| 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 |
9.978 |
| 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) |
| 2026-03-26 00:00 |
21:52:25.78 |
+16:47:58.1 |
HIP 107917 |
22.50 |
| 2026-03-26 12:00 |
21:52:26.89 |
+16:48:09.4 |
HIP 107917 |
22.43 |
| 2026-03-27 00:00 |
21:52:27.99 |
+16:48:20.7 |
HIP 107917 |
22.36 |
| 2026-03-27 12:00 |
21:52:29.08 |
+16:48:32.0 |
HIP 107917 |
22.30 |
| 2026-03-28 00:00 |
21:52:30.17 |
+16:48:43.4 |
HIP 107917 |
22.23 |
| 2026-03-28 12:00 |
21:52:31.24 |
+16:48:54.8 |
HIP 107917 |
22.18 |
| 2026-03-29 00:00 |
21:52:32.31 |
+16:49:06.3 |
HIP 107917 |
22.12 |
| 2026-03-29 12:00 |
21:52:33.37 |
+16:49:17.8 |
HIP 107917 |
22.07 |
| 2026-03-30 00:00 |
21:52:34.42 |
+16:49:29.3 |
HIP 107917 |
22.02 |
| 2026-03-30 12:00 |
21:52:35.47 |
+16:49:40.8 |
HIP 107917 |
21.97 |
| 2026-03-31 00:00 |
21:52:36.50 |
+16:49:52.4 |
HIP 107917 |
21.93 |
| 2026-03-31 12:00 |
21:52:37.53 |
+16:50:04.0 |
HIP 107917 |
21.89 |
| 2026-04-01 00:00 |
21:52:38.55 |
+16:50:15.6 |
HIP 107917 |
21.85 |
| 2026-04-01 12:00 |
21:52:39.56 |
+16:50:27.2 |
HIP 108100 |
21.69 |
| 2026-04-02 00:00 |
21:52:40.57 |
+16:50:38.9 |
HIP 108100 |
21.44 |
| 2026-04-02 12:00 |
21:52:41.56 |
+16:50:50.6 |
HIP 108100 |
21.19 |
| 2026-04-03 00:00 |
21:52:42.55 |
+16:51:02.3 |
HIP 108100 |
20.95 |
| 2026-04-03 12:00 |
21:52:43.53 |
+16:51:14.1 |
HIP 108100 |
20.70 |
| 2026-04-04 00:00 |
21:52:44.50 |
+16:51:25.8 |
HIP 108100 |
20.47 |
| 2026-04-04 12:00 |
21:52:45.46 |
+16:51:37.6 |
HIP 108100 |
20.23 |
| 2026-04-05 00:00 |
21:52:46.41 |
+16:51:49.5 |
HIP 108100 |
20.00 |
| 2026-04-05 12:00 |
21:52:47.35 |
+16:52:01.3 |
HIP 108100 |
19.78 |
| 2026-04-06 00:00 |
21:52:48.29 |
+16:52:13.1 |
HIP 108100 |
19.56 |
| 2026-04-06 12:00 |
21:52:49.21 |
+16:52:25.0 |
HIP 108100 |
19.34 |
| 2026-04-07 00:00 |
21:52:50.13 |
+16:52:36.9 |
HIP 108100 |
19.12 |
| 2026-04-07 12:00 |
21:52:51.04 |
+16:52:48.8 |
HIP 108100 |
18.92 |
| 2026-04-08 00:00 |
21:52:51.94 |
+16:53:00.7 |
HIP 108100 |
18.71 |
| 2026-04-08 12:00 |
21:52:52.83 |
+16:53:12.6 |
HIP 108100 |
18.51 |
| 2026-04-09 00:00 |
21:52:53.71 |
+16:53:24.6 |
HIP 108100 |
18.32 |
| 2026-04-09 12:00 |
21:52:54.58 |
+16:53:36.6 |
HIP 108100 |
18.13 |
| 2026-04-10 00:00 |
21:52:55.44 |
+16:53:48.5 |
HIP 108100 |
17.94 |
| 2026-04-10 12:00 |
21:52:56.29 |
+16:54:00.5 |
HIP 108100 |
17.76 |
| 2026-04-11 00:00 |
21:52:57.14 |
+16:54:12.5 |
HIP 108100 |
17.58 |
| 2026-04-11 12:00 |
21:52:57.97 |
+16:54:24.5 |
HIP 108100 |
17.41 |
| 2026-04-12 00:00 |
21:52:58.79 |
+16:54:36.5 |
HIP 108100 |
17.25 |
| 2026-04-12 12:00 |
21:52:59.61 |
+16:54:48.6 |
HIP 108100 |
17.09 |
| 2026-04-13 00:00 |
21:53:00.41 |
+16:55:00.6 |
HIP 108100 |
16.93 |
| 2026-04-13 12:00 |
21:53:01.21 |
+16:55:12.6 |
HIP 108100 |
16.78 |
| 2026-04-14 00:00 |
21:53:01.99 |
+16:55:24.7 |
HIP 108100 |
16.64 |
| 2026-04-14 12:00 |
21:53:02.77 |
+16:55:36.7 |
HIP 108100 |
16.50 |
| 2026-04-15 00:00 |
21:53:03.53 |
+16:55:48.8 |
HIP 108100 |
16.37 |
| 2026-04-15 12:00 |
21:53:04.29 |
+16:56:00.9 |
HIP 108100 |
16.25 |
| 2026-04-16 00:00 |
21:53:05.03 |
+16:56:12.9 |
HIP 108100 |
16.12 |