| Parameter |
Value |
| Designation |
C/1951 G1 (Groeneveld) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1951-11-08T09:50:31.205760Z |
| Orbit solution date (soln_date, UTC) |
2023-04-24T19:06:50Z |
| Obs used |
9 |
| NEO |
- |
| M1 |
5.900 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
1951-04-02T04:09:59.040000Z |
| Discovery magnitude (MPC) |
15.00 T |
| Discovery observatory (MPC) |
711 · McDonald Observatory, Fort Davis |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1951-04-02.0000000 |
| e |
1.01297450 |
| q (au) |
3.625080 |
| a (au) |
-279.400392 |
| i (deg) |
18.650997 |
| Ω (om, deg) |
31.526922 |
| ω (w, deg) |
188.119857 |
| M (ma, deg) |
-0.046515 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.162 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.162 |
| n |
2.000 |
| gf |
0.802 |
| gb |
-0.922 |
| k |
0.950 |
| 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) |
| 2026-09-20 00:00 |
01:09:51.76 |
+02:01:54.0 |
HIP 5510 |
26.95 |
| 2026-09-20 12:00 |
01:09:50.76 |
+02:01:47.4 |
HIP 5510 |
27.15 |
| 2026-09-21 00:00 |
01:09:49.75 |
+02:01:40.8 |
HIP 5510 |
27.35 |
| 2026-09-21 12:00 |
01:09:48.74 |
+02:01:34.2 |
HIP 5315 |
27.34 |
| 2026-09-22 00:00 |
01:09:47.72 |
+02:01:27.6 |
HIP 5315 |
27.08 |
| 2026-09-22 12:00 |
01:09:46.70 |
+02:01:21.0 |
HIP 5315 |
26.82 |
| 2026-09-23 00:00 |
01:09:45.68 |
+02:01:14.4 |
HIP 5315 |
26.56 |
| 2026-09-23 12:00 |
01:09:44.65 |
+02:01:07.7 |
HIP 5315 |
26.29 |
| 2026-09-24 00:00 |
01:09:43.63 |
+02:01:01.1 |
HIP 5315 |
26.03 |
| 2026-09-24 12:00 |
01:09:42.59 |
+02:00:54.5 |
HIP 5315 |
25.77 |
| 2026-09-25 00:00 |
01:09:41.56 |
+02:00:47.8 |
HIP 5315 |
25.51 |
| 2026-09-25 12:00 |
01:09:40.52 |
+02:00:41.2 |
HIP 5315 |
25.24 |
| 2026-09-26 00:00 |
01:09:39.48 |
+02:00:34.5 |
HIP 5315 |
24.98 |
| 2026-09-26 12:00 |
01:09:38.44 |
+02:00:27.9 |
HIP 5315 |
24.71 |
| 2026-09-27 00:00 |
01:09:37.40 |
+02:00:21.2 |
HIP 5315 |
24.45 |
| 2026-09-27 12:00 |
01:09:36.35 |
+02:00:14.6 |
HIP 5315 |
24.18 |
| 2026-09-28 00:00 |
01:09:35.30 |
+02:00:07.9 |
HIP 5315 |
23.92 |
| 2026-09-28 12:00 |
01:09:34.25 |
+02:00:01.3 |
HIP 5315 |
23.66 |
| 2026-09-29 00:00 |
01:09:33.19 |
+01:59:54.6 |
HIP 5315 |
23.39 |
| 2026-09-29 12:00 |
01:09:32.14 |
+01:59:48.0 |
HIP 5315 |
23.13 |
| 2026-09-30 00:00 |
01:09:31.08 |
+01:59:41.3 |
HIP 5315 |
22.86 |
| 2026-09-30 12:00 |
01:09:30.02 |
+01:59:34.6 |
HIP 5315 |
22.60 |
| 2026-10-01 00:00 |
01:09:28.95 |
+01:59:28.0 |
HIP 5315 |
22.33 |
| 2026-10-01 12:00 |
01:09:27.89 |
+01:59:21.3 |
HIP 5315 |
22.07 |
| 2026-10-02 00:00 |
01:09:26.82 |
+01:59:14.7 |
HIP 5315 |
21.80 |
| 2026-10-02 12:00 |
01:09:25.76 |
+01:59:08.0 |
HIP 5315 |
21.54 |
| 2026-10-03 00:00 |
01:09:24.69 |
+01:59:01.4 |
HIP 5315 |
21.27 |
| 2026-10-03 12:00 |
01:09:23.61 |
+01:58:54.8 |
HIP 5315 |
21.01 |
| 2026-10-04 00:00 |
01:09:22.54 |
+01:58:48.1 |
HIP 5315 |
20.74 |
| 2026-10-04 12:00 |
01:09:21.47 |
+01:58:41.5 |
HIP 5315 |
20.48 |
| 2026-10-05 00:00 |
01:09:20.39 |
+01:58:34.9 |
HIP 5315 |
20.22 |
| 2026-10-05 12:00 |
01:09:19.31 |
+01:58:28.3 |
HIP 5315 |
19.96 |
| 2026-10-06 00:00 |
01:09:18.24 |
+01:58:21.7 |
HIP 5315 |
19.69 |
| 2026-10-06 12:00 |
01:09:17.16 |
+01:58:15.1 |
HIP 5315 |
19.43 |
| 2026-10-07 00:00 |
01:09:16.08 |
+01:58:08.5 |
HIP 5315 |
19.17 |
| 2026-10-07 12:00 |
01:09:15.00 |
+01:58:01.9 |
HIP 5315 |
18.91 |
| 2026-10-08 00:00 |
01:09:13.91 |
+01:57:55.3 |
HIP 5315 |
18.65 |
| 2026-10-08 12:00 |
01:09:12.83 |
+01:57:48.8 |
HIP 5315 |
18.39 |
| 2026-10-09 00:00 |
01:09:11.75 |
+01:57:42.2 |
HIP 5315 |
18.14 |
| 2026-10-09 12:00 |
01:09:10.66 |
+01:57:35.7 |
HIP 5315 |
17.88 |
| 2026-10-10 00:00 |
01:09:09.58 |
+01:57:29.1 |
HIP 5315 |
17.62 |
| 2026-10-10 12:00 |
01:09:08.49 |
+01:57:22.6 |
HIP 5315 |
17.37 |
| 2026-10-11 00:00 |
01:09:07.41 |
+01:57:16.1 |
HIP 5315 |
17.11 |