C/1987 T1 (Levy)
| Parameter |
Value |
| Designation |
C/1987 T1 (Levy) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1987-09-09T04:04:28.231680Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:33Z |
| Obs used |
18 |
| NEO |
- |
| M1 |
9.200 |
| K1 |
31.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1987-10-24.0000000 |
| e |
0.99999043 |
| q (au) |
0.515261 |
| a (au) |
53860.674252 |
| i (deg) |
62.532659 |
| Ω (om, deg) |
143.730188 |
| ω (w, deg) |
13.191234 |
| M (ma, deg) |
0.000004 |
Magnitude
Scatter + Global Linear
$$
M_a = (7.708 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.708 |
| n |
6.000 |
| gf |
0.994 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
9.999 |
| 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 |
21:52:02.28 |
-15:37:05.6 |
HIP 108078 |
28.77 |
| 2026-02-03 12:00 |
21:52:04.09 |
-15:36:56.5 |
HIP 108078 |
28.31 |
| 2026-02-04 00:00 |
21:52:05.89 |
-15:36:47.3 |
HIP 108078 |
27.85 |
| 2026-02-04 12:00 |
21:52:07.70 |
-15:36:38.1 |
HIP 108078 |
27.39 |
| 2026-02-05 00:00 |
21:52:09.51 |
-15:36:28.9 |
HIP 108078 |
26.93 |
| 2026-02-05 12:00 |
21:52:11.33 |
-15:36:19.7 |
HIP 108078 |
26.47 |
| 2026-02-06 00:00 |
21:52:13.14 |
-15:36:10.5 |
HIP 108078 |
26.01 |
| 2026-02-06 12:00 |
21:52:14.96 |
-15:36:01.3 |
HIP 108078 |
25.55 |
| 2026-02-07 00:00 |
21:52:16.78 |
-15:35:52.1 |
HIP 108078 |
25.08 |
| 2026-02-07 12:00 |
21:52:18.60 |
-15:35:42.9 |
HIP 108078 |
24.62 |
| 2026-02-08 00:00 |
21:52:20.43 |
-15:35:33.7 |
HIP 108078 |
24.16 |
| 2026-02-08 12:00 |
21:52:22.25 |
-15:35:24.5 |
HIP 108078 |
23.69 |
| 2026-02-09 00:00 |
21:52:24.08 |
-15:35:15.3 |
HIP 108078 |
23.23 |
| 2026-02-09 12:00 |
21:52:25.91 |
-15:35:06.1 |
HIP 108078 |
22.76 |
| 2026-02-10 00:00 |
21:52:27.74 |
-15:34:56.9 |
HIP 108078 |
22.30 |
| 2026-02-10 12:00 |
21:52:29.57 |
-15:34:47.7 |
HIP 108078 |
21.83 |
| 2026-02-11 00:00 |
21:52:31.41 |
-15:34:38.6 |
HIP 108078 |
21.37 |
| 2026-02-11 12:00 |
21:52:33.24 |
-15:34:29.4 |
HIP 108078 |
20.91 |
| 2026-02-12 00:00 |
21:52:35.08 |
-15:34:20.2 |
HIP 108078 |
20.44 |
| 2026-02-12 12:00 |
21:52:36.91 |
-15:34:11.0 |
HIP 108078 |
19.98 |
| 2026-02-13 00:00 |
21:52:38.75 |
-15:34:01.9 |
HIP 108078 |
19.51 |
| 2026-02-13 12:00 |
21:52:40.59 |
-15:33:52.7 |
HIP 108078 |
19.05 |
| 2026-02-14 00:00 |
21:52:42.42 |
-15:33:43.6 |
HIP 108078 |
18.58 |
| 2026-02-14 12:00 |
21:52:44.26 |
-15:33:34.4 |
HIP 108078 |
18.12 |
| 2026-02-15 00:00 |
21:52:46.10 |
-15:33:25.3 |
HIP 108078 |
17.65 |
| 2026-02-15 12:00 |
21:52:47.94 |
-15:33:16.2 |
HIP 108078 |
17.19 |
| 2026-02-16 00:00 |
21:52:49.77 |
-15:33:07.1 |
HIP 108078 |
16.72 |
| 2026-02-16 12:00 |
21:52:51.61 |
-15:32:58.0 |
HIP 108078 |
16.26 |
| 2026-02-17 00:00 |
21:52:53.45 |
-15:32:48.9 |
HIP 108078 |
15.80 |
| 2026-02-17 12:00 |
21:52:55.28 |
-15:32:39.8 |
HIP 108078 |
15.34 |
| 2026-02-18 00:00 |
21:52:57.12 |
-15:32:30.8 |
HIP 108078 |
14.87 |
| 2026-02-18 12:00 |
21:52:58.95 |
-15:32:21.8 |
HIP 108078 |
14.41 |
| 2026-02-19 00:00 |
21:53:00.78 |
-15:32:12.7 |
HIP 108078 |
13.95 |
| 2026-02-19 12:00 |
21:53:02.62 |
-15:32:03.7 |
HIP 108078 |
13.49 |
| 2026-02-20 00:00 |
21:53:04.45 |
-15:31:54.7 |
HIP 108078 |
13.04 |
| 2026-02-20 12:00 |
21:53:06.27 |
-15:31:45.8 |
HIP 108078 |
12.58 |
| 2026-02-21 00:00 |
21:53:08.10 |
-15:31:36.8 |
HIP 108078 |
12.12 |
| 2026-02-21 12:00 |
21:53:09.93 |
-15:31:27.9 |
HIP 108078 |
11.67 |
| 2026-02-22 00:00 |
21:53:11.75 |
-15:31:19.0 |
HIP 108078 |
11.21 |
| 2026-02-22 12:00 |
21:53:13.57 |
-15:31:10.1 |
HIP 108078 |
10.76 |
| 2026-02-23 00:00 |
21:53:15.39 |
-15:31:01.2 |
HIP 108078 |
10.31 |
| 2026-02-23 12:00 |
21:53:17.21 |
-15:30:52.4 |
HIP 108078 |
9.86 |
| 2026-02-24 00:00 |
21:53:19.02 |
-15:30:43.6 |
HIP 108078 |
9.41 |