| 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 |
9.985 |
| 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) |
| 2026-07-29 00:00 |
14:01:06.36 |
-16:26:29.0 |
HIP 68451 |
7.92 |
| 2026-07-29 12:00 |
14:01:09.17 |
-16:26:31.0 |
HIP 68451 |
8.29 |
| 2026-07-30 00:00 |
14:01:12.09 |
-16:26:33.6 |
HIP 68451 |
8.71 |
| 2026-07-30 12:00 |
14:01:15.10 |
-16:26:36.7 |
HIP 68451 |
9.19 |
| 2026-07-31 00:00 |
14:01:18.22 |
-16:26:40.4 |
HIP 68451 |
9.73 |
| 2026-07-31 12:00 |
14:01:21.44 |
-16:26:44.6 |
HIP 68451 |
10.31 |
| 2026-08-01 00:00 |
14:01:24.77 |
-16:26:49.4 |
HIP 68451 |
10.95 |
| 2026-08-01 12:00 |
14:01:28.19 |
-16:26:54.7 |
HIP 68451 |
11.63 |
| 2026-08-02 00:00 |
14:01:31.71 |
-16:27:00.7 |
HIP 68451 |
12.35 |
| 2026-08-02 12:00 |
14:01:35.33 |
-16:27:07.1 |
HIP 68451 |
13.11 |
| 2026-08-03 00:00 |
14:01:39.06 |
-16:27:14.1 |
HIP 68451 |
13.91 |
| 2026-08-03 12:00 |
14:01:42.88 |
-16:27:21.7 |
HIP 68451 |
14.75 |
| 2026-08-04 00:00 |
14:01:46.80 |
-16:27:29.8 |
HIP 68451 |
15.62 |
| 2026-08-04 12:00 |
14:01:50.82 |
-16:27:38.5 |
HIP 68451 |
16.53 |
| 2026-08-05 00:00 |
14:01:54.94 |
-16:27:47.8 |
HIP 68451 |
17.46 |
| 2026-08-05 12:00 |
14:01:59.15 |
-16:27:57.5 |
HIP 68451 |
18.43 |
| 2026-08-06 00:00 |
14:02:03.47 |
-16:28:07.9 |
HIP 68451 |
19.43 |
| 2026-08-06 12:00 |
14:02:07.88 |
-16:28:18.8 |
HIP 68451 |
20.47 |
| 2026-08-07 00:00 |
14:02:12.39 |
-16:28:30.2 |
HIP 68451 |
21.53 |
| 2026-08-07 12:00 |
14:02:17.00 |
-16:28:42.2 |
HIP 68451 |
22.61 |
| 2026-08-08 00:00 |
14:02:21.70 |
-16:28:54.7 |
HIP 68451 |
23.73 |
| 2026-08-08 12:00 |
14:02:26.50 |
-16:29:07.7 |
HIP 68451 |
24.87 |
| 2026-08-09 00:00 |
14:02:31.39 |
-16:29:21.3 |
HIP 68451 |
26.04 |
| 2026-08-09 12:00 |
14:02:36.39 |
-16:29:35.5 |
HIP 68451 |
27.24 |
| 2026-08-10 00:00 |
14:02:41.47 |
-16:29:50.1 |
HIP 68451 |
28.47 |
| 2026-08-10 12:00 |
14:02:46.65 |
-16:30:05.4 |
HIP 68451 |
29.72 |
| 2026-08-11 00:00 |
14:02:51.93 |
-16:30:21.1 |
HIP 68451 |
30.99 |
| 2026-08-11 12:00 |
14:02:57.30 |
-16:30:37.4 |
HIP 68451 |
32.30 |
| 2026-08-12 00:00 |
14:03:02.77 |
-16:30:54.2 |
HIP 68808 |
33.26 |
| 2026-08-12 12:00 |
14:03:08.33 |
-16:31:11.5 |
HIP 68808 |
32.09 |
| 2026-08-13 00:00 |
14:03:13.98 |
-16:31:29.4 |
HIP 68808 |
30.93 |
| 2026-08-13 12:00 |
14:03:19.72 |
-16:31:47.8 |
HIP 68808 |
29.77 |
| 2026-08-14 00:00 |
14:03:25.56 |
-16:32:06.7 |
HIP 68808 |
28.62 |
| 2026-08-14 12:00 |
14:03:31.49 |
-16:32:26.2 |
HIP 68808 |
27.48 |
| 2026-08-15 00:00 |
14:03:37.50 |
-16:32:46.1 |
HIP 68808 |
26.35 |
| 2026-08-15 12:00 |
14:03:43.61 |
-16:33:06.6 |
HIP 68808 |
25.25 |
| 2026-08-16 00:00 |
14:03:49.81 |
-16:33:27.6 |
HIP 68808 |
24.18 |
| 2026-08-16 12:00 |
14:03:56.10 |
-16:33:49.1 |
HIP 68808 |
23.14 |
| 2026-08-17 00:00 |
14:04:02.48 |
-16:34:11.1 |
HIP 68808 |
22.15 |
| 2026-08-17 12:00 |
14:04:08.95 |
-16:34:33.6 |
HIP 68808 |
21.23 |
| 2026-08-18 00:00 |
14:04:15.51 |
-16:34:56.6 |
HIP 68808 |
20.38 |
| 2026-08-18 12:00 |
14:04:22.15 |
-16:35:20.1 |
HIP 68808 |
19.62 |
| 2026-08-19 00:00 |
14:04:28.88 |
-16:35:44.1 |
HIP 68808 |
18.96 |