C/1939 H1 (Jurlof-Achmarof-Hassel)
| Parameter |
Value |
| Designation |
C/1939 H1 (Jurlof-Achmarof-Hassel) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1939-04-10T02:44:02.135040Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:05Z |
| Obs used |
14 |
| NEO |
- |
| M1 |
6.000 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1939-05-07.0000000 |
| e |
0.99150316 |
| q (au) |
0.528255 |
| a (au) |
62.170794 |
| i (deg) |
138.167852 |
| Ω (om, deg) |
312.348989 |
| ω (w, deg) |
89.151721 |
| M (ma, deg) |
0.054057 |
Magnitude
Scatter + Global Linear
$$
M_a = (5.872 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
5.872 |
| n |
2.000 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
0.965 |
| 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) |
| 2026-02-03 00:00 |
03:50:30.60 |
-22:41:27.1 |
HIP 18087 |
20.25 |
| 2026-02-03 12:00 |
03:50:30.18 |
-22:41:14.6 |
HIP 18087 |
20.35 |
| 2026-02-04 00:00 |
03:50:29.77 |
-22:41:02.1 |
HIP 18087 |
20.45 |
| 2026-02-04 12:00 |
03:50:29.37 |
-22:40:49.5 |
HIP 18087 |
20.55 |
| 2026-02-05 00:00 |
03:50:28.98 |
-22:40:36.8 |
HIP 18087 |
20.65 |
| 2026-02-05 12:00 |
03:50:28.61 |
-22:40:24.1 |
HIP 18087 |
20.75 |
| 2026-02-06 00:00 |
03:50:28.25 |
-22:40:11.3 |
HIP 18087 |
20.84 |
| 2026-02-06 12:00 |
03:50:27.90 |
-22:39:58.4 |
HIP 18087 |
20.94 |
| 2026-02-07 00:00 |
03:50:27.56 |
-22:39:45.5 |
HIP 18087 |
21.03 |
| 2026-02-07 12:00 |
03:50:27.24 |
-22:39:32.6 |
HIP 18087 |
21.13 |
| 2026-02-08 00:00 |
03:50:26.92 |
-22:39:19.6 |
HIP 18087 |
21.22 |
| 2026-02-08 12:00 |
03:50:26.62 |
-22:39:06.6 |
HIP 18087 |
21.32 |
| 2026-02-09 00:00 |
03:50:26.34 |
-22:38:53.5 |
HIP 18087 |
21.41 |
| 2026-02-09 12:00 |
03:50:26.06 |
-22:38:40.4 |
HIP 18087 |
21.50 |
| 2026-02-10 00:00 |
03:50:25.80 |
-22:38:27.2 |
HIP 18087 |
21.59 |
| 2026-02-10 12:00 |
03:50:25.55 |
-22:38:13.9 |
HIP 18087 |
21.68 |
| 2026-02-11 00:00 |
03:50:25.32 |
-22:38:00.7 |
HIP 18087 |
21.77 |
| 2026-02-11 12:00 |
03:50:25.09 |
-22:37:47.4 |
HIP 18087 |
21.86 |
| 2026-02-12 00:00 |
03:50:24.88 |
-22:37:34.0 |
HIP 18087 |
21.95 |
| 2026-02-12 12:00 |
03:50:24.68 |
-22:37:20.6 |
HIP 18087 |
22.03 |
| 2026-02-13 00:00 |
03:50:24.50 |
-22:37:07.2 |
HIP 18087 |
22.12 |
| 2026-02-13 12:00 |
03:50:24.32 |
-22:36:53.7 |
HIP 18087 |
22.21 |
| 2026-02-14 00:00 |
03:50:24.16 |
-22:36:40.2 |
HIP 18087 |
22.29 |
| 2026-02-14 12:00 |
03:50:24.02 |
-22:36:26.6 |
HIP 18087 |
22.38 |
| 2026-02-15 00:00 |
03:50:23.88 |
-22:36:13.0 |
HIP 18087 |
22.46 |
| 2026-02-15 12:00 |
03:50:23.76 |
-22:35:59.4 |
HIP 18087 |
22.54 |
| 2026-02-16 00:00 |
03:50:23.65 |
-22:35:45.8 |
HIP 18087 |
22.63 |
| 2026-02-16 12:00 |
03:50:23.55 |
-22:35:32.1 |
HIP 18087 |
22.71 |
| 2026-02-17 00:00 |
03:50:23.47 |
-22:35:18.4 |
HIP 18087 |
22.79 |
| 2026-02-17 12:00 |
03:50:23.40 |
-22:35:04.6 |
HIP 18087 |
22.87 |
| 2026-02-18 00:00 |
03:50:23.34 |
-22:34:50.8 |
HIP 18087 |
22.95 |
| 2026-02-18 12:00 |
03:50:23.29 |
-22:34:37.0 |
HIP 18087 |
23.03 |
| 2026-02-19 00:00 |
03:50:23.26 |
-22:34:23.2 |
HIP 18087 |
23.11 |
| 2026-02-19 12:00 |
03:50:23.24 |
-22:34:09.3 |
HIP 18087 |
23.18 |
| 2026-02-20 00:00 |
03:50:23.23 |
-22:33:55.5 |
HIP 18087 |
23.26 |
| 2026-02-20 12:00 |
03:50:23.23 |
-22:33:41.6 |
HIP 18087 |
23.34 |
| 2026-02-21 00:00 |
03:50:23.25 |
-22:33:27.6 |
HIP 18087 |
23.41 |
| 2026-02-21 12:00 |
03:50:23.28 |
-22:33:13.7 |
HIP 18087 |
23.49 |
| 2026-02-22 00:00 |
03:50:23.32 |
-22:32:59.7 |
HIP 18087 |
23.56 |
| 2026-02-22 12:00 |
03:50:23.38 |
-22:32:45.7 |
HIP 18087 |
23.64 |
| 2026-02-23 00:00 |
03:50:23.45 |
-22:32:31.7 |
HIP 18087 |
23.71 |
| 2026-02-23 12:00 |
03:50:23.53 |
-22:32:17.7 |
HIP 18087 |
23.79 |
| 2026-02-24 00:00 |
03:50:23.62 |
-22:32:03.7 |
HIP 18087 |
23.86 |