P/2021 R8 (Sheppard)

메타데이터

항목
Designation P/2021 R8 (Sheppard)
Type P
Perihelion (tp_cal, UTC) 2021-10-07T12:21:16.145280Z
Orbit solution date (soln_date, UTC) 2021-12-07T11:12:02Z
Obs used 26
NEO -
M1 18.600
K1 10.000
PC -
Discovery observation (MPC, UTC) 2021-09-05T13:08:45.772800Z
Discovery magnitude (MPC) 21.69 G
Discovery observatory (MPC) T09 · Subaru Telescope, Maunakea
Osculating 궤도요소
항목
Epoch (epoch_cal, TDB) 2021-09-16.0000000
e 0.29404210
q (au) 2.130978
a (au) 3.018562
i (deg) 2.203054
Ω (om, deg) 167.025325
ω (w, deg) 190.793883
M (ma, deg) 355.956657

밝기

P/2021 R8 (Sheppard) · Magnitude (Full range)

산란 + 전체 선형

$$ M_a = (16.419 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목
H0 16.419
n 6.000
gf 1.000
gb -0.900
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

찾아보기

P/2021 R8 (Sheppard) · Next 30 Days

천체력

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-06-01 00:00 20:38:22.12 -15:46:41.5 HIP 101999 35.95
2026-06-01 12:00 20:38:32.07 -15:45:47.3 HIP 101999 33.58
2026-06-02 00:00 20:38:41.66 -15:44:54.5 HIP 101999 31.32
2026-06-02 12:00 20:38:50.90 -15:44:03.1 HIP 101999 29.17
2026-06-03 00:00 20:38:59.78 -15:43:13.1 HIP 101999 27.14
2026-06-03 12:00 20:39:08.29 -15:42:24.5 HIP 101999 25.22
2026-06-04 00:00 20:39:16.44 -15:41:37.4 HIP 101999 23.42
2026-06-04 12:00 20:39:24.22 -15:40:51.8 HIP 101999 21.74
2026-06-05 00:00 20:39:31.64 -15:40:07.6 HIP 101999 20.19
2026-06-05 12:00 20:39:38.69 -15:39:24.9 HIP 101999 18.78
2026-06-06 00:00 20:39:45.36 -15:38:43.7 HIP 101999 17.50
2026-06-06 12:00 20:39:51.66 -15:38:04.1 HIP 101999 16.36
2026-06-07 00:00 20:39:57.59 -15:37:26.0 HIP 101999 15.36
2026-06-07 12:00 20:40:03.13 -15:36:49.4 HIP 101999 14.51
2026-06-08 00:00 20:40:08.30 -15:36:14.4 HIP 101999 13.78
2026-06-08 12:00 20:40:13.09 -15:35:41.0 HIP 101999 13.19
2026-06-09 00:00 20:40:17.50 -15:35:09.2 HIP 101999 12.71
2026-06-09 12:00 20:40:21.52 -15:34:39.0 HIP 101999 12.35
2026-06-10 00:00 20:40:25.15 -15:34:10.4 HIP 101999 12.07
2026-06-10 12:00 20:40:28.40 -15:33:43.4 HIP 101999 11.86
2026-06-11 00:00 20:40:31.27 -15:33:18.1 HIP 101999 11.71
2026-06-11 12:00 20:40:33.74 -15:32:54.4 HIP 101999 11.60
2026-06-12 00:00 20:40:35.82 -15:32:32.4 HIP 101999 11.51
2026-06-12 12:00 20:40:37.51 -15:32:12.0 HIP 101999 11.42
2026-06-13 00:00 20:40:38.80 -15:31:53.4 HIP 101999 11.33
2026-06-13 12:00 20:40:39.71 -15:31:36.5 HIP 101999 11.22
2026-06-14 00:00 20:40:40.21 -15:31:21.2 HIP 101999 11.09
2026-06-14 12:00 20:40:40.33 -15:31:07.7 HIP 101999 10.93
2026-06-15 00:00 20:40:40.04 -15:30:55.9 HIP 101999 10.73
2026-06-15 12:00 20:40:39.37 -15:30:45.9 HIP 101999 10.50
2026-06-16 00:00 20:40:38.29 -15:30:37.5 HIP 101999 10.23
2026-06-16 12:00 20:40:36.82 -15:30:30.9 HIP 101999 9.93
2026-06-17 00:00 20:40:34.96 -15:30:26.1 HIP 101999 9.61
2026-06-17 12:00 20:40:32.69 -15:30:23.0 HIP 101999 9.27
2026-06-18 00:00 20:40:30.04 -15:30:21.7 HIP 101999 8.93
2026-06-18 12:00 20:40:26.99 -15:30:22.1 HIP 101999 8.61
2026-06-19 00:00 20:40:23.54 -15:30:24.3 HIP 101999 8.34
2026-06-19 12:00 20:40:19.70 -15:30:28.2 HIP 101999 8.16
2026-06-20 00:00 20:40:15.46 -15:30:33.9 HIP 101999 8.10
2026-06-20 12:00 20:40:10.84 -15:30:41.3 HIP 101999 8.20
2026-06-21 00:00 20:40:05.82 -15:30:50.6 HIP 101999 8.50
2026-06-21 12:00 20:40:00.40 -15:31:01.5 HIP 101999 9.02
2026-06-22 00:00 20:39:54.60 -15:31:14.3 HIP 101999 9.75