88P/Howell
| Parameter |
Value |
| Designation |
88P/Howell |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2020-09-26T15:57:02.433600Z |
| Orbit solution date (soln_date, UTC) |
2025-09-09T14:40:12Z |
| Obs used |
3010 |
| NEO |
- |
| M1 |
12.100 |
| K1 |
9.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2019-03-13.0000000 |
| e |
0.56407157 |
| q (au) |
1.354032 |
| a (au) |
3.106088 |
| i (deg) |
4.383766 |
| Ω (om, deg) |
56.694879 |
| ω (w, deg) |
235.876298 |
| M (ma, deg) |
258.514429 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.044 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.044 |
| n |
6.000 |
| gf |
0.996 |
| gb |
-0.686 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
18:49:33.05 |
-24:05:37.7 |
HIP 92403 |
15.90 |
| 2026-02-03 12:00 |
18:51:25.03 |
-24:04:23.1 |
HIP 92403 |
26.16 |
| 2026-02-04 00:00 |
18:53:17.11 |
-24:03:03.4 |
HIP 92709 |
4.16 |
| 2026-02-04 12:00 |
18:55:09.28 |
-24:01:38.7 |
HIP 92709 |
23.58 |
| 2026-02-05 00:00 |
18:57:01.52 |
-24:00:09.0 |
HIP 93040 |
8.23 |
| 2026-02-05 12:00 |
18:58:53.85 |
-23:58:34.3 |
HIP 93040 |
24.71 |
| 2026-02-06 00:00 |
19:00:46.25 |
-23:56:54.6 |
HIP 93480 |
25.25 |
| 2026-02-06 12:00 |
19:02:38.73 |
-23:55:09.8 |
HIP 93480 |
14.60 |
| 2026-02-07 00:00 |
19:04:31.27 |
-23:53:20.0 |
HIP 93508 |
31.94 |
| 2026-02-07 12:00 |
19:06:23.87 |
-23:51:25.1 |
HIP 93902 |
11.63 |
| 2026-02-08 00:00 |
19:08:16.53 |
-23:49:25.2 |
HIP 93902 |
14.37 |
| 2026-02-08 12:00 |
19:10:09.24 |
-23:47:20.2 |
HIP 94238 |
26.41 |
| 2026-02-09 00:00 |
19:12:02.00 |
-23:45:10.2 |
HIP 94333 |
0.89 |
| 2026-02-09 12:00 |
19:13:54.81 |
-23:42:55.1 |
HIP 94333 |
25.36 |
| 2026-02-10 00:00 |
19:15:47.65 |
-23:40:35.0 |
HIP 94645 |
30.34 |
| 2026-02-10 12:00 |
19:17:40.53 |
-23:38:09.9 |
HIP 94951 |
22.75 |
| 2026-02-11 00:00 |
19:19:33.44 |
-23:35:39.7 |
HIP 94951 |
4.21 |
| 2026-02-11 12:00 |
19:21:26.37 |
-23:33:04.5 |
HIP 95124 |
6.51 |
| 2026-02-12 00:00 |
19:23:19.32 |
-23:30:24.2 |
HIP 95415 |
26.16 |
| 2026-02-12 12:00 |
19:25:12.30 |
-23:27:38.9 |
HIP 95415 |
19.29 |
| 2026-02-13 00:00 |
19:27:05.28 |
-23:24:48.6 |
HIP 95645 |
5.00 |
| 2026-02-13 12:00 |
19:28:58.27 |
-23:21:53.3 |
HIP 95645 |
22.93 |
| 2026-02-14 00:00 |
19:30:51.26 |
-23:18:53.0 |
HIP 96067 |
21.99 |
| 2026-02-14 12:00 |
19:32:44.25 |
-23:15:47.7 |
HIP 96067 |
21.51 |
| 2026-02-15 00:00 |
19:34:37.23 |
-23:12:37.4 |
HIP 96249 |
8.28 |
| 2026-02-15 12:00 |
19:36:30.20 |
-23:09:22.1 |
HIP 96431 |
3.41 |
| 2026-02-16 00:00 |
19:38:23.15 |
-23:06:01.9 |
HIP 96729 |
27.89 |
| 2026-02-16 12:00 |
19:40:16.09 |
-23:02:36.7 |
HIP 96785 |
19.01 |
| 2026-02-17 00:00 |
19:42:08.99 |
-22:59:06.7 |
HIP 96785 |
28.74 |
| 2026-02-17 12:00 |
19:44:01.87 |
-22:55:31.7 |
HIP 97138 |
8.23 |
| 2026-02-18 00:00 |
19:45:54.71 |
-22:51:51.8 |
HIP 97138 |
18.92 |
| 2026-02-18 12:00 |
19:47:47.52 |
-22:48:07.0 |
HIP 97381 |
4.21 |
| 2026-02-19 00:00 |
19:49:40.27 |
-22:44:17.4 |
HIP 97602 |
8.67 |
| 2026-02-19 12:00 |
19:51:32.98 |
-22:40:22.9 |
HIP 97718 |
17.34 |
| 2026-02-20 00:00 |
19:53:25.64 |
-22:36:23.6 |
HIP 97981 |
18.31 |
| 2026-02-20 12:00 |
19:55:18.24 |
-22:32:19.5 |
HIP 97981 |
8.99 |
| 2026-02-21 00:00 |
19:57:10.78 |
-22:28:10.6 |
HIP 98134 |
16.37 |
| 2026-02-21 12:00 |
19:59:03.25 |
-22:23:57.0 |
HIP 98318 |
11.15 |
| 2026-02-22 00:00 |
20:00:55.65 |
-22:19:38.6 |
HIP 98599 |
16.31 |
| 2026-02-22 12:00 |
20:02:47.98 |
-22:15:15.6 |
HIP 98599 |
18.31 |
| 2026-02-23 00:00 |
20:04:40.23 |
-22:10:47.8 |
HIP 98851 |
3.27 |
| 2026-02-23 12:00 |
20:06:32.39 |
-22:06:15.4 |
HIP 99046 |
25.66 |
| 2026-02-24 00:00 |
20:08:24.47 |
-22:01:38.3 |
HIP 99337 |
19.98 |