| Parameter |
Value |
| Designation |
37P/Forbes |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-05-04T04:20:40.490880Z |
| Orbit solution date (soln_date, UTC) |
2025-11-23T22:22:59Z |
| Obs used |
1737 |
| NEO |
- |
| M1 |
9.600 |
| K1 |
21.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2019-07-09.0000000 |
| e |
0.53418886 |
| q (au) |
1.610684 |
| a (au) |
3.457805 |
| i (deg) |
8.956078 |
| Ω (om, deg) |
314.577863 |
| ω (w, deg) |
330.024671 |
| M (ma, deg) |
66.038643 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.398 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.398 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| k |
1.000 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2024-02-05 |
2024-10-07 |
+32.4582 |
-8.642 |
| 2024-10-07 |
2024-04-20 |
-1.5202 |
+0.726 |
| 2024-04-20 |
2025-01-05 |
+15.9337 |
-5.687 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
03:10:10.79 |
+25:26:05.9 |
HIP 14621 |
18.45 |
| 2026-03-26 12:00 |
03:10:40.86 |
+25:27:20.9 |
HIP 14621 |
25.34 |
| 2026-03-27 00:00 |
03:11:11.00 |
+25:28:36.2 |
HIP 14984 |
26.67 |
| 2026-03-27 12:00 |
03:11:41.21 |
+25:29:51.7 |
HIP 14984 |
19.78 |
| 2026-03-28 00:00 |
03:12:11.49 |
+25:31:07.5 |
HIP 14984 |
12.92 |
| 2026-03-28 12:00 |
03:12:41.84 |
+25:32:23.5 |
HIP 14984 |
6.25 |
| 2026-03-29 00:00 |
03:13:12.25 |
+25:33:39.8 |
HIP 14984 |
2.87 |
| 2026-03-29 12:00 |
03:13:42.74 |
+25:34:56.4 |
HIP 14984 |
8.66 |
| 2026-03-30 00:00 |
03:14:13.29 |
+25:36:13.1 |
HIP 14984 |
15.49 |
| 2026-03-30 12:00 |
03:14:43.91 |
+25:37:30.1 |
HIP 14984 |
22.45 |
| 2026-03-31 00:00 |
03:15:14.59 |
+25:38:47.3 |
HIP 15273 |
24.37 |
| 2026-03-31 12:00 |
03:15:45.34 |
+25:40:04.7 |
HIP 15273 |
17.85 |
| 2026-04-01 00:00 |
03:16:16.15 |
+25:41:22.3 |
HIP 15273 |
11.94 |
| 2026-04-01 12:00 |
03:16:47.02 |
+25:42:40.2 |
HIP 15273 |
8.15 |
| 2026-04-02 00:00 |
03:17:17.96 |
+25:43:58.2 |
HIP 15273 |
9.52 |
| 2026-04-02 12:00 |
03:17:48.96 |
+25:45:16.4 |
HIP 15273 |
14.68 |
| 2026-04-03 00:00 |
03:18:20.02 |
+25:46:34.7 |
HIP 15273 |
21.03 |
| 2026-04-03 12:00 |
03:18:51.14 |
+25:47:53.3 |
HIP 15512 |
18.18 |
| 2026-04-04 00:00 |
03:19:22.31 |
+25:49:12.0 |
HIP 15512 |
14.39 |
| 2026-04-04 12:00 |
03:19:53.55 |
+25:50:30.9 |
HIP 15557 |
12.93 |
| 2026-04-05 00:00 |
03:20:24.85 |
+25:51:49.9 |
HIP 15557 |
12.06 |
| 2026-04-05 12:00 |
03:20:56.20 |
+25:53:09.1 |
HIP 15557 |
15.05 |
| 2026-04-06 00:00 |
03:21:27.61 |
+25:54:28.4 |
HIP 15557 |
20.27 |
| 2026-04-06 12:00 |
03:21:59.08 |
+25:55:47.9 |
HIP 15557 |
26.45 |
| 2026-04-07 00:00 |
03:22:30.60 |
+25:57:07.5 |
HIP 15557 |
33.06 |
| 2026-04-07 12:00 |
03:23:02.18 |
+25:58:27.3 |
HIP 15958 |
32.19 |
| 2026-04-08 00:00 |
03:23:33.81 |
+25:59:47.1 |
HIP 15958 |
25.19 |
| 2026-04-08 12:00 |
03:24:05.50 |
+26:01:07.1 |
HIP 15958 |
18.36 |
| 2026-04-09 00:00 |
03:24:37.24 |
+26:02:27.2 |
HIP 15958 |
12.03 |
| 2026-04-09 12:00 |
03:25:09.03 |
+26:03:47.4 |
HIP 15958 |
7.59 |
| 2026-04-10 00:00 |
03:25:40.87 |
+26:05:07.7 |
HIP 15958 |
8.73 |
| 2026-04-10 12:00 |
03:26:12.77 |
+26:06:28.1 |
HIP 15958 |
14.18 |
| 2026-04-11 00:00 |
03:26:44.71 |
+26:07:48.6 |
HIP 15980 |
20.11 |
| 2026-04-11 12:00 |
03:27:16.71 |
+26:09:09.1 |
HIP 16171 |
16.13 |
| 2026-04-12 00:00 |
03:27:48.75 |
+26:10:29.8 |
HIP 16171 |
9.29 |
| 2026-04-12 12:00 |
03:28:20.84 |
+26:11:50.5 |
HIP 16171 |
4.40 |
| 2026-04-13 00:00 |
03:28:52.98 |
+26:13:11.3 |
HIP 16217 |
5.40 |
| 2026-04-13 12:00 |
03:29:25.17 |
+26:14:32.2 |
HIP 16217 |
7.53 |
| 2026-04-14 00:00 |
03:29:57.40 |
+26:15:53.1 |
HIP 16217 |
13.86 |
| 2026-04-14 12:00 |
03:30:29.68 |
+26:17:14.1 |
HIP 16431 |
14.39 |
| 2026-04-15 00:00 |
03:31:02.01 |
+26:18:35.1 |
HIP 16431 |
7.56 |
| 2026-04-15 12:00 |
03:31:34.37 |
+26:19:56.2 |
HIP 16431 |
4.01 |
| 2026-04-16 00:00 |
03:32:06.79 |
+26:21:17.3 |
HIP 16431 |
9.16 |