| 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) |
| 2026-05-12 00:00 |
04:00:53.40 |
+27:30:29.4 |
HIP 18779 |
9.49 |
| 2026-05-12 12:00 |
04:01:27.09 |
+27:31:46.2 |
HIP 18779 |
5.14 |
| 2026-05-13 00:00 |
04:02:00.80 |
+27:33:02.8 |
HIP 18779 |
8.81 |
| 2026-05-13 12:00 |
04:02:34.51 |
+27:34:19.2 |
HIP 18779 |
15.61 |
| 2026-05-14 00:00 |
04:03:08.23 |
+27:35:35.4 |
HIP 18779 |
22.90 |
| 2026-05-14 12:00 |
04:03:41.95 |
+27:36:51.5 |
HIP 19068 |
20.00 |
| 2026-05-15 00:00 |
04:04:15.68 |
+27:38:07.4 |
HIP 19068 |
12.62 |
| 2026-05-15 12:00 |
04:04:49.42 |
+27:39:23.1 |
HIP 19068 |
5.78 |
| 2026-05-16 00:00 |
04:05:23.16 |
+27:40:38.6 |
HIP 19068 |
4.72 |
| 2026-05-16 12:00 |
04:05:56.90 |
+27:41:53.9 |
HIP 19171 |
10.55 |
| 2026-05-17 00:00 |
04:06:30.64 |
+27:43:09.0 |
HIP 19171 |
7.26 |
| 2026-05-17 12:00 |
04:07:04.39 |
+27:44:23.9 |
HIP 19171 |
10.44 |
| 2026-05-18 00:00 |
04:07:38.14 |
+27:45:38.7 |
HIP 19219 |
16.32 |
| 2026-05-18 12:00 |
04:08:11.88 |
+27:46:53.2 |
HIP 19219 |
21.32 |
| 2026-05-19 00:00 |
04:08:45.63 |
+27:48:07.5 |
HIP 19219 |
27.52 |
| 2026-05-19 12:00 |
04:09:19.37 |
+27:49:21.6 |
HIP 19219 |
34.27 |
| 2026-05-20 00:00 |
04:09:53.11 |
+27:50:35.5 |
HIP 19219 |
41.31 |
| 2026-05-20 12:00 |
04:10:26.85 |
+27:51:49.2 |
HIP 19629 |
42.57 |
| 2026-05-21 00:00 |
04:11:00.59 |
+27:53:02.6 |
HIP 19629 |
37.54 |
| 2026-05-21 12:00 |
04:11:34.32 |
+27:54:15.9 |
HIP 19629 |
33.48 |
| 2026-05-22 00:00 |
04:12:08.04 |
+27:55:28.9 |
HIP 19629 |
30.76 |
| 2026-05-22 12:00 |
04:12:41.76 |
+27:56:41.7 |
HIP 19792 |
24.28 |
| 2026-05-23 00:00 |
04:13:15.47 |
+27:57:54.3 |
HIP 19792 |
16.82 |
| 2026-05-23 12:00 |
04:13:49.18 |
+27:59:06.6 |
HIP 19792 |
9.50 |
| 2026-05-24 00:00 |
04:14:22.87 |
+28:00:18.8 |
HIP 19792 |
3.34 |
| 2026-05-24 12:00 |
04:14:56.56 |
+28:01:30.7 |
HIP 19792 |
6.76 |
| 2026-05-25 00:00 |
04:15:30.24 |
+28:02:42.3 |
HIP 19792 |
13.91 |
| 2026-05-25 12:00 |
04:16:03.91 |
+28:03:53.8 |
HIP 19792 |
21.32 |
| 2026-05-26 00:00 |
04:16:37.57 |
+28:05:05.0 |
HIP 20090 |
24.22 |
| 2026-05-26 12:00 |
04:17:11.22 |
+28:06:15.9 |
HIP 20090 |
16.77 |
| 2026-05-27 00:00 |
04:17:44.86 |
+28:07:26.6 |
HIP 20090 |
9.44 |
| 2026-05-27 12:00 |
04:18:18.48 |
+28:08:37.1 |
HIP 20090 |
3.11 |
| 2026-05-28 00:00 |
04:18:52.09 |
+28:09:47.4 |
HIP 20090 |
6.55 |
| 2026-05-28 12:00 |
04:19:25.69 |
+28:10:57.4 |
HIP 20090 |
13.73 |
| 2026-05-29 00:00 |
04:19:59.28 |
+28:12:07.1 |
HIP 20090 |
21.13 |
| 2026-05-29 12:00 |
04:20:32.85 |
+28:13:16.6 |
HIP 20388 |
19.54 |
| 2026-05-30 00:00 |
04:21:06.41 |
+28:14:25.9 |
HIP 20388 |
12.12 |
| 2026-05-30 12:00 |
04:21:39.95 |
+28:15:34.9 |
HIP 20388 |
4.87 |
| 2026-05-31 00:00 |
04:22:13.48 |
+28:16:43.7 |
HIP 20388 |
3.51 |
| 2026-05-31 12:00 |
04:22:46.99 |
+28:17:52.2 |
HIP 20388 |
10.60 |
| 2026-06-01 00:00 |
04:23:20.48 |
+28:19:00.5 |
HIP 20512 |
9.36 |
| 2026-06-01 12:00 |
04:23:53.95 |
+28:20:08.6 |
HIP 20512 |
9.22 |
| 2026-06-02 00:00 |
04:24:27.41 |
+28:21:16.3 |
HIP 20512 |
13.90 |