 +24:58:09.9 HIP 90265 23.40
2026-06-19 12:00 18:25:52.97 +24:58:10.0 HIP 90265 22.81
2026-06-20 00:00 18:25:47.78 +24:58:09.6 HIP 90265 22.27
2026-06-20 12:00 18:25:42.59 +24:58:08.7 HIP 90265 21.76
2026-06-21 00:00 18:25:37.39 +24:58:07.3 HIP 90265 21.30
2026-06-21 12:00 18:25:32.18 +24:58:05.4 HIP 90265 20.89
2026-06-22 00:00 18:25:26.98 +24:58:03.0 HIP 90265 20.53