| Parameter |
Value |
| Designation |
C/1917 H1 (Schaumasse) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1917-05-18T16:57:51.399360Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:02Z |
| Obs used |
45 |
| NEO |
- |
| M1 |
12.000 |
| K1 |
31.250 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1917-05-25.0000000 |
| e |
1.00006471 |
| q (au) |
0.764170 |
| a (au) |
-11809.001775 |
| i (deg) |
158.739267 |
| Ω (om, deg) |
10.829618 |
| ω (w, deg) |
119.148065 |
| M (ma, deg) |
0.000005 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.089 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.089 |
| n |
6.000 |
| gf |
0.800 |
| gb |
-1.000 |
| k |
1.000 |
| 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) |
| 2026-06-01 00:00 |
05:18:08.79 |
+03:24:46.1 |
HIP 24729 |
6.94 |
| 2026-06-01 12:00 |
05:18:09.68 |
+03:24:47.9 |
HIP 24729 |
6.95 |
| 2026-06-02 00:00 |
05:18:10.57 |
+03:24:49.6 |
HIP 24729 |
6.98 |
| 2026-06-02 12:00 |
05:18:11.47 |
+03:24:51.3 |
HIP 24729 |
7.01 |
| 2026-06-03 00:00 |
05:18:12.37 |
+03:24:52.9 |
HIP 24729 |
7.04 |
| 2026-06-03 12:00 |
05:18:13.26 |
+03:24:54.6 |
HIP 24729 |
7.09 |
| 2026-06-04 00:00 |
05:18:14.16 |
+03:24:56.1 |
HIP 24729 |
7.14 |
| 2026-06-04 12:00 |
05:18:15.06 |
+03:24:57.7 |
HIP 24729 |
7.19 |
| 2026-06-05 00:00 |
05:18:15.96 |
+03:24:59.2 |
HIP 24729 |
7.25 |
| 2026-06-05 12:00 |
05:18:16.86 |
+03:25:00.7 |
HIP 24729 |
7.32 |
| 2026-06-06 00:00 |
05:18:17.77 |
+03:25:02.1 |
HIP 24729 |
7.39 |
| 2026-06-06 12:00 |
05:18:18.67 |
+03:25:03.5 |
HIP 24729 |
7.47 |
| 2026-06-07 00:00 |
05:18:19.57 |
+03:25:04.8 |
HIP 24729 |
7.56 |
| 2026-06-07 12:00 |
05:18:20.48 |
+03:25:06.2 |
HIP 24729 |
7.65 |
| 2026-06-08 00:00 |
05:18:21.38 |
+03:25:07.4 |
HIP 24729 |
7.74 |
| 2026-06-08 12:00 |
05:18:22.29 |
+03:25:08.7 |
HIP 24729 |
7.84 |
| 2026-06-09 00:00 |
05:18:23.19 |
+03:25:09.9 |
HIP 24729 |
7.94 |
| 2026-06-09 12:00 |
05:18:24.10 |
+03:25:11.0 |
HIP 24729 |
8.05 |
| 2026-06-10 00:00 |
05:18:25.01 |
+03:25:12.1 |
HIP 24729 |
8.16 |
| 2026-06-10 12:00 |
05:18:25.91 |
+03:25:13.2 |
HIP 24729 |
8.28 |
| 2026-06-11 00:00 |
05:18:26.82 |
+03:25:14.3 |
HIP 24729 |
8.40 |
| 2026-06-11 12:00 |
05:18:27.73 |
+03:25:15.3 |
HIP 24729 |
8.53 |
| 2026-06-12 00:00 |
05:18:28.64 |
+03:25:16.2 |
HIP 24729 |
8.65 |
| 2026-06-12 12:00 |
05:18:29.54 |
+03:25:17.2 |
HIP 24729 |
8.79 |
| 2026-06-13 00:00 |
05:18:30.45 |
+03:25:18.0 |
HIP 24729 |
8.92 |
| 2026-06-13 12:00 |
05:18:31.36 |
+03:25:18.9 |
HIP 24729 |
9.06 |
| 2026-06-14 00:00 |
05:18:32.26 |
+03:25:19.7 |
HIP 24729 |
9.20 |
| 2026-06-14 12:00 |
05:18:33.17 |
+03:25:20.5 |
HIP 24729 |
9.34 |
| 2026-06-15 00:00 |
05:18:34.08 |
+03:25:21.2 |
HIP 24729 |
9.49 |
| 2026-06-15 12:00 |
05:18:34.98 |
+03:25:21.9 |
HIP 24729 |
9.64 |
| 2026-06-16 00:00 |
05:18:35.89 |
+03:25:22.5 |
HIP 24729 |
9.79 |
| 2026-06-16 12:00 |
05:18:36.79 |
+03:25:23.1 |
HIP 24729 |
9.95 |
| 2026-06-17 00:00 |
05:18:37.70 |
+03:25:23.7 |
HIP 24729 |
10.10 |
| 2026-06-17 12:00 |
05:18:38.60 |
+03:25:24.2 |
HIP 24729 |
10.26 |
| 2026-06-18 00:00 |
05:18:39.50 |
+03:25:24.7 |
HIP 24729 |
10.42 |
| 2026-06-18 12:00 |
05:18:40.40 |
+03:25:25.1 |
HIP 24729 |
10.58 |
| 2026-06-19 00:00 |
05:18:41.31 |
+03:25:25.5 |
HIP 24729 |
10.74 |
| 2026-06-19 12:00 |
05:18:42.20 |
+03:25:25.9 |
HIP 24729 |
10.91 |
| 2026-06-20 00:00 |
05:18:43.10 |
+03:25:26.2 |
HIP 24729 |
11.07 |
| 2026-06-20 12:00 |
05:18:44.00 |
+03:25:26.5 |
HIP 24729 |
11.24 |
| 2026-06-21 00:00 |
05:18:44.90 |
+03:25:26.8 |
HIP 24729 |
11.41 |
| 2026-06-21 12:00 |
05:18:45.79 |
+03:25:27.0 |
HIP 24729 |
11.58 |
| 2026-06-22 00:00 |
05:18:46.69 |
+03:25:27.1 |
HIP 24729 |
11.75 |