| Parameter |
Value |
| Designation |
36P/Whipple |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2012-01-01T11:32:39.073920Z |
| Orbit solution date (soln_date, UTC) |
2023-08-28T08:56:03Z |
| Obs used |
943 |
| NEO |
- |
| M1 |
10.500 |
| K1 |
13.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2008-08-12.0000000 |
| e |
0.25822503 |
| q (au) |
3.089226 |
| a (au) |
4.164640 |
| i (deg) |
9.935343 |
| Ω (om, deg) |
182.391226 |
| ω (w, deg) |
201.955974 |
| M (ma, deg) |
216.491915 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.524 + 5.641\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.524 |
| n |
5.641 |
| gf |
1.000 |
| gb |
-0.683 |
| k |
0.800 |
| 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) |
| 2026-03-26 00:00 |
17:11:41.55 |
-13:09:05.1 |
HIP 84220 |
28.90 |
| 2026-03-26 12:00 |
17:11:45.87 |
-13:07:56.8 |
HIP 84220 |
27.35 |
| 2026-03-27 00:00 |
17:11:49.99 |
-13:06:48.3 |
HIP 84220 |
25.83 |
| 2026-03-27 12:00 |
17:11:53.89 |
-13:05:39.3 |
HIP 84220 |
24.34 |
| 2026-03-28 00:00 |
17:11:57.59 |
-13:04:30.0 |
HIP 84220 |
22.88 |
| 2026-03-28 12:00 |
17:12:01.07 |
-13:03:20.4 |
HIP 84220 |
21.44 |
| 2026-03-29 00:00 |
17:12:04.33 |
-13:02:10.4 |
HIP 84220 |
20.03 |
| 2026-03-29 12:00 |
17:12:07.39 |
-13:01:00.1 |
HIP 84220 |
18.65 |
| 2026-03-30 00:00 |
17:12:10.23 |
-12:59:49.5 |
HIP 84220 |
17.30 |
| 2026-03-30 12:00 |
17:12:12.86 |
-12:58:38.6 |
HIP 84220 |
15.98 |
| 2026-03-31 00:00 |
17:12:15.27 |
-12:57:27.3 |
HIP 84220 |
14.70 |
| 2026-03-31 12:00 |
17:12:17.47 |
-12:56:15.7 |
HIP 84220 |
13.46 |
| 2026-04-01 00:00 |
17:12:19.45 |
-12:55:03.8 |
HIP 84220 |
12.26 |
| 2026-04-01 12:00 |
17:12:21.22 |
-12:53:51.6 |
HIP 84220 |
11.12 |
| 2026-04-02 00:00 |
17:12:22.77 |
-12:52:39.1 |
HIP 84220 |
10.06 |
| 2026-04-02 12:00 |
17:12:24.11 |
-12:51:26.3 |
HIP 84220 |
9.08 |
| 2026-04-03 00:00 |
17:12:25.22 |
-12:50:13.2 |
HIP 84220 |
8.23 |
| 2026-04-03 12:00 |
17:12:26.13 |
-12:48:59.9 |
HIP 84220 |
7.54 |
| 2026-04-04 00:00 |
17:12:26.81 |
-12:47:46.2 |
HIP 84220 |
7.05 |
| 2026-04-04 12:00 |
17:12:27.28 |
-12:46:32.3 |
HIP 84220 |
6.81 |
| 2026-04-05 00:00 |
17:12:27.53 |
-12:45:18.1 |
HIP 84220 |
6.84 |
| 2026-04-05 12:00 |
17:12:27.56 |
-12:44:03.7 |
HIP 84220 |
7.14 |
| 2026-04-06 00:00 |
17:12:27.37 |
-12:42:49.0 |
HIP 84220 |
7.69 |
| 2026-04-06 12:00 |
17:12:26.97 |
-12:41:34.1 |
HIP 84220 |
8.43 |
| 2026-04-07 00:00 |
17:12:26.34 |
-12:40:18.9 |
HIP 84220 |
9.33 |
| 2026-04-07 12:00 |
17:12:25.50 |
-12:39:03.5 |
HIP 84220 |
10.34 |
| 2026-04-08 00:00 |
17:12:24.43 |
-12:37:47.8 |
HIP 84220 |
11.44 |
| 2026-04-08 12:00 |
17:12:23.15 |
-12:36:31.9 |
HIP 84220 |
12.61 |
| 2026-04-09 00:00 |
17:12:21.65 |
-12:35:15.8 |
HIP 84220 |
13.85 |
| 2026-04-09 12:00 |
17:12:19.92 |
-12:33:59.5 |
HIP 84220 |
15.13 |
| 2026-04-10 00:00 |
17:12:17.98 |
-12:32:43.0 |
HIP 84220 |
16.45 |
| 2026-04-10 12:00 |
17:12:15.82 |
-12:31:26.3 |
HIP 84220 |
17.81 |
| 2026-04-11 00:00 |
17:12:13.43 |
-12:30:09.5 |
HIP 84220 |
19.20 |
| 2026-04-11 12:00 |
17:12:10.83 |
-12:28:52.4 |
HIP 84220 |
20.63 |
| 2026-04-12 00:00 |
17:12:08.01 |
-12:27:35.1 |
HIP 84220 |
22.09 |
| 2026-04-12 12:00 |
17:12:04.96 |
-12:26:17.7 |
HIP 84220 |
23.57 |
| 2026-04-13 00:00 |
17:12:01.70 |
-12:25:00.2 |
HIP 84220 |
25.09 |
| 2026-04-13 12:00 |
17:11:58.22 |
-12:23:42.4 |
HIP 84034 |
25.88 |
| 2026-04-14 00:00 |
17:11:54.52 |
-12:22:24.5 |
HIP 84034 |
26.21 |
| 2026-04-14 12:00 |
17:11:50.59 |
-12:21:06.5 |
HIP 84034 |
26.60 |
| 2026-04-15 00:00 |
17:11:46.45 |
-12:19:48.4 |
HIP 84034 |
27.05 |
| 2026-04-15 12:00 |
17:11:42.09 |
-12:18:30.1 |
HIP 84034 |
27.57 |
| 2026-04-16 00:00 |
17:11:37.51 |
-12:17:11.7 |
HIP 84034 |
28.15 |