| Parameter |
Value |
| Designation |
C/1988 Y1 (Yanaka) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1988-12-11T15:40:33.395520Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:36Z |
| Obs used |
56 |
| NEO |
- |
| M1 |
12.800 |
| K1 |
15.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1989-01-12.0000000 |
| e |
1.00000000 |
| q (au) |
0.427814 |
| a (au) |
- |
| i (deg) |
71.010955 |
| Ω (om, deg) |
315.523025 |
| ω (w, deg) |
88.122151 |
| M (ma, deg) |
- |
Magnitude
Scatter + Global Linear
$$
M_a = (13.086 + 5.655\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.086 |
| n |
5.655 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
1.000 |
| δ90 |
1.000 |
| 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) |
| 2026-06-01 00:00 |
09:19:47.62 |
-62:02:49.2 |
HIP 45817 |
6.12 |
| 2026-06-01 12:00 |
09:19:49.08 |
-62:02:24.9 |
HIP 45817 |
5.76 |
| 2026-06-02 00:00 |
09:19:50.58 |
-62:02:00.7 |
HIP 45817 |
5.42 |
| 2026-06-02 12:00 |
09:19:52.10 |
-62:01:36.6 |
HIP 45817 |
5.09 |
| 2026-06-03 00:00 |
09:19:53.66 |
-62:01:12.7 |
HIP 45817 |
4.77 |
| 2026-06-03 12:00 |
09:19:55.24 |
-62:00:48.8 |
HIP 45817 |
4.47 |
| 2026-06-04 00:00 |
09:19:56.85 |
-62:00:25.1 |
HIP 45817 |
4.19 |
| 2026-06-04 12:00 |
09:19:58.49 |
-62:00:01.4 |
HIP 45817 |
3.94 |
| 2026-06-05 00:00 |
09:20:00.15 |
-61:59:37.9 |
HIP 45817 |
3.72 |
| 2026-06-05 12:00 |
09:20:01.85 |
-61:59:14.5 |
HIP 45817 |
3.54 |
| 2026-06-06 00:00 |
09:20:03.57 |
-61:58:51.3 |
HIP 45817 |
3.40 |
| 2026-06-06 12:00 |
09:20:05.32 |
-61:58:28.1 |
HIP 45817 |
3.31 |
| 2026-06-07 00:00 |
09:20:07.10 |
-61:58:05.1 |
HIP 45817 |
3.27 |
| 2026-06-07 12:00 |
09:20:08.90 |
-61:57:42.2 |
HIP 45817 |
3.29 |
| 2026-06-08 00:00 |
09:20:10.73 |
-61:57:19.4 |
HIP 45817 |
3.36 |
| 2026-06-08 12:00 |
09:20:12.59 |
-61:56:56.8 |
HIP 45817 |
3.48 |
| 2026-06-09 00:00 |
09:20:14.48 |
-61:56:34.2 |
HIP 45817 |
3.64 |
| 2026-06-09 12:00 |
09:20:16.39 |
-61:56:11.9 |
HIP 45817 |
3.84 |
| 2026-06-10 00:00 |
09:20:18.33 |
-61:55:49.6 |
HIP 45817 |
4.08 |
| 2026-06-10 12:00 |
09:20:20.30 |
-61:55:27.5 |
HIP 45817 |
4.34 |
| 2026-06-11 00:00 |
09:20:22.29 |
-61:55:05.5 |
HIP 45817 |
4.63 |
| 2026-06-11 12:00 |
09:20:24.31 |
-61:54:43.7 |
HIP 45817 |
4.94 |
| 2026-06-12 00:00 |
09:20:26.35 |
-61:54:22.0 |
HIP 45817 |
5.26 |
| 2026-06-12 12:00 |
09:20:28.42 |
-61:54:00.4 |
HIP 45817 |
5.59 |
| 2026-06-13 00:00 |
09:20:30.52 |
-61:53:39.0 |
HIP 45817 |
5.94 |
| 2026-06-13 12:00 |
09:20:32.64 |
-61:53:17.7 |
HIP 45817 |
6.29 |
| 2026-06-14 00:00 |
09:20:34.79 |
-61:52:56.6 |
HIP 45817 |
6.65 |
| 2026-06-14 12:00 |
09:20:36.97 |
-61:52:35.6 |
HIP 45817 |
7.02 |
| 2026-06-15 00:00 |
09:20:39.16 |
-61:52:14.7 |
HIP 45817 |
7.39 |
| 2026-06-15 12:00 |
09:20:41.39 |
-61:51:54.0 |
HIP 45817 |
7.76 |
| 2026-06-16 00:00 |
09:20:43.64 |
-61:51:33.5 |
HIP 45817 |
8.14 |
| 2026-06-16 12:00 |
09:20:45.91 |
-61:51:13.1 |
HIP 45817 |
8.53 |
| 2026-06-17 00:00 |
09:20:48.21 |
-61:50:52.9 |
HIP 45817 |
8.91 |
| 2026-06-17 12:00 |
09:20:50.53 |
-61:50:32.8 |
HIP 45817 |
9.30 |
| 2026-06-18 00:00 |
09:20:52.87 |
-61:50:12.9 |
HIP 45817 |
9.69 |
| 2026-06-18 12:00 |
09:20:55.24 |
-61:49:53.2 |
HIP 45817 |
10.08 |
| 2026-06-19 00:00 |
09:20:57.64 |
-61:49:33.6 |
HIP 45817 |
10.47 |
| 2026-06-19 12:00 |
09:21:00.05 |
-61:49:14.2 |
HIP 45817 |
10.87 |
| 2026-06-20 00:00 |
09:21:02.49 |
-61:48:54.9 |
HIP 45817 |
11.26 |
| 2026-06-20 12:00 |
09:21:04.96 |
-61:48:35.8 |
HIP 45817 |
11.66 |
| 2026-06-21 00:00 |
09:21:07.44 |
-61:48:16.9 |
HIP 45817 |
12.05 |
| 2026-06-21 12:00 |
09:21:09.95 |
-61:47:58.1 |
HIP 45817 |
12.45 |
| 2026-06-22 00:00 |
09:21:12.48 |
-61:47:39.5 |
HIP 45817 |
12.85 |