| Parameter |
Value |
| Designation |
404P/Bressi |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2023-10-24T23:24:20.805120Z |
| Orbit solution date (soln_date, UTC) |
2026-03-17T15:12:47Z |
| Obs used |
785 |
| NEO |
- |
| M1 |
10.000 |
| K1 |
10.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2022-08-30.0000000 |
| e |
0.13286937 |
| q (au) |
4.135875 |
| a (au) |
4.769611 |
| i (deg) |
9.738129 |
| Ω (om, deg) |
260.353617 |
| ω (w, deg) |
167.853131 |
| M (ma, deg) |
320.167622 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.383 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.383 |
| n |
6.000 |
| gf |
0.948 |
| gb |
-0.845 |
| k |
1.000 |
| δ90 |
8.833 |
| 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 |
| 2020-06-17 |
2023-10-23 |
+4.6292 |
-2.683 |
| 2023-11-08 |
2026-03-14 |
+0.5720 |
-0.604 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
11:57:25.68 |
-08:21:00.7 |
HIP 58333 |
6.79 |
| 2026-09-20 12:00 |
11:57:52.54 |
-08:23:46.6 |
HIP 58333 |
7.44 |
| 2026-09-21 00:00 |
11:58:19.40 |
-08:26:32.6 |
HIP 58331 |
10.56 |
| 2026-09-21 12:00 |
11:58:46.26 |
-08:29:18.9 |
HIP 58331 |
15.48 |
| 2026-09-22 00:00 |
11:59:13.13 |
-08:32:05.5 |
HIP 58331 |
21.71 |
| 2026-09-22 12:00 |
11:59:40.00 |
-08:34:52.2 |
HIP 58331 |
28.40 |
| 2026-09-23 00:00 |
12:00:06.86 |
-08:37:39.2 |
HIP 58633 |
34.30 |
| 2026-09-23 12:00 |
12:00:33.73 |
-08:40:26.4 |
HIP 58633 |
33.53 |
| 2026-09-24 00:00 |
12:01:00.59 |
-08:43:13.8 |
HIP 58633 |
34.29 |
| 2026-09-24 12:00 |
12:01:27.46 |
-08:46:01.5 |
HIP 58633 |
36.49 |
| 2026-09-25 00:00 |
12:01:54.32 |
-08:48:49.3 |
HIP 58633 |
39.90 |
| 2026-09-25 12:00 |
12:02:21.18 |
-08:51:37.4 |
HIP 58865 |
41.63 |
| 2026-09-26 00:00 |
12:02:48.03 |
-08:54:25.6 |
HIP 58865 |
35.11 |
| 2026-09-26 12:00 |
12:03:14.89 |
-08:57:14.1 |
HIP 58865 |
28.91 |
| 2026-09-27 00:00 |
12:03:41.74 |
-09:00:02.7 |
HIP 58865 |
23.30 |
| 2026-09-27 12:00 |
12:04:08.58 |
-09:02:51.5 |
HIP 58865 |
18.80 |
| 2026-09-28 00:00 |
12:04:35.43 |
-09:05:40.5 |
HIP 58936 |
14.88 |
| 2026-09-28 12:00 |
12:05:02.26 |
-09:08:29.7 |
HIP 58936 |
10.06 |
| 2026-09-29 00:00 |
12:05:29.10 |
-09:11:19.1 |
HIP 58936 |
9.19 |
| 2026-09-29 12:00 |
12:05:55.92 |
-09:14:08.6 |
HIP 58936 |
13.08 |
| 2026-09-30 00:00 |
12:06:22.74 |
-09:16:58.4 |
HIP 59060 |
9.19 |
| 2026-09-30 12:00 |
12:06:49.56 |
-09:19:48.3 |
HIP 59060 |
5.02 |
| 2026-10-01 00:00 |
12:07:16.37 |
-09:22:38.3 |
HIP 59060 |
8.34 |
| 2026-10-01 12:00 |
12:07:43.17 |
-09:25:28.5 |
HIP 59060 |
14.74 |
| 2026-10-02 00:00 |
12:08:09.96 |
-09:28:18.9 |
HIP 59060 |
21.64 |
| 2026-10-02 12:00 |
12:08:36.74 |
-09:31:09.5 |
HIP 59060 |
28.69 |
| 2026-10-03 00:00 |
12:09:03.52 |
-09:34:00.1 |
HIP 59359 |
26.05 |
| 2026-10-03 12:00 |
12:09:30.28 |
-09:36:51.0 |
HIP 59359 |
21.64 |
| 2026-10-04 00:00 |
12:09:57.04 |
-09:39:41.9 |
HIP 59359 |
19.02 |
| 2026-10-04 12:00 |
12:10:23.78 |
-09:42:33.0 |
HIP 59359 |
18.93 |
| 2026-10-05 00:00 |
12:10:50.52 |
-09:45:24.3 |
HIP 59359 |
21.41 |
| 2026-10-05 12:00 |
12:11:17.24 |
-09:48:15.7 |
HIP 59367 |
25.45 |
| 2026-10-06 00:00 |
12:11:43.95 |
-09:51:07.2 |
HIP 59367 |
30.55 |
| 2026-10-06 12:00 |
12:12:10.65 |
-09:53:58.8 |
HIP 59625 |
31.53 |
| 2026-10-07 00:00 |
12:12:37.33 |
-09:56:50.5 |
HIP 59625 |
29.95 |
| 2026-10-07 12:00 |
12:13:04.00 |
-09:59:42.3 |
HIP 59625 |
30.05 |
| 2026-10-08 00:00 |
12:13:30.66 |
-10:02:34.3 |
HIP 59720 |
29.32 |
| 2026-10-08 12:00 |
12:13:57.30 |
-10:05:26.3 |
HIP 59750 |
22.31 |
| 2026-10-09 00:00 |
12:14:23.93 |
-10:08:18.5 |
HIP 59750 |
15.41 |
| 2026-10-09 12:00 |
12:14:50.53 |
-10:11:10.7 |
HIP 59750 |
8.90 |
| 2026-10-10 00:00 |
12:15:17.12 |
-10:14:03.0 |
HIP 59750 |
4.83 |
| 2026-10-10 12:00 |
12:15:43.70 |
-10:16:55.4 |
HIP 59750 |
8.33 |
| 2026-10-11 00:00 |
12:16:10.25 |
-10:19:47.9 |
HIP 59750 |
14.74 |