154P/Brewington
| Parameter |
Value |
| Designation |
154P/Brewington |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2013-12-12T20:02:35.404800Z |
| Orbit solution date (soln_date, UTC) |
2025-04-11T15:12:51Z |
| Obs used |
2636 |
| NEO |
- |
| M1 |
11.400 |
| K1 |
15.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-04-27.0000000 |
| e |
0.67197880 |
| q (au) |
1.601379 |
| a (au) |
4.881937 |
| i (deg) |
17.885394 |
| Ω (om, deg) |
343.428377 |
| ω (w, deg) |
48.913742 |
| M (ma, deg) |
45.701350 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.532 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.532 |
| n |
6.000 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
0.861 |
| δ90 |
1.000 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2024-05-25 |
2024-09-11 |
+15.5682 |
-4.776 |
| 2024-09-11 |
2025-03-06 |
+1.5224 |
-0.666 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
11:35:43.63 |
+01:03:48.4 |
HIP 56605 |
29.46 |
| 2026-02-03 12:00 |
11:35:29.54 |
+01:04:29.4 |
HIP 56605 |
31.36 |
| 2026-02-04 00:00 |
11:35:15.29 |
+01:05:11.5 |
HIP 56377 |
32.70 |
| 2026-02-04 12:00 |
11:35:00.88 |
+01:05:54.7 |
HIP 56377 |
30.10 |
| 2026-02-05 00:00 |
11:34:46.31 |
+01:06:38.8 |
HIP 56377 |
27.72 |
| 2026-02-05 12:00 |
11:34:31.59 |
+01:07:23.9 |
HIP 56377 |
25.65 |
| 2026-02-06 00:00 |
11:34:16.72 |
+01:08:10.1 |
HIP 56377 |
23.99 |
| 2026-02-06 12:00 |
11:34:01.70 |
+01:08:57.2 |
HIP 56377 |
22.84 |
| 2026-02-07 00:00 |
11:33:46.53 |
+01:09:45.3 |
HIP 56307 |
20.51 |
| 2026-02-07 12:00 |
11:33:31.22 |
+01:10:34.4 |
HIP 56307 |
16.86 |
| 2026-02-08 00:00 |
11:33:15.76 |
+01:11:24.5 |
HIP 56307 |
13.33 |
| 2026-02-08 12:00 |
11:33:00.15 |
+01:12:15.4 |
HIP 56307 |
10.09 |
| 2026-02-09 00:00 |
11:32:44.41 |
+01:13:07.4 |
HIP 56307 |
7.56 |
| 2026-02-09 12:00 |
11:32:28.53 |
+01:14:00.2 |
HIP 56307 |
6.71 |
| 2026-02-10 00:00 |
11:32:12.52 |
+01:14:54.0 |
HIP 56307 |
8.14 |
| 2026-02-10 12:00 |
11:31:56.37 |
+01:15:48.7 |
HIP 56307 |
11.03 |
| 2026-02-11 00:00 |
11:31:40.09 |
+01:16:44.2 |
HIP 56307 |
14.56 |
| 2026-02-11 12:00 |
11:31:23.68 |
+01:17:40.7 |
HIP 56307 |
18.39 |
| 2026-02-12 00:00 |
11:31:07.14 |
+01:18:38.0 |
HIP 56307 |
22.39 |
| 2026-02-12 12:00 |
11:30:50.48 |
+01:19:36.2 |
HIP 56307 |
26.50 |
| 2026-02-13 00:00 |
11:30:33.69 |
+01:20:35.2 |
HIP 56015 |
27.93 |
| 2026-02-13 12:00 |
11:30:16.79 |
+01:21:35.0 |
HIP 56015 |
24.30 |
| 2026-02-14 00:00 |
11:29:59.77 |
+01:22:35.7 |
HIP 56015 |
20.92 |
| 2026-02-14 12:00 |
11:29:42.64 |
+01:23:37.2 |
HIP 56015 |
17.96 |
| 2026-02-15 00:00 |
11:29:25.39 |
+01:24:39.4 |
HIP 56015 |
15.69 |
| 2026-02-15 12:00 |
11:29:08.03 |
+01:25:42.5 |
HIP 56015 |
14.46 |
| 2026-02-16 00:00 |
11:28:50.57 |
+01:26:46.3 |
HIP 56015 |
14.57 |
| 2026-02-16 12:00 |
11:28:33.00 |
+01:27:50.8 |
HIP 56015 |
16.01 |
| 2026-02-17 00:00 |
11:28:15.33 |
+01:28:56.1 |
HIP 55906 |
15.06 |
| 2026-02-17 12:00 |
11:27:57.57 |
+01:30:02.1 |
HIP 55906 |
13.37 |
| 2026-02-18 00:00 |
11:27:39.70 |
+01:31:08.7 |
HIP 55906 |
13.15 |
| 2026-02-18 12:00 |
11:27:21.75 |
+01:32:16.1 |
HIP 55906 |
14.48 |
| 2026-02-19 00:00 |
11:27:03.70 |
+01:33:24.2 |
HIP 55906 |
17.03 |
| 2026-02-19 12:00 |
11:26:45.57 |
+01:34:32.8 |
HIP 55906 |
20.36 |
| 2026-02-20 00:00 |
11:26:27.35 |
+01:35:42.2 |
HIP 55906 |
24.16 |
| 2026-02-20 12:00 |
11:26:09.05 |
+01:36:52.1 |
HIP 55906 |
28.25 |
| 2026-02-21 00:00 |
11:25:50.67 |
+01:38:02.7 |
HIP 55703 |
27.69 |
| 2026-02-21 12:00 |
11:25:32.22 |
+01:39:13.8 |
HIP 55703 |
26.58 |
| 2026-02-22 00:00 |
11:25:13.69 |
+01:40:25.5 |
HIP 55650 |
23.93 |
| 2026-02-22 12:00 |
11:24:55.10 |
+01:41:37.8 |
HIP 55650 |
21.64 |
| 2026-02-23 00:00 |
11:24:36.43 |
+01:42:50.6 |
HIP 55650 |
20.26 |
| 2026-02-23 12:00 |
11:24:17.71 |
+01:44:03.9 |
HIP 55650 |
19.97 |
| 2026-02-24 00:00 |
11:23:58.92 |
+01:45:17.7 |
HIP 55650 |
20.85 |