| Parameter |
Value |
| Designation |
200P/Larsen |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2008-08-25T00:09:36.175680Z |
| Orbit solution date (soln_date, UTC) |
2022-02-03T20:43:19Z |
| Obs used |
610 |
| NEO |
- |
| M1 |
7.000 |
| K1 |
17.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2008-01-06.0000000 |
| e |
0.33323678 |
| q (au) |
3.272199 |
| a (au) |
4.907588 |
| i (deg) |
12.121060 |
| Ω (om, deg) |
234.819218 |
| ω (w, deg) |
133.693288 |
| M (ma, deg) |
338.966942 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.603 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.603 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.501 |
| 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 |
13:39:42.91 |
-16:13:19.1 |
HIP 66663 |
13.98 |
| 2026-05-12 12:00 |
13:39:30.94 |
-16:11:38.3 |
HIP 66663 |
16.53 |
| 2026-05-13 00:00 |
13:39:19.05 |
-16:09:57.7 |
HIP 66663 |
19.31 |
| 2026-05-13 12:00 |
13:39:07.26 |
-16:08:17.3 |
HIP 66663 |
22.22 |
| 2026-05-14 00:00 |
13:38:55.56 |
-16:06:37.1 |
HIP 66663 |
25.20 |
| 2026-05-14 12:00 |
13:38:43.95 |
-16:04:57.2 |
HIP 66663 |
28.23 |
| 2026-05-15 00:00 |
13:38:32.44 |
-16:03:17.5 |
HIP 66636 |
30.22 |
| 2026-05-15 12:00 |
13:38:21.02 |
-16:01:38.1 |
HIP 66636 |
30.29 |
| 2026-05-16 00:00 |
13:38:09.70 |
-15:59:59.0 |
HIP 66636 |
30.69 |
| 2026-05-16 12:00 |
13:37:58.48 |
-15:58:20.2 |
HIP 66636 |
31.40 |
| 2026-05-17 00:00 |
13:37:47.36 |
-15:56:41.7 |
HIP 66423 |
31.94 |
| 2026-05-17 12:00 |
13:37:36.34 |
-15:55:03.5 |
HIP 66423 |
32.75 |
| 2026-05-18 00:00 |
13:37:25.43 |
-15:53:25.6 |
HIP 66423 |
33.82 |
| 2026-05-18 12:00 |
13:37:14.63 |
-15:51:48.1 |
HIP 66504 |
35.12 |
| 2026-05-19 00:00 |
13:37:03.93 |
-15:50:11.0 |
HIP 66504 |
34.47 |
| 2026-05-19 12:00 |
13:36:53.34 |
-15:48:34.2 |
HIP 66504 |
34.07 |
| 2026-05-20 00:00 |
13:36:42.86 |
-15:46:57.8 |
HIP 66504 |
33.93 |
| 2026-05-20 12:00 |
13:36:32.49 |
-15:45:21.8 |
HIP 66504 |
34.04 |
| 2026-05-21 00:00 |
13:36:22.24 |
-15:43:46.3 |
HIP 66504 |
34.40 |
| 2026-05-21 12:00 |
13:36:12.10 |
-15:42:11.1 |
HIP 66504 |
34.98 |
| 2026-05-22 00:00 |
13:36:02.07 |
-15:40:36.4 |
HIP 66504 |
35.77 |
| 2026-05-22 12:00 |
13:35:52.16 |
-15:39:02.1 |
HIP 66504 |
36.76 |
| 2026-05-23 00:00 |
13:35:42.37 |
-15:37:28.3 |
HIP 66504 |
37.92 |
| 2026-05-23 12:00 |
13:35:32.70 |
-15:35:54.9 |
HIP 66338 |
36.97 |
| 2026-05-24 00:00 |
13:35:23.15 |
-15:34:22.0 |
HIP 66338 |
35.66 |
| 2026-05-24 12:00 |
13:35:13.72 |
-15:32:49.6 |
HIP 66338 |
34.53 |
| 2026-05-25 00:00 |
13:35:04.41 |
-15:31:17.7 |
HIP 66091 |
33.37 |
| 2026-05-25 12:00 |
13:34:55.23 |
-15:29:46.4 |
HIP 66091 |
30.83 |
| 2026-05-26 00:00 |
13:34:46.17 |
-15:28:15.5 |
HIP 66091 |
28.34 |
| 2026-05-26 12:00 |
13:34:37.23 |
-15:26:45.1 |
HIP 66091 |
25.92 |
| 2026-05-27 00:00 |
13:34:28.42 |
-15:25:15.3 |
HIP 66091 |
23.57 |
| 2026-05-27 12:00 |
13:34:19.74 |
-15:23:46.1 |
HIP 66091 |
21.32 |
| 2026-05-28 00:00 |
13:34:11.19 |
-15:22:17.3 |
HIP 66091 |
19.17 |
| 2026-05-28 12:00 |
13:34:02.76 |
-15:20:49.2 |
HIP 66091 |
17.16 |
| 2026-05-29 00:00 |
13:33:54.47 |
-15:19:21.6 |
HIP 66091 |
15.33 |
| 2026-05-29 12:00 |
13:33:46.30 |
-15:17:54.6 |
HIP 66091 |
13.72 |
| 2026-05-30 00:00 |
13:33:38.27 |
-15:16:28.2 |
HIP 66091 |
12.42 |
| 2026-05-30 12:00 |
13:33:30.36 |
-15:15:02.4 |
HIP 66091 |
11.51 |
| 2026-05-31 00:00 |
13:33:22.60 |
-15:13:37.2 |
HIP 66091 |
11.05 |
| 2026-05-31 12:00 |
13:33:14.96 |
-15:12:12.6 |
HIP 66091 |
11.09 |
| 2026-06-01 00:00 |
13:33:07.46 |
-15:10:48.7 |
HIP 66091 |
11.61 |
| 2026-06-01 12:00 |
13:33:00.09 |
-15:09:25.4 |
HIP 66091 |
12.52 |
| 2026-06-02 00:00 |
13:32:52.86 |
-15:08:02.7 |
HIP 66091 |
13.74 |