| Parameter |
Value |
| Designation |
C/1986 V1 (Sorrells) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1987-03-09T15:47:46.700160Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:33Z |
| Obs used |
360 |
| NEO |
- |
| M1 |
5.500 |
| K1 |
13.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1987-02-24.0000000 |
| e |
0.99992595 |
| q (au) |
1.721158 |
| a (au) |
23244.336024 |
| i (deg) |
160.579825 |
| Ω (om, deg) |
74.802450 |
| ω (w, deg) |
70.233014 |
| M (ma, deg) |
359.999996 |
Magnitude
Scatter + Global Linear
$$
M_a = (3.512 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
3.512 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 1986-11-02 |
1986-12-29 |
+9.0293 |
-2.778 |
| 1986-12-29 |
1987-02-28 |
-7.9512 |
+1.990 |
| 1987-04-11 |
1987-09-20 |
-0.2477 |
-0.077 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
13:06:54.86 |
-23:35:23.1 |
HIP 64095 |
16.59 |
| 2026-06-01 12:00 |
13:06:53.64 |
-23:35:10.4 |
HIP 64095 |
16.87 |
| 2026-06-02 00:00 |
13:06:52.43 |
-23:34:57.7 |
HIP 64095 |
17.15 |
| 2026-06-02 12:00 |
13:06:51.24 |
-23:34:45.0 |
HIP 64095 |
17.43 |
| 2026-06-03 00:00 |
13:06:50.06 |
-23:34:32.4 |
HIP 64095 |
17.71 |
| 2026-06-03 12:00 |
13:06:48.89 |
-23:34:19.8 |
HIP 64095 |
17.99 |
| 2026-06-04 00:00 |
13:06:47.73 |
-23:34:07.3 |
HIP 64095 |
18.27 |
| 2026-06-04 12:00 |
13:06:46.59 |
-23:33:54.7 |
HIP 64095 |
18.54 |
| 2026-06-05 00:00 |
13:06:45.46 |
-23:33:42.3 |
HIP 64095 |
18.82 |
| 2026-06-05 12:00 |
13:06:44.35 |
-23:33:29.8 |
HIP 64095 |
19.09 |
| 2026-06-06 00:00 |
13:06:43.25 |
-23:33:17.4 |
HIP 64095 |
19.36 |
| 2026-06-06 12:00 |
13:06:42.16 |
-23:33:05.0 |
HIP 64095 |
19.63 |
| 2026-06-07 00:00 |
13:06:41.08 |
-23:32:52.7 |
HIP 64095 |
19.90 |
| 2026-06-07 12:00 |
13:06:40.02 |
-23:32:40.4 |
HIP 64095 |
20.17 |
| 2026-06-08 00:00 |
13:06:38.98 |
-23:32:28.1 |
HIP 64095 |
20.43 |
| 2026-06-08 12:00 |
13:06:37.94 |
-23:32:15.9 |
HIP 64095 |
20.70 |
| 2026-06-09 00:00 |
13:06:36.92 |
-23:32:03.7 |
HIP 64095 |
20.96 |
| 2026-06-09 12:00 |
13:06:35.92 |
-23:31:51.6 |
HIP 64095 |
21.22 |
| 2026-06-10 00:00 |
13:06:34.93 |
-23:31:39.5 |
HIP 64095 |
21.48 |
| 2026-06-10 12:00 |
13:06:33.95 |
-23:31:27.4 |
HIP 64095 |
21.73 |
| 2026-06-11 00:00 |
13:06:32.99 |
-23:31:15.4 |
HIP 64095 |
21.99 |
| 2026-06-11 12:00 |
13:06:32.04 |
-23:31:03.5 |
HIP 64095 |
22.24 |
| 2026-06-12 00:00 |
13:06:31.11 |
-23:30:51.6 |
HIP 64095 |
22.49 |
| 2026-06-12 12:00 |
13:06:30.19 |
-23:30:39.7 |
HIP 64095 |
22.73 |
| 2026-06-13 00:00 |
13:06:29.28 |
-23:30:27.9 |
HIP 64095 |
22.98 |
| 2026-06-13 12:00 |
13:06:28.39 |
-23:30:16.2 |
HIP 64095 |
23.22 |
| 2026-06-14 00:00 |
13:06:27.52 |
-23:30:04.5 |
HIP 64095 |
23.46 |
| 2026-06-14 12:00 |
13:06:26.66 |
-23:29:52.8 |
HIP 64095 |
23.69 |
| 2026-06-15 00:00 |
13:06:25.81 |
-23:29:41.2 |
HIP 64095 |
23.93 |
| 2026-06-15 12:00 |
13:06:24.98 |
-23:29:29.7 |
HIP 64095 |
24.16 |
| 2026-06-16 00:00 |
13:06:24.16 |
-23:29:18.2 |
HIP 64095 |
24.39 |
| 2026-06-16 12:00 |
13:06:23.36 |
-23:29:06.8 |
HIP 64095 |
24.61 |
| 2026-06-17 00:00 |
13:06:22.57 |
-23:28:55.4 |
HIP 64095 |
24.84 |
| 2026-06-17 12:00 |
13:06:21.80 |
-23:28:44.1 |
HIP 64095 |
25.06 |
| 2026-06-18 00:00 |
13:06:21.05 |
-23:28:32.8 |
HIP 64095 |
25.27 |
| 2026-06-18 12:00 |
13:06:20.30 |
-23:28:21.6 |
HIP 64095 |
25.49 |
| 2026-06-19 00:00 |
13:06:19.58 |
-23:28:10.5 |
HIP 64095 |
25.70 |
| 2026-06-19 12:00 |
13:06:18.87 |
-23:27:59.4 |
HIP 64095 |
25.91 |
| 2026-06-20 00:00 |
13:06:18.17 |
-23:27:48.4 |
HIP 64095 |
26.11 |
| 2026-06-20 12:00 |
13:06:17.49 |
-23:27:37.4 |
HIP 64095 |
26.32 |
| 2026-06-21 00:00 |
13:06:16.82 |
-23:27:26.5 |
HIP 64095 |
26.52 |
| 2026-06-21 12:00 |
13:06:16.17 |
-23:27:15.7 |
HIP 64095 |
26.71 |
| 2026-06-22 00:00 |
13:06:15.54 |
-23:27:04.9 |
HIP 64095 |
26.91 |