| 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) |
| 2026-03-26 00:00 |
14:51:35.34 |
-04:39:06.0 |
HIP 72720 |
9.52 |
| 2026-03-26 12:00 |
14:51:26.46 |
-04:37:25.8 |
HIP 72720 |
12.29 |
| 2026-03-27 00:00 |
14:51:17.47 |
-04:35:45.4 |
HIP 72720 |
15.08 |
| 2026-03-27 12:00 |
14:51:08.36 |
-04:34:04.7 |
HIP 72720 |
17.91 |
| 2026-03-28 00:00 |
14:50:59.13 |
-04:32:23.9 |
HIP 72720 |
20.75 |
| 2026-03-28 12:00 |
14:50:49.79 |
-04:30:42.9 |
HIP 72618 |
22.71 |
| 2026-03-29 00:00 |
14:50:40.34 |
-04:29:01.8 |
HIP 72618 |
21.21 |
| 2026-03-29 12:00 |
14:50:30.77 |
-04:27:20.4 |
HIP 72618 |
20.02 |
| 2026-03-30 00:00 |
14:50:21.10 |
-04:25:38.9 |
HIP 72474 |
18.46 |
| 2026-03-30 12:00 |
14:50:11.32 |
-04:23:57.3 |
HIP 72474 |
16.66 |
| 2026-03-31 00:00 |
14:50:01.43 |
-04:22:15.5 |
HIP 72474 |
15.20 |
| 2026-03-31 12:00 |
14:49:51.43 |
-04:20:33.6 |
HIP 72474 |
14.21 |
| 2026-04-01 00:00 |
14:49:41.33 |
-04:18:51.6 |
HIP 72474 |
13.81 |
| 2026-04-01 12:00 |
14:49:31.13 |
-04:17:09.5 |
HIP 72474 |
14.06 |
| 2026-04-02 00:00 |
14:49:20.82 |
-04:15:27.3 |
HIP 72474 |
14.95 |
| 2026-04-02 12:00 |
14:49:10.41 |
-04:13:45.0 |
HIP 72474 |
16.37 |
| 2026-04-03 00:00 |
14:48:59.90 |
-04:12:02.6 |
HIP 72474 |
18.22 |
| 2026-04-03 12:00 |
14:48:49.29 |
-04:10:20.2 |
HIP 72474 |
20.40 |
| 2026-04-04 00:00 |
14:48:38.59 |
-04:08:37.8 |
HIP 72346 |
18.14 |
| 2026-04-04 12:00 |
14:48:27.79 |
-04:06:55.2 |
HIP 72346 |
14.95 |
| 2026-04-05 00:00 |
14:48:16.90 |
-04:05:12.7 |
HIP 72346 |
11.74 |
| 2026-04-05 12:00 |
14:48:05.91 |
-04:03:30.1 |
HIP 72346 |
8.52 |
| 2026-04-06 00:00 |
14:47:54.83 |
-04:01:47.5 |
HIP 72346 |
5.29 |
| 2026-04-06 12:00 |
14:47:43.66 |
-04:00:05.0 |
HIP 72346 |
2.11 |
| 2026-04-07 00:00 |
14:47:32.40 |
-03:58:22.4 |
HIP 72346 |
1.51 |
| 2026-04-07 12:00 |
14:47:21.06 |
-03:56:39.9 |
HIP 72346 |
4.68 |
| 2026-04-08 00:00 |
14:47:09.63 |
-03:54:57.4 |
HIP 72346 |
7.98 |
| 2026-04-08 12:00 |
14:46:58.11 |
-03:53:14.9 |
HIP 72346 |
11.32 |
| 2026-04-09 00:00 |
14:46:46.51 |
-03:51:32.5 |
HIP 72346 |
14.67 |
| 2026-04-09 12:00 |
14:46:34.83 |
-03:49:50.2 |
HIP 72346 |
18.04 |
| 2026-04-10 00:00 |
14:46:23.08 |
-03:48:08.0 |
HIP 72346 |
21.44 |
| 2026-04-10 12:00 |
14:46:11.24 |
-03:46:25.8 |
HIP 72346 |
24.84 |
| 2026-04-11 00:00 |
14:45:59.33 |
-03:44:43.8 |
HIP 72346 |
28.27 |
| 2026-04-11 12:00 |
14:45:47.34 |
-03:43:01.8 |
HIP 72069 |
28.58 |
| 2026-04-12 00:00 |
14:45:35.28 |
-03:41:20.0 |
HIP 72069 |
25.33 |
| 2026-04-12 12:00 |
14:45:23.14 |
-03:39:38.4 |
HIP 72069 |
22.13 |
| 2026-04-13 00:00 |
14:45:10.94 |
-03:37:56.8 |
HIP 72069 |
19.02 |
| 2026-04-13 12:00 |
14:44:58.67 |
-03:36:15.5 |
HIP 72069 |
16.06 |
| 2026-04-14 00:00 |
14:44:46.34 |
-03:34:34.3 |
HIP 72069 |
13.36 |
| 2026-04-14 12:00 |
14:44:33.94 |
-03:32:53.3 |
HIP 72069 |
11.12 |
| 2026-04-15 00:00 |
14:44:21.47 |
-03:31:12.5 |
HIP 72069 |
9.68 |
| 2026-04-15 12:00 |
14:44:08.95 |
-03:29:32.0 |
HIP 72069 |
9.44 |
| 2026-04-16 00:00 |
14:43:56.36 |
-03:27:51.6 |
HIP 72069 |
10.48 |