| Parameter |
Value |
| Designation |
98P/Takamizawa |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2013-08-05T11:26:09.798720Z |
| Orbit solution date (soln_date, UTC) |
2021-06-02T08:41:36Z |
| Obs used |
558 |
| NEO |
- |
| M1 |
14.600 |
| K1 |
8.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2011-12-20.0000000 |
| e |
0.56058596 |
| q (au) |
1.672338 |
| a (au) |
3.805837 |
| i (deg) |
10.545980 |
| Ω (om, deg) |
114.752675 |
| ω (w, deg) |
157.947415 |
| M (ma, deg) |
281.084281 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.094 + 5.937\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.094 |
| n |
5.937 |
| gf |
1.000 |
| gb |
-0.737 |
| 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) |
| 2026-05-12 00:00 |
07:37:24.48 |
+23:00:32.1 |
HIP 36898 |
30.72 |
| 2026-05-12 12:00 |
07:37:41.69 |
+23:00:04.5 |
HIP 36898 |
34.70 |
| 2026-05-13 00:00 |
07:37:59.04 |
+22:59:36.5 |
HIP 36898 |
38.72 |
| 2026-05-13 12:00 |
07:38:16.52 |
+22:59:08.1 |
HIP 37428 |
37.33 |
| 2026-05-14 00:00 |
07:38:34.14 |
+22:58:39.2 |
HIP 37428 |
33.32 |
| 2026-05-14 12:00 |
07:38:51.88 |
+22:58:09.9 |
HIP 37428 |
29.29 |
| 2026-05-15 00:00 |
07:39:09.76 |
+22:57:40.2 |
HIP 37428 |
25.27 |
| 2026-05-15 12:00 |
07:39:27.77 |
+22:57:10.0 |
HIP 37428 |
21.26 |
| 2026-05-16 00:00 |
07:39:45.90 |
+22:56:39.4 |
HIP 37428 |
17.30 |
| 2026-05-16 12:00 |
07:40:04.17 |
+22:56:08.4 |
HIP 37428 |
13.46 |
| 2026-05-17 00:00 |
07:40:22.56 |
+22:55:36.9 |
HIP 37428 |
9.94 |
| 2026-05-17 12:00 |
07:40:41.08 |
+22:55:05.1 |
HIP 37428 |
7.24 |
| 2026-05-18 00:00 |
07:40:59.72 |
+22:54:32.8 |
HIP 37428 |
6.57 |
| 2026-05-18 12:00 |
07:41:18.48 |
+22:54:00.0 |
HIP 37428 |
8.47 |
| 2026-05-19 00:00 |
07:41:37.37 |
+22:53:26.9 |
HIP 37522 |
6.78 |
| 2026-05-19 12:00 |
07:41:56.38 |
+22:52:53.3 |
HIP 37522 |
3.48 |
| 2026-05-20 00:00 |
07:42:15.51 |
+22:52:19.3 |
HIP 37522 |
4.17 |
| 2026-05-20 12:00 |
07:42:34.76 |
+22:51:44.9 |
HIP 37522 |
7.91 |
| 2026-05-21 00:00 |
07:42:54.13 |
+22:51:10.0 |
HIP 37522 |
12.19 |
| 2026-05-21 12:00 |
07:43:13.62 |
+22:50:34.7 |
HIP 37522 |
16.61 |
| 2026-05-22 00:00 |
07:43:33.22 |
+22:49:59.0 |
HIP 37522 |
21.10 |
| 2026-05-22 12:00 |
07:43:52.93 |
+22:49:22.9 |
HIP 37799 |
19.78 |
| 2026-05-23 00:00 |
07:44:12.76 |
+22:48:46.4 |
HIP 37799 |
16.79 |
| 2026-05-23 12:00 |
07:44:32.71 |
+22:48:09.4 |
HIP 37799 |
14.65 |
| 2026-05-24 00:00 |
07:44:52.76 |
+22:47:32.0 |
HIP 37799 |
13.80 |
| 2026-05-24 12:00 |
07:45:12.93 |
+22:46:54.2 |
HIP 37799 |
14.50 |
| 2026-05-25 00:00 |
07:45:33.20 |
+22:46:16.0 |
HIP 37799 |
16.56 |
| 2026-05-25 12:00 |
07:45:53.59 |
+22:45:37.4 |
HIP 37799 |
19.59 |
| 2026-05-26 00:00 |
07:46:14.08 |
+22:44:58.3 |
HIP 37799 |
23.22 |
| 2026-05-26 12:00 |
07:46:34.68 |
+22:44:18.9 |
HIP 37799 |
27.22 |
| 2026-05-27 00:00 |
07:46:55.38 |
+22:43:39.0 |
HIP 38019 |
26.86 |
| 2026-05-27 12:00 |
07:47:16.19 |
+22:42:58.7 |
HIP 38019 |
26.46 |
| 2026-05-28 00:00 |
07:47:37.11 |
+22:42:18.0 |
HIP 38019 |
26.94 |
| 2026-05-28 12:00 |
07:47:58.12 |
+22:41:36.8 |
HIP 38106 |
28.06 |
| 2026-05-29 00:00 |
07:48:19.24 |
+22:40:55.3 |
HIP 38247 |
24.99 |
| 2026-05-29 12:00 |
07:48:40.46 |
+22:40:13.3 |
HIP 38247 |
20.26 |
| 2026-05-30 00:00 |
07:49:01.78 |
+22:39:30.9 |
HIP 38247 |
15.63 |
| 2026-05-30 12:00 |
07:49:23.20 |
+22:38:48.1 |
HIP 38247 |
11.28 |
| 2026-05-31 00:00 |
07:49:44.72 |
+22:38:04.9 |
HIP 38247 |
7.74 |
| 2026-05-31 12:00 |
07:50:06.34 |
+22:37:21.3 |
HIP 38247 |
6.55 |
| 2026-06-01 00:00 |
07:50:28.06 |
+22:36:37.3 |
HIP 38247 |
8.78 |
| 2026-06-01 12:00 |
07:50:49.87 |
+22:35:52.8 |
HIP 38247 |
12.77 |
| 2026-06-02 00:00 |
07:51:11.78 |
+22:35:08.0 |
HIP 38247 |
17.36 |