| Parameter |
Value |
| Designation |
85D/Boethin |
| Type |
D |
| Perihelion (tp_cal, UTC) |
2008-12-12T17:55:03.103680Z |
| Orbit solution date (soln_date, UTC) |
2007-09-25T13:47:46Z |
| Obs used |
51 |
| NEO |
Yes |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2007-06-01.0000000 |
| e |
0.78116063 |
| q (au) |
1.134657 |
| a (au) |
5.184887 |
| i (deg) |
4.295295 |
| Ω (om, deg) |
359.396114 |
| ω (w, deg) |
37.618385 |
| M (ma, deg) |
313.187511 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.705 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.705 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.865 |
| k |
1.000 |
| δ90 |
9.984 |
| 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 |
14:33:11.69 |
-19:25:24.6 |
HIP 71242 |
14.84 |
| 2026-03-26 12:00 |
14:33:02.18 |
-19:24:51.4 |
HIP 71242 |
17.12 |
| 2026-03-27 00:00 |
14:32:52.58 |
-19:24:17.7 |
HIP 71242 |
19.44 |
| 2026-03-27 12:00 |
14:32:42.90 |
-19:23:43.4 |
HIP 71242 |
21.78 |
| 2026-03-28 00:00 |
14:32:33.14 |
-19:23:08.6 |
HIP 71242 |
24.14 |
| 2026-03-28 12:00 |
14:32:23.30 |
-19:22:33.3 |
HIP 71242 |
26.52 |
| 2026-03-29 00:00 |
14:32:13.38 |
-19:21:57.5 |
HIP 71242 |
28.93 |
| 2026-03-29 12:00 |
14:32:03.38 |
-19:21:21.2 |
HIP 71242 |
31.36 |
| 2026-03-30 00:00 |
14:31:53.31 |
-19:20:44.4 |
HIP 70889 |
31.42 |
| 2026-03-30 12:00 |
14:31:43.16 |
-19:20:07.1 |
HIP 70889 |
28.96 |
| 2026-03-31 00:00 |
14:31:32.93 |
-19:19:29.2 |
HIP 70889 |
26.47 |
| 2026-03-31 12:00 |
14:31:22.63 |
-19:18:50.9 |
HIP 70889 |
23.97 |
| 2026-04-01 00:00 |
14:31:12.26 |
-19:18:12.1 |
HIP 70889 |
21.45 |
| 2026-04-01 12:00 |
14:31:01.82 |
-19:17:32.7 |
HIP 70889 |
18.91 |
| 2026-04-02 00:00 |
14:30:51.31 |
-19:16:52.9 |
HIP 70889 |
16.36 |
| 2026-04-02 12:00 |
14:30:40.72 |
-19:16:12.6 |
HIP 70889 |
13.80 |
| 2026-04-03 00:00 |
14:30:30.07 |
-19:15:31.8 |
HIP 70889 |
11.23 |
| 2026-04-03 12:00 |
14:30:19.36 |
-19:14:50.6 |
HIP 70889 |
8.67 |
| 2026-04-04 00:00 |
14:30:08.57 |
-19:14:08.8 |
HIP 70889 |
6.13 |
| 2026-04-04 12:00 |
14:29:57.73 |
-19:13:26.6 |
HIP 70889 |
3.73 |
| 2026-04-05 00:00 |
14:29:46.81 |
-19:12:43.9 |
HIP 70889 |
2.08 |
| 2026-04-05 12:00 |
14:29:35.84 |
-19:12:00.7 |
HIP 70889 |
3.00 |
| 2026-04-06 00:00 |
14:29:24.80 |
-19:11:17.1 |
HIP 70889 |
5.32 |
| 2026-04-06 12:00 |
14:29:13.71 |
-19:10:33.0 |
HIP 70889 |
7.91 |
| 2026-04-07 00:00 |
14:29:02.55 |
-19:09:48.5 |
HIP 70889 |
10.58 |
| 2026-04-07 12:00 |
14:28:51.34 |
-19:09:03.5 |
HIP 70889 |
13.29 |
| 2026-04-08 00:00 |
14:28:40.07 |
-19:08:18.1 |
HIP 70889 |
16.03 |
| 2026-04-08 12:00 |
14:28:28.75 |
-19:07:32.2 |
HIP 70889 |
18.79 |
| 2026-04-09 00:00 |
14:28:17.37 |
-19:06:45.9 |
HIP 70889 |
21.57 |
| 2026-04-09 12:00 |
14:28:05.94 |
-19:05:59.2 |
HIP 70889 |
24.37 |
| 2026-04-10 00:00 |
14:27:54.45 |
-19:05:12.0 |
HIP 70608 |
24.71 |
| 2026-04-10 12:00 |
14:27:42.92 |
-19:04:24.4 |
HIP 70608 |
22.15 |
| 2026-04-11 00:00 |
14:27:31.34 |
-19:03:36.3 |
HIP 70608 |
19.65 |
| 2026-04-11 12:00 |
14:27:19.71 |
-19:02:47.9 |
HIP 70608 |
17.25 |
| 2026-04-12 00:00 |
14:27:08.03 |
-19:01:59.1 |
HIP 70608 |
15.00 |
| 2026-04-12 12:00 |
14:26:56.31 |
-19:01:09.8 |
HIP 70608 |
12.99 |
| 2026-04-13 00:00 |
14:26:44.54 |
-19:00:20.1 |
HIP 70608 |
11.37 |
| 2026-04-13 12:00 |
14:26:32.73 |
-18:59:30.1 |
HIP 70608 |
10.31 |
| 2026-04-14 00:00 |
14:26:20.89 |
-18:58:39.6 |
HIP 70608 |
10.01 |
| 2026-04-14 12:00 |
14:26:09.00 |
-18:57:48.8 |
HIP 70608 |
10.56 |
| 2026-04-15 00:00 |
14:25:57.07 |
-18:56:57.6 |
HIP 70608 |
11.83 |
| 2026-04-15 12:00 |
14:25:45.11 |
-18:56:06.0 |
HIP 70608 |
13.63 |
| 2026-04-16 00:00 |
14:25:33.11 |
-18:55:14.1 |
HIP 70608 |
15.79 |