| Parameter |
Value |
| Designation |
C/1931 O1 (Nagata) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1931-06-11T17:58:51.191040Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:03Z |
| Obs used |
33 |
| NEO |
- |
| M1 |
5.700 |
| K1 |
4.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1931-10-05.0000000 |
| e |
0.97845116 |
| q (au) |
1.046195 |
| a (au) |
48.549944 |
| i (deg) |
42.302413 |
| Ω (om, deg) |
192.252622 |
| ω (w, deg) |
320.091135 |
| M (ma, deg) |
0.335788 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.469 + 3.539\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.469 |
| n |
3.539 |
| gf |
0.994 |
| gb |
-0.700 |
| k |
0.800 |
| δ90 |
9.971 |
| 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 |
21:51:46.54 |
+17:19:47.1 |
HIP 107917 |
11.02 |
| 2026-07-29 12:00 |
21:51:45.25 |
+17:19:44.8 |
HIP 107917 |
11.01 |
| 2026-07-30 00:00 |
21:51:43.97 |
+17:19:42.4 |
HIP 107917 |
11.01 |
| 2026-07-30 12:00 |
21:51:42.68 |
+17:19:39.9 |
HIP 107917 |
11.01 |
| 2026-07-31 00:00 |
21:51:41.39 |
+17:19:37.3 |
HIP 107917 |
11.02 |
| 2026-07-31 12:00 |
21:51:40.09 |
+17:19:34.6 |
HIP 107917 |
11.04 |
| 2026-08-01 00:00 |
21:51:38.79 |
+17:19:31.7 |
HIP 107917 |
11.07 |
| 2026-08-01 12:00 |
21:51:37.49 |
+17:19:28.8 |
HIP 107917 |
11.10 |
| 2026-08-02 00:00 |
21:51:36.18 |
+17:19:25.8 |
HIP 107917 |
11.14 |
| 2026-08-02 12:00 |
21:51:34.87 |
+17:19:22.7 |
HIP 107917 |
11.19 |
| 2026-08-03 00:00 |
21:51:33.55 |
+17:19:19.5 |
HIP 107917 |
11.25 |
| 2026-08-03 12:00 |
21:51:32.24 |
+17:19:16.1 |
HIP 107917 |
11.31 |
| 2026-08-04 00:00 |
21:51:30.92 |
+17:19:12.7 |
HIP 107917 |
11.38 |
| 2026-08-04 12:00 |
21:51:29.59 |
+17:19:09.2 |
HIP 107917 |
11.46 |
| 2026-08-05 00:00 |
21:51:28.27 |
+17:19:05.5 |
HIP 107917 |
11.55 |
| 2026-08-05 12:00 |
21:51:26.94 |
+17:19:01.8 |
HIP 107917 |
11.64 |
| 2026-08-06 00:00 |
21:51:25.60 |
+17:18:58.0 |
HIP 107917 |
11.74 |
| 2026-08-06 12:00 |
21:51:24.27 |
+17:18:54.1 |
HIP 107917 |
11.85 |
| 2026-08-07 00:00 |
21:51:22.93 |
+17:18:50.0 |
HIP 107917 |
11.96 |
| 2026-08-07 12:00 |
21:51:21.59 |
+17:18:45.9 |
HIP 107917 |
12.08 |
| 2026-08-08 00:00 |
21:51:20.25 |
+17:18:41.7 |
HIP 107917 |
12.21 |
| 2026-08-08 12:00 |
21:51:18.91 |
+17:18:37.3 |
HIP 107917 |
12.34 |
| 2026-08-09 00:00 |
21:51:17.56 |
+17:18:32.9 |
HIP 107917 |
12.48 |
| 2026-08-09 12:00 |
21:51:16.21 |
+17:18:28.4 |
HIP 107917 |
12.63 |
| 2026-08-10 00:00 |
21:51:14.86 |
+17:18:23.8 |
HIP 107917 |
12.78 |
| 2026-08-10 12:00 |
21:51:13.51 |
+17:18:19.0 |
HIP 107917 |
12.94 |
| 2026-08-11 00:00 |
21:51:12.15 |
+17:18:14.2 |
HIP 107917 |
13.10 |
| 2026-08-11 12:00 |
21:51:10.80 |
+17:18:09.3 |
HIP 107917 |
13.27 |
| 2026-08-12 00:00 |
21:51:09.44 |
+17:18:04.3 |
HIP 107917 |
13.44 |
| 2026-08-12 12:00 |
21:51:08.08 |
+17:17:59.2 |
HIP 107917 |
13.62 |
| 2026-08-13 00:00 |
21:51:06.72 |
+17:17:53.9 |
HIP 107917 |
13.81 |
| 2026-08-13 12:00 |
21:51:05.36 |
+17:17:48.6 |
HIP 107788 |
13.55 |
| 2026-08-14 00:00 |
21:51:04.00 |
+17:17:43.2 |
HIP 107788 |
13.23 |
| 2026-08-14 12:00 |
21:51:02.64 |
+17:17:37.7 |
HIP 107788 |
12.90 |
| 2026-08-15 00:00 |
21:51:01.27 |
+17:17:32.1 |
HIP 107788 |
12.57 |
| 2026-08-15 12:00 |
21:50:59.91 |
+17:17:26.4 |
HIP 107788 |
12.24 |
| 2026-08-16 00:00 |
21:50:58.54 |
+17:17:20.6 |
HIP 107788 |
11.91 |
| 2026-08-16 12:00 |
21:50:57.18 |
+17:17:14.8 |
HIP 107788 |
11.59 |
| 2026-08-17 00:00 |
21:50:55.81 |
+17:17:08.8 |
HIP 107788 |
11.26 |
| 2026-08-17 12:00 |
21:50:54.44 |
+17:17:02.7 |
HIP 107788 |
10.93 |
| 2026-08-18 00:00 |
21:50:53.08 |
+17:16:56.6 |
HIP 107788 |
10.61 |
| 2026-08-18 12:00 |
21:50:51.71 |
+17:16:50.3 |
HIP 107788 |
10.29 |
| 2026-08-19 00:00 |
21:50:50.34 |
+17:16:44.0 |
HIP 107788 |
9.96 |