| Parameter |
Value |
| Designation |
C/1937 D1 (Wilk) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1937-02-21T12:38:22.404480Z |
| Orbit solution date (soln_date, UTC) |
2024-02-20T20:16:49Z |
| Obs used |
17 |
| NEO |
Yes |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1937-03-17.0000000 |
| e |
0.98064326 |
| q (au) |
0.618890 |
| a (au) |
31.972825 |
| i (deg) |
26.014023 |
| Ω (om, deg) |
58.270037 |
| ω (w, deg) |
31.457951 |
| M (ma, deg) |
0.127970 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.016 + 4.637\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.016 |
| n |
4.637 |
| gf |
0.800 |
| gb |
-1.000 |
| k |
0.940 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
17:48:09.28 |
-36:46:20.9 |
HIP 87139 |
2.73 |
| 2026-05-12 12:00 |
17:48:07.45 |
-36:46:24.6 |
HIP 87139 |
2.95 |
| 2026-05-13 00:00 |
17:48:05.60 |
-36:46:28.2 |
HIP 87139 |
3.20 |
| 2026-05-13 12:00 |
17:48:03.74 |
-36:46:31.8 |
HIP 87139 |
3.47 |
| 2026-05-14 00:00 |
17:48:01.87 |
-36:46:35.3 |
HIP 87139 |
3.76 |
| 2026-05-14 12:00 |
17:47:59.98 |
-36:46:38.7 |
HIP 87139 |
4.07 |
| 2026-05-15 00:00 |
17:47:58.09 |
-36:46:42.1 |
HIP 87139 |
4.39 |
| 2026-05-15 12:00 |
17:47:56.18 |
-36:46:45.5 |
HIP 87139 |
4.72 |
| 2026-05-16 00:00 |
17:47:54.26 |
-36:46:48.8 |
HIP 87139 |
5.06 |
| 2026-05-16 12:00 |
17:47:52.33 |
-36:46:52.0 |
HIP 87139 |
5.40 |
| 2026-05-17 00:00 |
17:47:50.39 |
-36:46:55.2 |
HIP 87139 |
5.76 |
| 2026-05-17 12:00 |
17:47:48.44 |
-36:46:58.4 |
HIP 87139 |
6.12 |
| 2026-05-18 00:00 |
17:47:46.48 |
-36:47:01.5 |
HIP 87139 |
6.48 |
| 2026-05-18 12:00 |
17:47:44.51 |
-36:47:04.5 |
HIP 87139 |
6.85 |
| 2026-05-19 00:00 |
17:47:42.53 |
-36:47:07.5 |
HIP 87139 |
7.23 |
| 2026-05-19 12:00 |
17:47:40.53 |
-36:47:10.5 |
HIP 87139 |
7.61 |
| 2026-05-20 00:00 |
17:47:38.53 |
-36:47:13.3 |
HIP 87139 |
7.99 |
| 2026-05-20 12:00 |
17:47:36.52 |
-36:47:16.2 |
HIP 87139 |
8.38 |
| 2026-05-21 00:00 |
17:47:34.50 |
-36:47:19.0 |
HIP 87139 |
8.77 |
| 2026-05-21 12:00 |
17:47:32.47 |
-36:47:21.7 |
HIP 87139 |
9.16 |
| 2026-05-22 00:00 |
17:47:30.43 |
-36:47:24.4 |
HIP 87139 |
9.55 |
| 2026-05-22 12:00 |
17:47:28.38 |
-36:47:27.0 |
HIP 87139 |
9.95 |
| 2026-05-23 00:00 |
17:47:26.32 |
-36:47:29.6 |
HIP 87139 |
10.35 |
| 2026-05-23 12:00 |
17:47:24.25 |
-36:47:32.1 |
HIP 87139 |
10.75 |
| 2026-05-24 00:00 |
17:47:22.18 |
-36:47:34.5 |
HIP 87139 |
11.16 |
| 2026-05-24 12:00 |
17:47:20.09 |
-36:47:36.9 |
HIP 87139 |
11.56 |
| 2026-05-25 00:00 |
17:47:18.00 |
-36:47:39.3 |
HIP 87139 |
11.97 |
| 2026-05-25 12:00 |
17:47:15.90 |
-36:47:41.6 |
HIP 87139 |
12.39 |
| 2026-05-26 00:00 |
17:47:13.79 |
-36:47:43.8 |
HIP 87139 |
12.80 |
| 2026-05-26 12:00 |
17:47:11.67 |
-36:47:46.0 |
HIP 87139 |
13.21 |
| 2026-05-27 00:00 |
17:47:09.55 |
-36:47:48.1 |
HIP 87139 |
13.63 |
| 2026-05-27 12:00 |
17:47:07.42 |
-36:47:50.2 |
HIP 87139 |
14.05 |
| 2026-05-28 00:00 |
17:47:05.28 |
-36:47:52.2 |
HIP 87139 |
14.47 |
| 2026-05-28 12:00 |
17:47:03.13 |
-36:47:54.2 |
HIP 86951 |
14.26 |
| 2026-05-29 00:00 |
17:47:00.98 |
-36:47:56.1 |
HIP 86951 |
13.93 |
| 2026-05-29 12:00 |
17:46:58.82 |
-36:47:57.9 |
HIP 86951 |
13.61 |
| 2026-05-30 00:00 |
17:46:56.65 |
-36:47:59.7 |
HIP 86951 |
13.29 |
| 2026-05-30 12:00 |
17:46:54.48 |
-36:48:01.5 |
HIP 86951 |
12.98 |
| 2026-05-31 00:00 |
17:46:52.30 |
-36:48:03.2 |
HIP 86951 |
12.67 |
| 2026-05-31 12:00 |
17:46:50.12 |
-36:48:04.8 |
HIP 86951 |
12.37 |
| 2026-06-01 00:00 |
17:46:47.92 |
-36:48:06.4 |
HIP 86951 |
12.07 |
| 2026-06-01 12:00 |
17:46:45.73 |
-36:48:07.9 |
HIP 86951 |
11.78 |
| 2026-06-02 00:00 |
17:46:43.52 |
-36:48:09.3 |
HIP 86951 |
11.50 |