| Parameter |
Value |
| Designation |
C/1951 G2 (Groeneveld-Palomar) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1950-07-11T23:45:37.175040Z |
| Orbit solution date (soln_date, UTC) |
2023-07-24T16:29:21Z |
| Obs used |
9 |
| NEO |
- |
| M1 |
5.900 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
1951-04-09T05:11:02.400000Z |
| Discovery magnitude (MPC) |
14.50 T |
| Discovery observatory (MPC) |
711 · McDonald Observatory, Fort Davis |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1951-04-14.0000000 |
| e |
1.00090094 |
| q (au) |
3.638504 |
| a (au) |
-4038.551574 |
| i (deg) |
170.654005 |
| Ω (om, deg) |
354.318294 |
| ω (w, deg) |
108.662689 |
| M (ma, deg) |
0.001060 |
Magnitude
Scatter + Global Linear
$$
M_a = (4.160 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
4.160 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.566 |
| k |
0.800 |
| δ90 |
10.000 |
| 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 |
05:54:11.40 |
+14:06:45.0 |
HIP 27961 |
12.42 |
| 2026-09-20 12:00 |
05:54:11.38 |
+14:06:42.0 |
HIP 27961 |
12.45 |
| 2026-09-21 00:00 |
05:54:11.35 |
+14:06:39.1 |
HIP 27961 |
12.48 |
| 2026-09-21 12:00 |
05:54:11.31 |
+14:06:36.1 |
HIP 27961 |
12.51 |
| 2026-09-22 00:00 |
05:54:11.26 |
+14:06:33.1 |
HIP 27961 |
12.55 |
| 2026-09-22 12:00 |
05:54:11.20 |
+14:06:30.2 |
HIP 27961 |
12.59 |
| 2026-09-23 00:00 |
05:54:11.13 |
+14:06:27.2 |
HIP 27961 |
12.63 |
| 2026-09-23 12:00 |
05:54:11.04 |
+14:06:24.3 |
HIP 27961 |
12.67 |
| 2026-09-24 00:00 |
05:54:10.95 |
+14:06:21.3 |
HIP 27961 |
12.72 |
| 2026-09-24 12:00 |
05:54:10.84 |
+14:06:18.4 |
HIP 27961 |
12.77 |
| 2026-09-25 00:00 |
05:54:10.73 |
+14:06:15.4 |
HIP 27961 |
12.82 |
| 2026-09-25 12:00 |
05:54:10.60 |
+14:06:12.4 |
HIP 27961 |
12.87 |
| 2026-09-26 00:00 |
05:54:10.47 |
+14:06:09.5 |
HIP 27961 |
12.93 |
| 2026-09-26 12:00 |
05:54:10.32 |
+14:06:06.5 |
HIP 27961 |
12.98 |
| 2026-09-27 00:00 |
05:54:10.16 |
+14:06:03.5 |
HIP 27961 |
13.04 |
| 2026-09-27 12:00 |
05:54:09.99 |
+14:06:00.6 |
HIP 27961 |
13.10 |
| 2026-09-28 00:00 |
05:54:09.81 |
+14:05:57.6 |
HIP 27961 |
13.17 |
| 2026-09-28 12:00 |
05:54:09.62 |
+14:05:54.6 |
HIP 27961 |
13.23 |
| 2026-09-29 00:00 |
05:54:09.42 |
+14:05:51.7 |
HIP 27961 |
13.30 |
| 2026-09-29 12:00 |
05:54:09.21 |
+14:05:48.7 |
HIP 27961 |
13.37 |
| 2026-09-30 00:00 |
05:54:08.99 |
+14:05:45.7 |
HIP 27961 |
13.44 |
| 2026-09-30 12:00 |
05:54:08.76 |
+14:05:42.8 |
HIP 27961 |
13.52 |
| 2026-10-01 00:00 |
05:54:08.52 |
+14:05:39.8 |
HIP 27961 |
13.59 |
| 2026-10-01 12:00 |
05:54:08.26 |
+14:05:36.9 |
HIP 27961 |
13.67 |
| 2026-10-02 00:00 |
05:54:08.00 |
+14:05:33.9 |
HIP 27961 |
13.75 |
| 2026-10-02 12:00 |
05:54:07.72 |
+14:05:31.0 |
HIP 27961 |
13.83 |
| 2026-10-03 00:00 |
05:54:07.44 |
+14:05:28.0 |
HIP 27961 |
13.92 |
| 2026-10-03 12:00 |
05:54:07.14 |
+14:05:25.1 |
HIP 27961 |
14.01 |
| 2026-10-04 00:00 |
05:54:06.83 |
+14:05:22.1 |
HIP 27961 |
14.10 |
| 2026-10-04 12:00 |
05:54:06.52 |
+14:05:19.2 |
HIP 27961 |
14.19 |
| 2026-10-05 00:00 |
05:54:06.19 |
+14:05:16.2 |
HIP 27961 |
14.28 |
| 2026-10-05 12:00 |
05:54:05.85 |
+14:05:13.3 |
HIP 27961 |
14.38 |
| 2026-10-06 00:00 |
05:54:05.50 |
+14:05:10.4 |
HIP 27961 |
14.47 |
| 2026-10-06 12:00 |
05:54:05.14 |
+14:05:07.4 |
HIP 27961 |
14.57 |
| 2026-10-07 00:00 |
05:54:04.77 |
+14:05:04.5 |
HIP 27961 |
14.67 |
| 2026-10-07 12:00 |
05:54:04.39 |
+14:05:01.6 |
HIP 27961 |
14.78 |
| 2026-10-08 00:00 |
05:54:04.00 |
+14:04:58.7 |
HIP 27961 |
14.88 |
| 2026-10-08 12:00 |
05:54:03.60 |
+14:04:55.8 |
HIP 27961 |
14.99 |
| 2026-10-09 00:00 |
05:54:03.18 |
+14:04:52.9 |
HIP 27961 |
15.10 |
| 2026-10-09 12:00 |
05:54:02.76 |
+14:04:50.0 |
HIP 27961 |
15.21 |
| 2026-10-10 00:00 |
05:54:02.33 |
+14:04:47.1 |
HIP 27961 |
15.33 |
| 2026-10-10 12:00 |
05:54:01.88 |
+14:04:44.2 |
HIP 27961 |
15.45 |
| 2026-10-11 00:00 |
05:54:01.43 |
+14:04:41.3 |
HIP 27961 |
15.56 |