| 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) |
| 2026-07-29 00:00 |
05:19:45.21 |
+03:23:51.4 |
HIP 24830 |
17.44 |
| 2026-07-29 12:00 |
05:19:45.85 |
+03:23:48.7 |
HIP 24830 |
17.45 |
| 2026-07-30 00:00 |
05:19:46.48 |
+03:23:46.0 |
HIP 24830 |
17.46 |
| 2026-07-30 12:00 |
05:19:47.10 |
+03:23:43.3 |
HIP 24830 |
17.47 |
| 2026-07-31 00:00 |
05:19:47.72 |
+03:23:40.5 |
HIP 24830 |
17.48 |
| 2026-07-31 12:00 |
05:19:48.33 |
+03:23:37.7 |
HIP 24830 |
17.49 |
| 2026-08-01 00:00 |
05:19:48.94 |
+03:23:34.9 |
HIP 24830 |
17.50 |
| 2026-08-01 12:00 |
05:19:49.54 |
+03:23:32.0 |
HIP 24830 |
17.52 |
| 2026-08-02 00:00 |
05:19:50.13 |
+03:23:29.1 |
HIP 24830 |
17.53 |
| 2026-08-02 12:00 |
05:19:50.72 |
+03:23:26.2 |
HIP 24830 |
17.54 |
| 2026-08-03 00:00 |
05:19:51.31 |
+03:23:23.2 |
HIP 24830 |
17.56 |
| 2026-08-03 12:00 |
05:19:51.88 |
+03:23:20.2 |
HIP 24830 |
17.57 |
| 2026-08-04 00:00 |
05:19:52.46 |
+03:23:17.2 |
HIP 24830 |
17.59 |
| 2026-08-04 12:00 |
05:19:53.02 |
+03:23:14.1 |
HIP 24830 |
17.60 |
| 2026-08-05 00:00 |
05:19:53.58 |
+03:23:11.0 |
HIP 24830 |
17.62 |
| 2026-08-05 12:00 |
05:19:54.14 |
+03:23:07.9 |
HIP 24830 |
17.63 |
| 2026-08-06 00:00 |
05:19:54.68 |
+03:23:04.8 |
HIP 24830 |
17.64 |
| 2026-08-06 12:00 |
05:19:55.23 |
+03:23:01.6 |
HIP 24830 |
17.66 |
| 2026-08-07 00:00 |
05:19:55.76 |
+03:22:58.4 |
HIP 24830 |
17.67 |
| 2026-08-07 12:00 |
05:19:56.29 |
+03:22:55.1 |
HIP 24830 |
17.69 |
| 2026-08-08 00:00 |
05:19:56.81 |
+03:22:51.8 |
HIP 24830 |
17.70 |
| 2026-08-08 12:00 |
05:19:57.33 |
+03:22:48.5 |
HIP 24830 |
17.72 |
| 2026-08-09 00:00 |
05:19:57.84 |
+03:22:45.2 |
HIP 24830 |
17.73 |
| 2026-08-09 12:00 |
05:19:58.35 |
+03:22:41.9 |
HIP 24830 |
17.75 |
| 2026-08-10 00:00 |
05:19:58.84 |
+03:22:38.5 |
HIP 24830 |
17.76 |
| 2026-08-10 12:00 |
05:19:59.34 |
+03:22:35.0 |
HIP 24830 |
17.78 |
| 2026-08-11 00:00 |
05:19:59.82 |
+03:22:31.6 |
HIP 24830 |
17.79 |
| 2026-08-11 12:00 |
05:20:00.30 |
+03:22:28.1 |
HIP 24830 |
17.80 |
| 2026-08-12 00:00 |
05:20:00.77 |
+03:22:24.6 |
HIP 24830 |
17.82 |
| 2026-08-12 12:00 |
05:20:01.24 |
+03:22:21.1 |
HIP 24830 |
17.83 |
| 2026-08-13 00:00 |
05:20:01.70 |
+03:22:17.5 |
HIP 24830 |
17.84 |
| 2026-08-13 12:00 |
05:20:02.15 |
+03:22:13.9 |
HIP 24830 |
17.86 |
| 2026-08-14 00:00 |
05:20:02.59 |
+03:22:10.3 |
HIP 24830 |
17.87 |
| 2026-08-14 12:00 |
05:20:03.03 |
+03:22:06.7 |
HIP 24830 |
17.88 |
| 2026-08-15 00:00 |
05:20:03.46 |
+03:22:03.0 |
HIP 24830 |
17.89 |
| 2026-08-15 12:00 |
05:20:03.89 |
+03:21:59.3 |
HIP 24830 |
17.90 |
| 2026-08-16 00:00 |
05:20:04.30 |
+03:21:55.6 |
HIP 24830 |
17.91 |
| 2026-08-16 12:00 |
05:20:04.72 |
+03:21:51.9 |
HIP 24830 |
17.92 |
| 2026-08-17 00:00 |
05:20:05.12 |
+03:21:48.1 |
HIP 24830 |
17.93 |
| 2026-08-17 12:00 |
05:20:05.52 |
+03:21:44.3 |
HIP 24830 |
17.94 |
| 2026-08-18 00:00 |
05:20:05.91 |
+03:21:40.5 |
HIP 24830 |
17.94 |
| 2026-08-18 12:00 |
05:20:06.29 |
+03:21:36.6 |
HIP 24830 |
17.95 |
| 2026-08-19 00:00 |
05:20:06.67 |
+03:21:32.7 |
HIP 24830 |
17.96 |