| 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) |
| 2026-06-01 00:00 |
14:24:37.06 |
-01:32:46.5 |
HIP 70285 |
27.03 |
| 2026-06-01 12:00 |
14:24:26.98 |
-01:32:08.0 |
HIP 70285 |
24.56 |
| 2026-06-02 00:00 |
14:24:16.99 |
-01:31:30.5 |
HIP 70285 |
22.15 |
| 2026-06-02 12:00 |
14:24:07.11 |
-01:30:53.9 |
HIP 70285 |
19.80 |
| 2026-06-03 00:00 |
14:23:57.33 |
-01:30:18.2 |
HIP 70285 |
17.52 |
| 2026-06-03 12:00 |
14:23:47.66 |
-01:29:43.5 |
HIP 70285 |
15.34 |
| 2026-06-04 00:00 |
14:23:38.08 |
-01:29:09.7 |
HIP 70285 |
13.28 |
| 2026-06-04 12:00 |
14:23:28.62 |
-01:28:36.9 |
HIP 70285 |
11.40 |
| 2026-06-05 00:00 |
14:23:19.26 |
-01:28:05.0 |
HIP 70285 |
9.77 |
| 2026-06-05 12:00 |
14:23:10.00 |
-01:27:34.1 |
HIP 70285 |
8.52 |
| 2026-06-06 00:00 |
14:23:00.86 |
-01:27:04.1 |
HIP 70285 |
7.80 |
| 2026-06-06 12:00 |
14:22:51.82 |
-01:26:35.0 |
HIP 70285 |
7.74 |
| 2026-06-07 00:00 |
14:22:42.89 |
-01:26:06.9 |
HIP 70285 |
8.32 |
| 2026-06-07 12:00 |
14:22:34.08 |
-01:25:39.7 |
HIP 70285 |
9.41 |
| 2026-06-08 00:00 |
14:22:25.37 |
-01:25:13.5 |
HIP 70285 |
10.83 |
| 2026-06-08 12:00 |
14:22:16.78 |
-01:24:48.2 |
HIP 70285 |
12.46 |
| 2026-06-09 00:00 |
14:22:08.30 |
-01:24:23.9 |
HIP 70285 |
14.20 |
| 2026-06-09 12:00 |
14:21:59.94 |
-01:24:00.5 |
HIP 70285 |
16.02 |
| 2026-06-10 00:00 |
14:21:51.69 |
-01:23:38.1 |
HIP 70285 |
17.87 |
| 2026-06-10 12:00 |
14:21:43.56 |
-01:23:16.6 |
HIP 70285 |
19.73 |
| 2026-06-11 00:00 |
14:21:35.55 |
-01:22:56.1 |
HIP 70106 |
19.82 |
| 2026-06-11 12:00 |
14:21:27.65 |
-01:22:36.5 |
HIP 70106 |
18.86 |
| 2026-06-12 00:00 |
14:21:19.88 |
-01:22:17.9 |
HIP 70106 |
18.08 |
| 2026-06-12 12:00 |
14:21:12.22 |
-01:22:00.2 |
HIP 70106 |
17.47 |
| 2026-06-13 00:00 |
14:21:04.69 |
-01:21:43.5 |
HIP 70106 |
17.06 |
| 2026-06-13 12:00 |
14:20:57.27 |
-01:21:27.8 |
HIP 70106 |
16.85 |
| 2026-06-14 00:00 |
14:20:49.98 |
-01:21:12.9 |
HIP 70106 |
16.83 |
| 2026-06-14 12:00 |
14:20:42.81 |
-01:20:59.1 |
HIP 70106 |
16.99 |
| 2026-06-15 00:00 |
14:20:35.77 |
-01:20:46.2 |
HIP 70106 |
17.32 |
| 2026-06-15 12:00 |
14:20:28.85 |
-01:20:34.2 |
HIP 70106 |
17.80 |
| 2026-06-16 00:00 |
14:20:22.05 |
-01:20:23.2 |
HIP 70106 |
18.41 |
| 2026-06-16 12:00 |
14:20:15.38 |
-01:20:13.1 |
HIP 70106 |
19.13 |
| 2026-06-17 00:00 |
14:20:08.84 |
-01:20:04.0 |
HIP 70106 |
19.93 |
| 2026-06-17 12:00 |
14:20:02.43 |
-01:19:55.8 |
HIP 70106 |
20.81 |
| 2026-06-18 00:00 |
14:19:56.14 |
-01:19:48.5 |
HIP 70106 |
21.73 |
| 2026-06-18 12:00 |
14:19:49.98 |
-01:19:42.2 |
HIP 70106 |
22.70 |
| 2026-06-19 00:00 |
14:19:43.95 |
-01:19:36.8 |
HIP 70106 |
23.69 |
| 2026-06-19 12:00 |
14:19:38.05 |
-01:19:32.3 |
HIP 70106 |
24.71 |
| 2026-06-20 00:00 |
14:19:32.28 |
-01:19:28.8 |
HIP 70106 |
25.73 |
| 2026-06-20 12:00 |
14:19:26.64 |
-01:19:26.1 |
HIP 70106 |
26.76 |
| 2026-06-21 00:00 |
14:19:21.13 |
-01:19:24.4 |
HIP 69866 |
27.03 |
| 2026-06-21 12:00 |
14:19:15.76 |
-01:19:23.7 |
HIP 69866 |
25.90 |
| 2026-06-22 00:00 |
14:19:10.51 |
-01:19:23.8 |
HIP 69866 |
24.83 |