| Parameter |
Value |
| Designation |
97P/Metcalf-Brewington |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2022-02-20T14:52:28.525440Z |
| Orbit solution date (soln_date, UTC) |
2024-04-18T00:13:54Z |
| Obs used |
391 |
| NEO |
- |
| M1 |
13.700 |
| K1 |
7.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-04-13.0000000 |
| e |
0.45694184 |
| q (au) |
2.606598 |
| a (au) |
4.799850 |
| i (deg) |
17.860186 |
| Ω (om, deg) |
185.170868 |
| ω (w, deg) |
228.218375 |
| M (ma, deg) |
193.671045 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.502 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.502 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.635 |
| k |
0.800 |
| δ90 |
10.000 |
| Parameter |
Symbol |
Range |
Description |
| Absolute magnitude at 1 AU from Sun and Earth |
H0 |
-5 to 20 |
Intrinsic brightness of the comet |
| Photometric slope parameter |
n |
2 to 6 |
Rate of brightness change with heliocentric distance |
| Forward scattering asymmetry factor |
gf |
0.8 to 1 |
Degree of forward scattering |
| Backward scattering asymmetry factor |
gb |
-1 to -0.5 |
Degree of backward scattering |
| Partitioning coefficient |
k |
0.8 to 1 |
Ratio between forward/backward scattering contributions |
| Dust-to-gas brightness ratio |
δ90 |
1 to 10 |
Relative contribution of dust scattering to gas emission |
Reference: EPSC-DPS2025-160
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
14:37:10.53 |
-04:11:21.8 |
HIP 71462 |
6.79 |
| 2026-09-20 12:00 |
14:37:25.60 |
-04:12:47.5 |
HIP 71462 |
8.83 |
| 2026-09-21 00:00 |
14:37:40.74 |
-04:14:13.3 |
HIP 71462 |
11.95 |
| 2026-09-21 12:00 |
14:37:55.95 |
-04:15:39.1 |
HIP 71462 |
15.51 |
| 2026-09-22 00:00 |
14:38:11.22 |
-04:17:04.9 |
HIP 71462 |
19.28 |
| 2026-09-22 12:00 |
14:38:26.56 |
-04:18:30.7 |
HIP 71462 |
23.17 |
| 2026-09-23 00:00 |
14:38:41.97 |
-04:19:56.4 |
HIP 71462 |
27.13 |
| 2026-09-23 12:00 |
14:38:57.43 |
-04:21:22.1 |
HIP 71462 |
31.14 |
| 2026-09-24 00:00 |
14:39:12.97 |
-04:22:47.8 |
HIP 71462 |
35.19 |
| 2026-09-24 12:00 |
14:39:28.56 |
-04:24:13.5 |
HIP 71462 |
39.27 |
| 2026-09-25 00:00 |
14:39:44.22 |
-04:25:39.1 |
HIP 71803 |
38.56 |
| 2026-09-25 12:00 |
14:39:59.93 |
-04:27:04.7 |
HIP 71803 |
35.16 |
| 2026-09-26 00:00 |
14:40:15.71 |
-04:28:30.3 |
HIP 71803 |
31.94 |
| 2026-09-26 12:00 |
14:40:31.55 |
-04:29:55.8 |
HIP 71803 |
28.96 |
| 2026-09-27 00:00 |
14:40:47.45 |
-04:31:21.2 |
HIP 71803 |
26.31 |
| 2026-09-27 12:00 |
14:41:03.41 |
-04:32:46.6 |
HIP 71803 |
24.10 |
| 2026-09-28 00:00 |
14:41:19.43 |
-04:34:12.0 |
HIP 71879 |
20.94 |
| 2026-09-28 12:00 |
14:41:35.51 |
-04:35:37.3 |
HIP 71879 |
17.60 |
| 2026-09-29 00:00 |
14:41:51.65 |
-04:37:02.5 |
HIP 71879 |
14.74 |
| 2026-09-29 12:00 |
14:42:07.84 |
-04:38:27.6 |
HIP 71879 |
12.69 |
| 2026-09-30 00:00 |
14:42:24.09 |
-04:39:52.7 |
HIP 71879 |
11.90 |
| 2026-09-30 12:00 |
14:42:40.39 |
-04:41:17.7 |
HIP 71879 |
12.61 |
| 2026-10-01 00:00 |
14:42:56.76 |
-04:42:42.6 |
HIP 71879 |
14.63 |
| 2026-10-01 12:00 |
14:43:13.17 |
-04:44:07.4 |
HIP 71879 |
17.51 |
| 2026-10-02 00:00 |
14:43:29.65 |
-04:45:32.1 |
HIP 71879 |
20.91 |
| 2026-10-02 12:00 |
14:43:46.18 |
-04:46:56.8 |
HIP 71879 |
24.62 |
| 2026-10-03 00:00 |
14:44:02.76 |
-04:48:21.3 |
HIP 71879 |
28.53 |
| 2026-10-03 12:00 |
14:44:19.39 |
-04:49:45.8 |
HIP 72049 |
30.59 |
| 2026-10-04 00:00 |
14:44:36.08 |
-04:51:10.1 |
HIP 72049 |
32.41 |
| 2026-10-04 12:00 |
14:44:52.82 |
-04:52:34.3 |
HIP 72188 |
32.39 |
| 2026-10-05 00:00 |
14:45:09.61 |
-04:53:58.4 |
HIP 72188 |
31.92 |
| 2026-10-05 12:00 |
14:45:26.45 |
-04:55:22.4 |
HIP 72188 |
32.04 |
| 2026-10-06 00:00 |
14:45:43.35 |
-04:56:46.2 |
HIP 72188 |
32.76 |
| 2026-10-06 12:00 |
14:46:00.29 |
-04:58:10.0 |
HIP 72188 |
34.05 |
| 2026-10-07 00:00 |
14:46:17.28 |
-04:59:33.6 |
HIP 72188 |
35.85 |
| 2026-10-07 12:00 |
14:46:34.33 |
-05:00:57.0 |
HIP 72388 |
36.69 |
| 2026-10-08 00:00 |
14:46:51.42 |
-05:02:20.3 |
HIP 72388 |
33.14 |
| 2026-10-08 12:00 |
14:47:08.55 |
-05:03:43.5 |
HIP 72388 |
29.84 |
| 2026-10-09 00:00 |
14:47:25.74 |
-05:05:06.5 |
HIP 72388 |
26.87 |
| 2026-10-09 12:00 |
14:47:42.97 |
-05:06:29.3 |
HIP 72388 |
24.38 |
| 2026-10-10 00:00 |
14:48:00.24 |
-05:07:52.0 |
HIP 72388 |
22.53 |
| 2026-10-10 12:00 |
14:48:17.56 |
-05:09:14.5 |
HIP 72388 |
21.49 |
| 2026-10-11 00:00 |
14:48:34.93 |
-05:10:36.8 |
HIP 72388 |
21.39 |