C/2015 VL62 (Lemmon-Yeung-PANSTARRS)
| Parameter |
Value |
| Designation |
C/2015 VL62 (Lemmon-Yeung-PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-08-28T14:12:57.562560Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:17Z |
| Obs used |
2115 |
| NEO |
- |
| M1 |
11.400 |
| K1 |
5.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-03-17.0000000 |
| e |
1.00203088 |
| q (au) |
2.720271 |
| a (au) |
-1339.452215 |
| i (deg) |
165.614083 |
| Ω (om, deg) |
94.546143 |
| ω (w, deg) |
128.359439 |
| M (ma, deg) |
-0.003309 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.545 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.545 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.825 |
| k |
0.999 |
| 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) |
| 2026-02-03 00:00 |
12:17:02.76 |
-17:41:49.7 |
HIP 59803 |
20.00 |
| 2026-02-03 12:00 |
12:16:58.53 |
-17:41:43.0 |
HIP 59803 |
19.06 |
| 2026-02-04 00:00 |
12:16:54.25 |
-17:41:36.0 |
HIP 59803 |
18.12 |
| 2026-02-04 12:00 |
12:16:49.94 |
-17:41:28.6 |
HIP 59803 |
17.17 |
| 2026-02-05 00:00 |
12:16:45.58 |
-17:41:20.8 |
HIP 59803 |
16.22 |
| 2026-02-05 12:00 |
12:16:41.19 |
-17:41:12.7 |
HIP 59803 |
15.28 |
| 2026-02-06 00:00 |
12:16:36.76 |
-17:41:04.1 |
HIP 59803 |
14.34 |
| 2026-02-06 12:00 |
12:16:32.29 |
-17:40:55.3 |
HIP 59803 |
13.40 |
| 2026-02-07 00:00 |
12:16:27.78 |
-17:40:46.0 |
HIP 59803 |
12.48 |
| 2026-02-07 12:00 |
12:16:23.23 |
-17:40:36.4 |
HIP 59803 |
11.58 |
| 2026-02-08 00:00 |
12:16:18.65 |
-17:40:26.4 |
HIP 59803 |
10.70 |
| 2026-02-08 12:00 |
12:16:14.03 |
-17:40:16.0 |
HIP 59803 |
9.86 |
| 2026-02-09 00:00 |
12:16:09.37 |
-17:40:05.3 |
HIP 59803 |
9.06 |
| 2026-02-09 12:00 |
12:16:04.68 |
-17:39:54.2 |
HIP 59803 |
8.33 |
| 2026-02-10 00:00 |
12:15:59.95 |
-17:39:42.8 |
HIP 59803 |
7.70 |
| 2026-02-10 12:00 |
12:15:55.18 |
-17:39:30.9 |
HIP 59803 |
7.18 |
| 2026-02-11 00:00 |
12:15:50.38 |
-17:39:18.7 |
HIP 59803 |
6.81 |
| 2026-02-11 12:00 |
12:15:45.54 |
-17:39:06.2 |
HIP 59803 |
6.62 |
| 2026-02-12 00:00 |
12:15:40.67 |
-17:38:53.3 |
HIP 59803 |
6.63 |
| 2026-02-12 12:00 |
12:15:35.76 |
-17:38:40.0 |
HIP 59803 |
6.85 |
| 2026-02-13 00:00 |
12:15:30.82 |
-17:38:26.3 |
HIP 59803 |
7.26 |
| 2026-02-13 12:00 |
12:15:25.85 |
-17:38:12.3 |
HIP 59803 |
7.83 |
| 2026-02-14 00:00 |
12:15:20.84 |
-17:37:57.9 |
HIP 59803 |
8.54 |
| 2026-02-14 12:00 |
12:15:15.80 |
-17:37:43.1 |
HIP 59803 |
9.36 |
| 2026-02-15 00:00 |
12:15:10.72 |
-17:37:28.0 |
HIP 59803 |
10.27 |
| 2026-02-15 12:00 |
12:15:05.62 |
-17:37:12.5 |
HIP 59803 |
11.24 |
| 2026-02-16 00:00 |
12:15:00.48 |
-17:36:56.7 |
HIP 59803 |
12.26 |
| 2026-02-16 12:00 |
12:14:55.31 |
-17:36:40.4 |
HIP 59803 |
13.33 |
| 2026-02-17 00:00 |
12:14:50.11 |
-17:36:23.9 |
HIP 59803 |
14.44 |
| 2026-02-17 12:00 |
12:14:44.88 |
-17:36:06.9 |
HIP 59803 |
15.58 |
| 2026-02-18 00:00 |
12:14:39.62 |
-17:35:49.6 |
HIP 59803 |
16.74 |
| 2026-02-18 12:00 |
12:14:34.33 |
-17:35:32.0 |
HIP 59803 |
17.93 |
| 2026-02-19 00:00 |
12:14:29.01 |
-17:35:14.0 |
HIP 59803 |
19.13 |
| 2026-02-19 12:00 |
12:14:23.66 |
-17:34:55.6 |
HIP 59803 |
20.36 |
| 2026-02-20 00:00 |
12:14:18.28 |
-17:34:36.9 |
HIP 59803 |
21.60 |
| 2026-02-20 12:00 |
12:14:12.87 |
-17:34:17.8 |
HIP 59803 |
22.86 |
| 2026-02-21 00:00 |
12:14:07.44 |
-17:33:58.4 |
HIP 59803 |
24.13 |
| 2026-02-21 12:00 |
12:14:01.98 |
-17:33:38.6 |
HIP 59803 |
25.41 |
| 2026-02-22 00:00 |
12:13:56.49 |
-17:33:18.5 |
HIP 59803 |
26.70 |
| 2026-02-22 12:00 |
12:13:50.97 |
-17:32:58.1 |
HIP 59573 |
27.91 |
| 2026-02-23 00:00 |
12:13:45.43 |
-17:32:37.2 |
HIP 59573 |
27.02 |
| 2026-02-23 12:00 |
12:13:39.87 |
-17:32:16.1 |
HIP 59573 |
26.16 |
| 2026-02-24 00:00 |
12:13:34.28 |
-17:31:54.6 |
HIP 59573 |
25.34 |