메타데이터
| 항목 |
값 |
| Designation |
C/1974 C1 (Bradfield) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1974-03-18T08:33:10.964160Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:22Z |
| Obs used |
173 |
| NEO |
- |
| M1 |
8.600 |
| K1 |
10.000 |
| PC |
- |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
1974-04-20.0000000 |
| e |
0.99973403 |
| q (au) |
0.503190 |
| a (au) |
1891.926449 |
| i (deg) |
61.284581 |
| Ω (om, deg) |
143.733056 |
| ω (w, deg) |
333.133285 |
| M (ma, deg) |
0.000391 |
밝기
산란 + 전체 선형
$$
M_a = (7.576 + 2.404\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
7.576 |
| n |
2.404 |
| gf |
1.000 |
| gb |
-0.500 |
| k |
0.989 |
| 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 |
| 1974-02-14 |
1974-03-18 |
-1.9064 |
-0.077 |
| 1974-03-18 |
1974-04-08 |
-3.6784 |
-0.875 |
| 1974-04-08 |
1974-05-07 |
+1.3780 |
+0.127 |
| 1974-05-07 |
1974-06-13 |
-1.2851 |
+0.024 |
| 1974-06-13 |
1974-09-15 |
+11.1441 |
-3.135 |
log10 r = log10(태양거리/AU), Δ = 지구거리(AU)
천체력
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
20:01:19.31 |
+11:17:41.5 |
HIP 98508 |
17.94 |
| 2026-05-12 12:00 |
20:01:18.75 |
+11:17:50.9 |
HIP 98508 |
18.01 |
| 2026-05-13 00:00 |
20:01:18.18 |
+11:18:00.2 |
HIP 98508 |
18.08 |
| 2026-05-13 12:00 |
20:01:17.60 |
+11:18:09.5 |
HIP 98508 |
18.16 |
| 2026-05-14 00:00 |
20:01:17.00 |
+11:18:18.7 |
HIP 98508 |
18.23 |
| 2026-05-14 12:00 |
20:01:16.40 |
+11:18:27.8 |
HIP 98508 |
18.30 |
| 2026-05-15 00:00 |
20:01:15.78 |
+11:18:36.9 |
HIP 98508 |
18.37 |
| 2026-05-15 12:00 |
20:01:15.15 |
+11:18:45.9 |
HIP 98508 |
18.45 |
| 2026-05-16 00:00 |
20:01:14.50 |
+11:18:54.8 |
HIP 98508 |
18.52 |
| 2026-05-16 12:00 |
20:01:13.85 |
+11:19:03.6 |
HIP 98508 |
18.59 |
| 2026-05-17 00:00 |
20:01:13.18 |
+11:19:12.4 |
HIP 98508 |
18.67 |
| 2026-05-17 12:00 |
20:01:12.50 |
+11:19:21.1 |
HIP 98508 |
18.74 |
| 2026-05-18 00:00 |
20:01:11.82 |
+11:19:29.7 |
HIP 98508 |
18.81 |
| 2026-05-18 12:00 |
20:01:11.11 |
+11:19:38.2 |
HIP 98508 |
18.88 |
| 2026-05-19 00:00 |
20:01:10.40 |
+11:19:46.7 |
HIP 98508 |
18.96 |
| 2026-05-19 12:00 |
20:01:09.68 |
+11:19:55.0 |
HIP 98508 |
19.03 |
| 2026-05-20 00:00 |
20:01:08.94 |
+11:20:03.3 |
HIP 98508 |
19.10 |
| 2026-05-20 12:00 |
20:01:08.20 |
+11:20:11.5 |
HIP 98508 |
19.18 |
| 2026-05-21 00:00 |
20:01:07.44 |
+11:20:19.7 |
HIP 98508 |
19.25 |
| 2026-05-21 12:00 |
20:01:06.67 |
+11:20:27.7 |
HIP 98508 |
19.33 |
| 2026-05-22 00:00 |
20:01:05.89 |
+11:20:35.7 |
HIP 98508 |
19.40 |
| 2026-05-22 12:00 |
20:01:05.10 |
+11:20:43.6 |
HIP 98508 |
19.48 |
| 2026-05-23 00:00 |
20:01:04.30 |
+11:20:51.4 |
HIP 98508 |
19.55 |
| 2026-05-23 12:00 |
20:01:03.49 |
+11:20:59.1 |
HIP 98508 |
19.63 |
| 2026-05-24 00:00 |
20:01:02.67 |
+11:21:06.8 |
HIP 98508 |
19.71 |
| 2026-05-24 12:00 |
20:01:01.84 |
+11:21:14.3 |
HIP 98508 |
19.79 |
| 2026-05-25 00:00 |
20:01:00.99 |
+11:21:21.8 |
HIP 98508 |
19.86 |
| 2026-05-25 12:00 |
20:01:00.14 |
+11:21:29.2 |
HIP 98508 |
19.94 |
| 2026-05-26 00:00 |
20:00:59.27 |
+11:21:36.5 |
HIP 98508 |
20.02 |
| 2026-05-26 12:00 |
20:00:58.40 |
+11:21:43.7 |
HIP 98508 |
20.10 |
| 2026-05-27 00:00 |
20:00:57.51 |
+11:21:50.8 |
HIP 98508 |
20.19 |
| 2026-05-27 12:00 |
20:00:56.62 |
+11:21:57.9 |
HIP 98508 |
20.27 |
| 2026-05-28 00:00 |
20:00:55.71 |
+11:22:04.8 |
HIP 98508 |
20.35 |
| 2026-05-28 12:00 |
20:00:54.79 |
+11:22:11.7 |
HIP 98508 |
20.44 |
| 2026-05-29 00:00 |
20:00:53.87 |
+11:22:18.5 |
HIP 98508 |
20.52 |
| 2026-05-29 12:00 |
20:00:52.93 |
+11:22:25.2 |
HIP 98508 |
20.61 |
| 2026-05-30 00:00 |
20:00:51.98 |
+11:22:31.8 |
HIP 98508 |
20.70 |
| 2026-05-30 12:00 |
20:00:51.03 |
+11:22:38.3 |
HIP 98508 |
20.79 |
| 2026-05-31 00:00 |
20:00:50.06 |
+11:22:44.7 |
HIP 98508 |
20.88 |
| 2026-05-31 12:00 |
20:00:49.09 |
+11:22:51.0 |
HIP 98508 |
20.97 |
| 2026-06-01 00:00 |
20:00:48.10 |
+11:22:57.3 |
HIP 98508 |
21.06 |
| 2026-06-01 12:00 |
20:00:47.11 |
+11:23:03.4 |
HIP 98508 |
21.15 |
| 2026-06-02 00:00 |
20:00:46.10 |
+11:23:09.5 |
HIP 98508 |
21.25 |