| Parameter |
Value |
| Designation |
77P/Longmore |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2016-05-14T10:40:08.040000Z |
| Orbit solution date (soln_date, UTC) |
2025-10-29T22:11:34Z |
| Obs used |
2629 |
| NEO |
- |
| M1 |
9.300 |
| K1 |
14.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2014-02-05.0000000 |
| e |
0.35416745 |
| q (au) |
2.333302 |
| a (au) |
3.612860 |
| i (deg) |
24.340171 |
| Ω (om, deg) |
14.886903 |
| ω (w, deg) |
196.946173 |
| M (ma, deg) |
240.954013 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.016 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.016 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.866 |
| 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) |
| 2026-07-29 00:00 |
02:18:45.49 |
+19:40:54.3 |
HIP 10810 |
5.48 |
| 2026-07-29 12:00 |
02:18:52.67 |
+19:43:00.6 |
HIP 10810 |
4.16 |
| 2026-07-30 00:00 |
02:18:59.68 |
+19:45:06.3 |
HIP 10810 |
4.38 |
| 2026-07-30 12:00 |
02:19:06.51 |
+19:47:11.4 |
HIP 10810 |
5.93 |
| 2026-07-31 00:00 |
02:19:13.16 |
+19:49:16.0 |
HIP 10810 |
8.05 |
| 2026-07-31 12:00 |
02:19:19.63 |
+19:51:19.9 |
HIP 10810 |
10.37 |
| 2026-08-01 00:00 |
02:19:25.93 |
+19:53:23.2 |
HIP 10810 |
12.76 |
| 2026-08-01 12:00 |
02:19:32.04 |
+19:55:25.9 |
HIP 10810 |
15.18 |
| 2026-08-02 00:00 |
02:19:37.97 |
+19:57:28.0 |
HIP 10810 |
17.59 |
| 2026-08-02 12:00 |
02:19:43.71 |
+19:59:29.5 |
HIP 10810 |
19.98 |
| 2026-08-03 00:00 |
02:19:49.27 |
+20:01:30.3 |
HIP 10810 |
22.36 |
| 2026-08-03 12:00 |
02:19:54.65 |
+20:03:30.6 |
HIP 10810 |
24.71 |
| 2026-08-04 00:00 |
02:19:59.83 |
+20:05:30.2 |
HIP 10810 |
27.04 |
| 2026-08-04 12:00 |
02:20:04.83 |
+20:07:29.1 |
HIP 10810 |
29.34 |
| 2026-08-05 00:00 |
02:20:09.64 |
+20:09:27.4 |
HIP 10810 |
31.60 |
| 2026-08-05 12:00 |
02:20:14.27 |
+20:11:25.1 |
HIP 11032 |
31.48 |
| 2026-08-06 00:00 |
02:20:18.70 |
+20:13:22.1 |
HIP 11032 |
29.53 |
| 2026-08-06 12:00 |
02:20:22.93 |
+20:15:18.4 |
HIP 11032 |
27.67 |
| 2026-08-07 00:00 |
02:20:26.98 |
+20:17:14.1 |
HIP 11032 |
25.91 |
| 2026-08-07 12:00 |
02:20:30.83 |
+20:19:09.1 |
HIP 11032 |
24.25 |
| 2026-08-08 00:00 |
02:20:34.48 |
+20:21:03.4 |
HIP 11032 |
22.72 |
| 2026-08-08 12:00 |
02:20:37.94 |
+20:22:57.0 |
HIP 11032 |
21.33 |
| 2026-08-09 00:00 |
02:20:41.20 |
+20:24:50.0 |
HIP 11032 |
20.11 |
| 2026-08-09 12:00 |
02:20:44.26 |
+20:26:42.2 |
HIP 11032 |
19.07 |
| 2026-08-10 00:00 |
02:20:47.12 |
+20:28:33.8 |
HIP 11032 |
18.24 |
| 2026-08-10 12:00 |
02:20:49.79 |
+20:30:24.6 |
HIP 11032 |
17.64 |
| 2026-08-11 00:00 |
02:20:52.25 |
+20:32:14.7 |
HIP 11032 |
17.29 |
| 2026-08-11 12:00 |
02:20:54.50 |
+20:34:04.1 |
HIP 11032 |
17.18 |
| 2026-08-12 00:00 |
02:20:56.56 |
+20:35:52.8 |
HIP 11032 |
17.33 |
| 2026-08-12 12:00 |
02:20:58.41 |
+20:37:40.8 |
HIP 11032 |
17.71 |
| 2026-08-13 00:00 |
02:21:00.05 |
+20:39:28.0 |
HIP 11032 |
18.31 |
| 2026-08-13 12:00 |
02:21:01.49 |
+20:41:14.5 |
HIP 11032 |
19.09 |
| 2026-08-14 00:00 |
02:21:02.72 |
+20:43:00.2 |
HIP 11032 |
20.04 |
| 2026-08-14 12:00 |
02:21:03.74 |
+20:44:45.2 |
HIP 11032 |
21.11 |
| 2026-08-15 00:00 |
02:21:04.56 |
+20:46:29.5 |
HIP 11032 |
22.30 |
| 2026-08-15 12:00 |
02:21:05.17 |
+20:48:13.0 |
HIP 11032 |
23.57 |
| 2026-08-16 00:00 |
02:21:05.56 |
+20:49:55.7 |
HIP 11032 |
24.92 |
| 2026-08-16 12:00 |
02:21:05.75 |
+20:51:37.6 |
HIP 11032 |
26.32 |
| 2026-08-17 00:00 |
02:21:05.73 |
+20:53:18.8 |
HIP 11032 |
27.77 |
| 2026-08-17 12:00 |
02:21:05.50 |
+20:54:59.2 |
HIP 11032 |
29.26 |
| 2026-08-18 00:00 |
02:21:05.05 |
+20:56:38.8 |
HIP 11076 |
30.33 |
| 2026-08-18 12:00 |
02:21:04.40 |
+20:58:17.6 |
HIP 11076 |
29.26 |
| 2026-08-19 00:00 |
02:21:03.53 |
+20:59:55.6 |
HIP 11076 |
28.29 |