| Parameter |
Value |
| Designation |
C/1992 F1 (Tanaka-Machholz) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1992-04-22T16:35:26.859840Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:41Z |
| Obs used |
167 |
| NEO |
- |
| M1 |
5.600 |
| K1 |
19.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1992-05-25.0000000 |
| e |
0.99597703 |
| q (au) |
1.261503 |
| a (au) |
313.574953 |
| i (deg) |
79.292423 |
| Ω (om, deg) |
300.508310 |
| ω (w, deg) |
65.475657 |
| M (ma, deg) |
0.005735 |
Magnitude
Scatter + Global Linear
$$
M_a = (4.541 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
4.541 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| k |
1.000 |
| 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 |
08:00:47.21 |
-28:36:58.9 |
HIP 39086 |
15.13 |
| 2026-05-12 12:00 |
08:00:48.09 |
-28:36:39.6 |
HIP 39086 |
15.45 |
| 2026-05-13 00:00 |
08:00:48.98 |
-28:36:20.6 |
HIP 39086 |
15.77 |
| 2026-05-13 12:00 |
08:00:49.90 |
-28:36:01.6 |
HIP 39086 |
16.10 |
| 2026-05-14 00:00 |
08:00:50.83 |
-28:35:42.7 |
HIP 39086 |
16.44 |
| 2026-05-14 12:00 |
08:00:51.78 |
-28:35:24.0 |
HIP 39269 |
16.70 |
| 2026-05-15 00:00 |
08:00:52.75 |
-28:35:05.4 |
HIP 39269 |
16.33 |
| 2026-05-15 12:00 |
08:00:53.73 |
-28:34:46.9 |
HIP 39269 |
15.97 |
| 2026-05-16 00:00 |
08:00:54.73 |
-28:34:28.5 |
HIP 39269 |
15.61 |
| 2026-05-16 12:00 |
08:00:55.75 |
-28:34:10.2 |
HIP 39269 |
15.24 |
| 2026-05-17 00:00 |
08:00:56.79 |
-28:33:52.1 |
HIP 39269 |
14.87 |
| 2026-05-17 12:00 |
08:00:57.84 |
-28:33:34.1 |
HIP 39269 |
14.50 |
| 2026-05-18 00:00 |
08:00:58.91 |
-28:33:16.3 |
HIP 39269 |
14.13 |
| 2026-05-18 12:00 |
08:01:00.00 |
-28:32:58.5 |
HIP 39269 |
13.76 |
| 2026-05-19 00:00 |
08:01:01.10 |
-28:32:40.9 |
HIP 39269 |
13.39 |
| 2026-05-19 12:00 |
08:01:02.22 |
-28:32:23.4 |
HIP 39269 |
13.02 |
| 2026-05-20 00:00 |
08:01:03.36 |
-28:32:06.1 |
HIP 39269 |
12.65 |
| 2026-05-20 12:00 |
08:01:04.51 |
-28:31:48.9 |
HIP 39269 |
12.27 |
| 2026-05-21 00:00 |
08:01:05.68 |
-28:31:31.8 |
HIP 39269 |
11.90 |
| 2026-05-21 12:00 |
08:01:06.86 |
-28:31:14.9 |
HIP 39269 |
11.52 |
| 2026-05-22 00:00 |
08:01:08.06 |
-28:30:58.1 |
HIP 39269 |
11.14 |
| 2026-05-22 12:00 |
08:01:09.28 |
-28:30:41.5 |
HIP 39269 |
10.76 |
| 2026-05-23 00:00 |
08:01:10.52 |
-28:30:24.9 |
HIP 39269 |
10.38 |
| 2026-05-23 12:00 |
08:01:11.76 |
-28:30:08.6 |
HIP 39269 |
10.00 |
| 2026-05-24 00:00 |
08:01:13.03 |
-28:29:52.3 |
HIP 39269 |
9.62 |
| 2026-05-24 12:00 |
08:01:14.31 |
-28:29:36.3 |
HIP 39269 |
9.24 |
| 2026-05-25 00:00 |
08:01:15.61 |
-28:29:20.3 |
HIP 39269 |
8.85 |
| 2026-05-25 12:00 |
08:01:16.92 |
-28:29:04.5 |
HIP 39269 |
8.47 |
| 2026-05-26 00:00 |
08:01:18.24 |
-28:28:48.9 |
HIP 39269 |
8.08 |
| 2026-05-26 12:00 |
08:01:19.59 |
-28:28:33.4 |
HIP 39269 |
7.69 |
| 2026-05-27 00:00 |
08:01:20.94 |
-28:28:18.0 |
HIP 39269 |
7.31 |
| 2026-05-27 12:00 |
08:01:22.31 |
-28:28:02.8 |
HIP 39269 |
6.92 |
| 2026-05-28 00:00 |
08:01:23.70 |
-28:27:47.8 |
HIP 39269 |
6.53 |
| 2026-05-28 12:00 |
08:01:25.10 |
-28:27:32.9 |
HIP 39269 |
6.14 |
| 2026-05-29 00:00 |
08:01:26.52 |
-28:27:18.1 |
HIP 39269 |
5.74 |
| 2026-05-29 12:00 |
08:01:27.95 |
-28:27:03.5 |
HIP 39269 |
5.35 |
| 2026-05-30 00:00 |
08:01:29.39 |
-28:26:49.1 |
HIP 39269 |
4.96 |
| 2026-05-30 12:00 |
08:01:30.85 |
-28:26:34.8 |
HIP 39269 |
4.56 |
| 2026-05-31 00:00 |
08:01:32.32 |
-28:26:20.6 |
HIP 39269 |
4.17 |
| 2026-05-31 12:00 |
08:01:33.81 |
-28:26:06.7 |
HIP 39269 |
3.77 |
| 2026-06-01 00:00 |
08:01:35.31 |
-28:25:52.8 |
HIP 39269 |
3.37 |
| 2026-06-01 12:00 |
08:01:36.83 |
-28:25:39.2 |
HIP 39269 |
2.98 |
| 2026-06-02 00:00 |
08:01:38.36 |
-28:25:25.7 |
HIP 39269 |
2.58 |