| Parameter |
Value |
| Designation |
70P/Kojima |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2014-10-20T16:03:22.438080Z |
| Orbit solution date (soln_date, UTC) |
2026-03-31T13:31:05Z |
| Obs used |
2095 |
| NEO |
- |
| M1 |
12.400 |
| K1 |
11.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-05-10.0000000 |
| e |
0.45391804 |
| q (au) |
2.006571 |
| a (au) |
3.674486 |
| i (deg) |
6.600120 |
| Ω (om, deg) |
119.270193 |
| ω (w, deg) |
1.954017 |
| M (ma, deg) |
28.172138 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.329 + 5.287\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.329 |
| n |
5.287 |
| gf |
1.000 |
| gb |
-0.745 |
| k |
0.994 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2020-09-09 |
2021-09-27 |
-4.6159 |
+1.433 |
| 2021-09-27 |
2022-06-17 |
+13.1079 |
-6.435 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
21:59:39.08 |
-14:27:08.9 |
HIP 108529 |
7.73 |
| 2026-03-26 12:00 |
22:00:01.76 |
-14:25:26.0 |
HIP 108529 |
13.44 |
| 2026-03-27 00:00 |
22:00:24.37 |
-14:23:43.4 |
HIP 108649 |
14.30 |
| 2026-03-27 12:00 |
22:00:46.92 |
-14:22:01.1 |
HIP 108722 |
10.03 |
| 2026-03-28 00:00 |
22:01:09.41 |
-14:20:19.1 |
HIP 108722 |
4.35 |
| 2026-03-28 12:00 |
22:01:31.82 |
-14:18:37.4 |
HIP 108722 |
1.51 |
| 2026-03-29 00:00 |
22:01:54.17 |
-14:16:56.1 |
HIP 108722 |
7.08 |
| 2026-03-29 12:00 |
22:02:16.45 |
-14:15:15.0 |
HIP 108722 |
12.72 |
| 2026-03-30 00:00 |
22:02:38.66 |
-14:13:34.3 |
HIP 108722 |
18.36 |
| 2026-03-30 12:00 |
22:03:00.80 |
-14:11:53.9 |
HIP 108722 |
23.97 |
| 2026-03-31 00:00 |
22:03:22.87 |
-14:10:13.9 |
HIP 108958 |
22.87 |
| 2026-03-31 12:00 |
22:03:44.88 |
-14:08:34.1 |
HIP 108958 |
21.01 |
| 2026-04-01 00:00 |
22:04:06.81 |
-14:06:54.8 |
HIP 108958 |
20.55 |
| 2026-04-01 12:00 |
22:04:28.67 |
-14:05:15.7 |
HIP 108958 |
21.56 |
| 2026-04-02 00:00 |
22:04:50.45 |
-14:03:37.1 |
HIP 109051 |
20.01 |
| 2026-04-02 12:00 |
22:05:12.17 |
-14:01:58.8 |
HIP 109051 |
16.43 |
| 2026-04-03 00:00 |
22:05:33.81 |
-14:00:20.8 |
HIP 109140 |
14.12 |
| 2026-04-03 12:00 |
22:05:55.37 |
-13:58:43.3 |
HIP 109139 |
9.94 |
| 2026-04-04 00:00 |
22:06:16.86 |
-13:57:06.1 |
HIP 109139 |
5.43 |
| 2026-04-04 12:00 |
22:06:38.28 |
-13:55:29.3 |
HIP 109139 |
4.42 |
| 2026-04-05 00:00 |
22:06:59.62 |
-13:53:52.8 |
HIP 109139 |
8.29 |
| 2026-04-05 12:00 |
22:07:20.88 |
-13:52:16.8 |
HIP 109139 |
13.27 |
| 2026-04-06 00:00 |
22:07:42.07 |
-13:50:41.2 |
HIP 109139 |
18.47 |
| 2026-04-06 12:00 |
22:08:03.18 |
-13:49:05.9 |
HIP 109139 |
23.74 |
| 2026-04-07 00:00 |
22:08:24.21 |
-13:47:31.1 |
HIP 109395 |
20.49 |
| 2026-04-07 12:00 |
22:08:45.16 |
-13:45:56.7 |
HIP 109395 |
16.36 |
| 2026-04-08 00:00 |
22:09:06.03 |
-13:44:22.7 |
HIP 109390 |
11.80 |
| 2026-04-08 12:00 |
22:09:26.82 |
-13:42:49.2 |
HIP 109390 |
7.42 |
| 2026-04-09 00:00 |
22:09:47.52 |
-13:41:16.0 |
HIP 109390 |
5.17 |
| 2026-04-09 12:00 |
22:10:08.15 |
-13:39:43.3 |
HIP 109390 |
7.32 |
| 2026-04-10 00:00 |
22:10:28.69 |
-13:38:11.1 |
HIP 109390 |
11.62 |
| 2026-04-10 12:00 |
22:10:49.15 |
-13:36:39.3 |
HIP 109390 |
16.45 |
| 2026-04-11 00:00 |
22:11:09.52 |
-13:35:08.0 |
HIP 109390 |
21.43 |
| 2026-04-11 12:00 |
22:11:29.81 |
-13:33:37.1 |
HIP 109390 |
26.46 |
| 2026-04-12 00:00 |
22:11:50.01 |
-13:32:06.7 |
HIP 109683 |
27.36 |
| 2026-04-12 12:00 |
22:12:10.13 |
-13:30:36.8 |
HIP 109683 |
25.58 |
| 2026-04-13 00:00 |
22:12:30.16 |
-13:29:07.4 |
HIP 109683 |
24.74 |
| 2026-04-13 12:00 |
22:12:50.10 |
-13:27:38.5 |
HIP 109683 |
24.93 |
| 2026-04-14 00:00 |
22:13:09.95 |
-13:26:10.0 |
HIP 109672 |
24.59 |
| 2026-04-14 12:00 |
22:13:29.71 |
-13:24:42.1 |
HIP 109672 |
24.09 |
| 2026-04-15 00:00 |
22:13:49.37 |
-13:23:14.7 |
HIP 109672 |
24.62 |
| 2026-04-15 12:00 |
22:14:08.95 |
-13:21:47.7 |
HIP 109672 |
26.11 |
| 2026-04-16 00:00 |
22:14:28.44 |
-13:20:21.4 |
HIP 109672 |
28.40 |