| Parameter |
Value |
| Designation |
C/2013 D1 (Holvorcem) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2013-04-13T17:17:27.458880Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:30Z |
| Obs used |
118 |
| NEO |
- |
| M1 |
13.500 |
| K1 |
10.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2013-03-26.0000000 |
| e |
0.78087861 |
| q (au) |
2.460129 |
| a (au) |
11.227243 |
| i (deg) |
10.093564 |
| Ω (om, deg) |
294.974884 |
| ω (w, deg) |
252.631501 |
| M (ma, deg) |
359.509532 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.750 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.750 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.790 |
| k |
0.800 |
| δ90 |
5.227 |
| 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 |
23:42:22.17 |
+07:34:40.2 |
HIP 116918 |
20.62 |
| 2026-06-01 12:00 |
23:42:24.26 |
+07:35:09.0 |
HIP 116918 |
21.24 |
| 2026-06-02 00:00 |
23:42:26.30 |
+07:35:37.6 |
HIP 116918 |
21.86 |
| 2026-06-02 12:00 |
23:42:28.30 |
+07:36:05.9 |
HIP 116918 |
22.47 |
| 2026-06-03 00:00 |
23:42:30.25 |
+07:36:34.0 |
HIP 116918 |
23.08 |
| 2026-06-03 12:00 |
23:42:32.16 |
+07:37:01.8 |
HIP 116918 |
23.68 |
| 2026-06-04 00:00 |
23:42:34.02 |
+07:37:29.4 |
HIP 116918 |
24.28 |
| 2026-06-04 12:00 |
23:42:35.84 |
+07:37:56.8 |
HIP 116918 |
24.88 |
| 2026-06-05 00:00 |
23:42:37.61 |
+07:38:23.9 |
HIP 116918 |
25.47 |
| 2026-06-05 12:00 |
23:42:39.34 |
+07:38:50.7 |
HIP 116918 |
26.05 |
| 2026-06-06 00:00 |
23:42:41.02 |
+07:39:17.3 |
HIP 116918 |
26.62 |
| 2026-06-06 12:00 |
23:42:42.66 |
+07:39:43.7 |
HIP 116918 |
27.19 |
| 2026-06-07 00:00 |
23:42:44.25 |
+07:40:09.7 |
HIP 116918 |
27.75 |
| 2026-06-07 12:00 |
23:42:45.79 |
+07:40:35.6 |
HIP 116918 |
28.30 |
| 2026-06-08 00:00 |
23:42:47.29 |
+07:41:01.1 |
HIP 116918 |
28.85 |
| 2026-06-08 12:00 |
23:42:48.74 |
+07:41:26.4 |
HIP 116918 |
29.38 |
| 2026-06-09 00:00 |
23:42:50.14 |
+07:41:51.5 |
HIP 116918 |
29.91 |
| 2026-06-09 12:00 |
23:42:51.50 |
+07:42:16.2 |
HIP 116918 |
30.43 |
| 2026-06-10 00:00 |
23:42:52.81 |
+07:42:40.7 |
HIP 116918 |
30.94 |
| 2026-06-10 12:00 |
23:42:54.07 |
+07:43:05.0 |
HIP 116918 |
31.44 |
| 2026-06-11 00:00 |
23:42:55.29 |
+07:43:28.9 |
HIP 116918 |
31.94 |
| 2026-06-11 12:00 |
23:42:56.46 |
+07:43:52.6 |
HIP 116918 |
32.42 |
| 2026-06-12 00:00 |
23:42:57.58 |
+07:44:16.0 |
HIP 117063 |
32.77 |
| 2026-06-12 12:00 |
23:42:58.65 |
+07:44:39.2 |
HIP 117063 |
32.99 |
| 2026-06-13 00:00 |
23:42:59.68 |
+07:45:02.0 |
HIP 117063 |
33.23 |
| 2026-06-13 12:00 |
23:43:00.66 |
+07:45:24.6 |
HIP 117063 |
33.47 |
| 2026-06-14 00:00 |
23:43:01.59 |
+07:45:46.9 |
HIP 117063 |
33.71 |
| 2026-06-14 12:00 |
23:43:02.48 |
+07:46:08.9 |
HIP 117063 |
33.96 |
| 2026-06-15 00:00 |
23:43:03.31 |
+07:46:30.6 |
HIP 117063 |
34.21 |
| 2026-06-15 12:00 |
23:43:04.10 |
+07:46:52.1 |
HIP 117063 |
34.47 |
| 2026-06-16 00:00 |
23:43:04.84 |
+07:47:13.2 |
HIP 117063 |
34.72 |
| 2026-06-16 12:00 |
23:43:05.53 |
+07:47:34.1 |
HIP 117063 |
34.98 |
| 2026-06-17 00:00 |
23:43:06.17 |
+07:47:54.6 |
HIP 117063 |
35.25 |
| 2026-06-17 12:00 |
23:43:06.77 |
+07:48:14.9 |
HIP 117063 |
35.51 |
| 2026-06-18 00:00 |
23:43:07.31 |
+07:48:34.9 |
HIP 117063 |
35.78 |
| 2026-06-18 12:00 |
23:43:07.81 |
+07:48:54.6 |
HIP 117063 |
36.04 |
| 2026-06-19 00:00 |
23:43:08.26 |
+07:49:14.0 |
HIP 117063 |
36.31 |
| 2026-06-19 12:00 |
23:43:08.66 |
+07:49:33.1 |
HIP 117063 |
36.58 |
| 2026-06-20 00:00 |
23:43:09.02 |
+07:49:51.9 |
HIP 117063 |
36.85 |
| 2026-06-20 12:00 |
23:43:09.32 |
+07:50:10.3 |
HIP 117063 |
37.11 |
| 2026-06-21 00:00 |
23:43:09.58 |
+07:50:28.5 |
HIP 117063 |
37.38 |
| 2026-06-21 12:00 |
23:43:09.79 |
+07:50:46.4 |
HIP 117063 |
37.65 |
| 2026-06-22 00:00 |
23:43:09.95 |
+07:51:04.0 |
HIP 117063 |
37.92 |