메타데이터
| 항목 |
값 |
| Designation |
C/2018 F1 (Grauer) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2018-12-14T01:55:08.552640Z |
| Orbit solution date (soln_date, UTC) |
2021-09-04T23:42:57Z |
| Obs used |
221 |
| NEO |
- |
| M1 |
12.700 |
| K1 |
6.250 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2018-03-17T08:17:23.424000Z |
| Discovery magnitude (MPC) |
19.10 T |
| Discovery observatory (MPC) |
G96 · University of Arizona Mt. Lemmon Survey |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2019-03-06.0000000 |
| e |
0.99071069 |
| q (au) |
2.993048 |
| a (au) |
322.203595 |
| i (deg) |
46.070619 |
| Ω (om, deg) |
177.285875 |
| ω (w, deg) |
71.628120 |
| M (ma, deg) |
0.013960 |
밝기
산란 + 전체 선형
$$
M_a = (10.042 + 4.054\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
10.042 |
| n |
4.054 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
1.000 |
| δ90 |
1.000 |
| 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 |
| 2017-12-22 |
2018-07-16 |
+4.3609 |
-2.361 |
| 2019-03-22 |
2019-08-08 |
-24.0881 |
+12.948 |
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 |
01:32:44.04 |
-09:00:40.1 |
HIP 7222 |
4.81 |
| 2026-06-01 12:00 |
01:32:48.77 |
-09:00:43.1 |
HIP 7222 |
3.64 |
| 2026-06-02 00:00 |
01:32:53.47 |
-09:00:46.5 |
HIP 7222 |
2.48 |
| 2026-06-02 12:00 |
01:32:58.13 |
-09:00:50.2 |
HIP 7222 |
1.33 |
| 2026-06-03 00:00 |
01:33:02.76 |
-09:00:54.4 |
HIP 7222 |
0.19 |
| 2026-06-03 12:00 |
01:33:07.36 |
-09:00:58.8 |
HIP 7222 |
0.95 |
| 2026-06-04 00:00 |
01:33:11.92 |
-09:01:03.7 |
HIP 7222 |
2.08 |
| 2026-06-04 12:00 |
01:33:16.45 |
-09:01:08.8 |
HIP 7222 |
3.21 |
| 2026-06-05 00:00 |
01:33:20.95 |
-09:01:14.4 |
HIP 7222 |
4.32 |
| 2026-06-05 12:00 |
01:33:25.41 |
-09:01:20.3 |
HIP 7222 |
5.43 |
| 2026-06-06 00:00 |
01:33:29.84 |
-09:01:26.6 |
HIP 7222 |
6.52 |
| 2026-06-06 12:00 |
01:33:34.23 |
-09:01:33.2 |
HIP 7222 |
7.61 |
| 2026-06-07 00:00 |
01:33:38.59 |
-09:01:40.2 |
HIP 7222 |
8.70 |
| 2026-06-07 12:00 |
01:33:42.91 |
-09:01:47.6 |
HIP 7222 |
9.77 |
| 2026-06-08 00:00 |
01:33:47.20 |
-09:01:55.3 |
HIP 7222 |
10.84 |
| 2026-06-08 12:00 |
01:33:51.45 |
-09:02:03.4 |
HIP 7222 |
11.89 |
| 2026-06-09 00:00 |
01:33:55.66 |
-09:02:11.8 |
HIP 7222 |
12.94 |
| 2026-06-09 12:00 |
01:33:59.84 |
-09:02:20.6 |
HIP 7222 |
13.99 |
| 2026-06-10 00:00 |
01:34:03.99 |
-09:02:29.8 |
HIP 7222 |
15.02 |
| 2026-06-10 12:00 |
01:34:08.09 |
-09:02:39.4 |
HIP 7222 |
16.04 |
| 2026-06-11 00:00 |
01:34:12.16 |
-09:02:49.3 |
HIP 7222 |
17.06 |
| 2026-06-11 12:00 |
01:34:16.19 |
-09:02:59.5 |
HIP 7222 |
18.07 |
| 2026-06-12 00:00 |
01:34:20.19 |
-09:03:10.2 |
HIP 7222 |
19.07 |
| 2026-06-12 12:00 |
01:34:24.14 |
-09:03:21.2 |
HIP 7222 |
20.06 |
| 2026-06-13 00:00 |
01:34:28.06 |
-09:03:32.5 |
HIP 7222 |
21.04 |
| 2026-06-13 12:00 |
01:34:31.94 |
-09:03:44.3 |
HIP 7222 |
22.02 |
| 2026-06-14 00:00 |
01:34:35.78 |
-09:03:56.4 |
HIP 7222 |
22.99 |
| 2026-06-14 12:00 |
01:34:39.58 |
-09:04:08.8 |
HIP 7222 |
23.94 |
| 2026-06-15 00:00 |
01:34:43.35 |
-09:04:21.6 |
HIP 7222 |
24.89 |
| 2026-06-15 12:00 |
01:34:47.07 |
-09:04:34.8 |
HIP 7222 |
25.83 |
| 2026-06-16 00:00 |
01:34:50.75 |
-09:04:48.4 |
HIP 7222 |
26.77 |
| 2026-06-16 12:00 |
01:34:54.40 |
-09:05:02.3 |
HIP 7222 |
27.69 |
| 2026-06-17 00:00 |
01:34:58.00 |
-09:05:16.6 |
HIP 7222 |
28.61 |
| 2026-06-17 12:00 |
01:35:01.56 |
-09:05:31.2 |
HIP 7222 |
29.51 |
| 2026-06-18 00:00 |
01:35:05.08 |
-09:05:46.3 |
HIP 7222 |
30.41 |
| 2026-06-18 12:00 |
01:35:08.57 |
-09:06:01.6 |
HIP 7222 |
31.30 |
| 2026-06-19 00:00 |
01:35:12.01 |
-09:06:17.4 |
HIP 7222 |
32.18 |
| 2026-06-19 12:00 |
01:35:15.41 |
-09:06:33.4 |
HIP 7222 |
33.05 |
| 2026-06-20 00:00 |
01:35:18.76 |
-09:06:49.9 |
HIP 7222 |
33.92 |
| 2026-06-20 12:00 |
01:35:22.08 |
-09:07:06.7 |
HIP 7222 |
34.77 |
| 2026-06-21 00:00 |
01:35:25.36 |
-09:07:23.9 |
HIP 7222 |
35.62 |
| 2026-06-21 12:00 |
01:35:28.59 |
-09:07:41.4 |
HIP 7580 |
35.87 |
| 2026-06-22 00:00 |
01:35:31.78 |
-09:07:59.3 |
HIP 7580 |
35.03 |