P/2015 B4 (Lemmon-PANSTARRS)
| Parameter |
Value |
| Designation |
P/2015 B4 (Lemmon-PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2015-02-17T15:37:40.232640Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:05Z |
| Obs used |
77 |
| NEO |
- |
| M1 |
15.200 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-11-20.0000000 |
| e |
0.56891192 |
| q (au) |
3.755337 |
| a (au) |
8.711300 |
| i (deg) |
1.742618 |
| Ω (om, deg) |
266.651081 |
| ω (w, deg) |
227.778528 |
| M (ma, deg) |
10.555113 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.526 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.526 |
| n |
2.000 |
| gf |
0.947 |
| gb |
-0.830 |
| k |
0.993 |
| δ90 |
1.000 |
| 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) |
| 2026-02-03 00:00 |
20:35:24.14 |
-17:33:45.8 |
HIP 101596 |
13.52 |
| 2026-02-03 12:00 |
20:35:34.23 |
-17:33:07.7 |
HIP 101596 |
14.35 |
| 2026-02-04 00:00 |
20:35:44.31 |
-17:32:29.7 |
HIP 101596 |
15.54 |
| 2026-02-04 12:00 |
20:35:54.38 |
-17:31:51.6 |
HIP 101596 |
17.01 |
| 2026-02-05 00:00 |
20:36:04.44 |
-17:31:13.5 |
HIP 101596 |
18.69 |
| 2026-02-05 12:00 |
20:36:14.49 |
-17:30:35.3 |
HIP 101596 |
20.53 |
| 2026-02-06 00:00 |
20:36:24.53 |
-17:29:57.2 |
HIP 101596 |
22.50 |
| 2026-02-06 12:00 |
20:36:34.56 |
-17:29:19.0 |
HIP 101596 |
24.55 |
| 2026-02-07 00:00 |
20:36:44.57 |
-17:28:40.9 |
HIP 101799 |
26.29 |
| 2026-02-07 12:00 |
20:36:54.57 |
-17:28:02.7 |
HIP 101799 |
24.43 |
| 2026-02-08 00:00 |
20:37:04.55 |
-17:27:24.6 |
HIP 101799 |
22.69 |
| 2026-02-08 12:00 |
20:37:14.53 |
-17:26:46.4 |
HIP 101799 |
21.09 |
| 2026-02-09 00:00 |
20:37:24.48 |
-17:26:08.2 |
HIP 101799 |
19.68 |
| 2026-02-09 12:00 |
20:37:34.42 |
-17:25:30.0 |
HIP 101799 |
18.48 |
| 2026-02-10 00:00 |
20:37:44.35 |
-17:24:51.9 |
HIP 101799 |
17.55 |
| 2026-02-10 12:00 |
20:37:54.26 |
-17:24:13.7 |
HIP 101799 |
16.93 |
| 2026-02-11 00:00 |
20:38:04.15 |
-17:23:35.5 |
HIP 101799 |
16.65 |
| 2026-02-11 12:00 |
20:38:14.02 |
-17:22:57.4 |
HIP 101799 |
16.72 |
| 2026-02-12 00:00 |
20:38:23.88 |
-17:22:19.3 |
HIP 101799 |
17.15 |
| 2026-02-12 12:00 |
20:38:33.71 |
-17:21:41.1 |
HIP 101799 |
17.89 |
| 2026-02-13 00:00 |
20:38:43.53 |
-17:21:03.0 |
HIP 101879 |
17.14 |
| 2026-02-13 12:00 |
20:38:53.33 |
-17:20:24.9 |
HIP 101879 |
16.70 |
| 2026-02-14 00:00 |
20:39:03.11 |
-17:19:46.9 |
HIP 101879 |
16.61 |
| 2026-02-14 12:00 |
20:39:12.87 |
-17:19:08.8 |
HIP 101879 |
16.87 |
| 2026-02-15 00:00 |
20:39:22.61 |
-17:18:30.8 |
HIP 101879 |
17.46 |
| 2026-02-15 12:00 |
20:39:32.33 |
-17:17:52.8 |
HIP 101879 |
18.35 |
| 2026-02-16 00:00 |
20:39:42.02 |
-17:17:14.8 |
HIP 101879 |
19.49 |
| 2026-02-16 12:00 |
20:39:51.69 |
-17:16:36.9 |
HIP 101879 |
20.85 |
| 2026-02-17 00:00 |
20:40:01.34 |
-17:15:59.0 |
HIP 102085 |
19.75 |
| 2026-02-17 12:00 |
20:40:10.96 |
-17:15:21.1 |
HIP 102085 |
17.86 |
| 2026-02-18 00:00 |
20:40:20.56 |
-17:14:43.3 |
HIP 102085 |
16.10 |
| 2026-02-18 12:00 |
20:40:30.14 |
-17:14:05.5 |
HIP 102085 |
14.53 |
| 2026-02-19 00:00 |
20:40:39.69 |
-17:13:27.7 |
HIP 102085 |
13.20 |
| 2026-02-19 12:00 |
20:40:49.22 |
-17:12:50.0 |
HIP 102085 |
12.19 |
| 2026-02-20 00:00 |
20:40:58.71 |
-17:12:12.4 |
HIP 102085 |
11.58 |
| 2026-02-20 12:00 |
20:41:08.19 |
-17:11:34.8 |
HIP 102085 |
11.43 |
| 2026-02-21 00:00 |
20:41:17.63 |
-17:10:57.2 |
HIP 102085 |
11.76 |
| 2026-02-21 12:00 |
20:41:27.05 |
-17:10:19.7 |
HIP 102178 |
12.33 |
| 2026-02-22 00:00 |
20:41:36.44 |
-17:09:42.3 |
HIP 102178 |
10.06 |
| 2026-02-22 12:00 |
20:41:45.80 |
-17:09:04.9 |
HIP 102178 |
7.83 |
| 2026-02-23 00:00 |
20:41:55.13 |
-17:08:27.6 |
HIP 102178 |
5.68 |
| 2026-02-23 12:00 |
20:42:04.43 |
-17:07:50.3 |
HIP 102178 |
3.73 |
| 2026-02-24 00:00 |
20:42:13.70 |
-17:07:13.1 |
HIP 102178 |
2.50 |