| Parameter |
Value |
| Designation |
C/2011 A3 (Gibbs) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2011-12-16T02:06:29.868480Z |
| Orbit solution date (soln_date, UTC) |
2021-04-16T12:05:53Z |
| Obs used |
1747 |
| NEO |
- |
| M1 |
9.900 |
| K1 |
8.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2011-07-07.0000000 |
| e |
0.99799388 |
| q (au) |
2.344841 |
| a (au) |
1168.845517 |
| i (deg) |
26.074353 |
| Ω (om, deg) |
124.895272 |
| ω (w, deg) |
141.161078 |
| M (ma, deg) |
359.996002 |
Magnitude
Scatter + Global Linear
$$
M_a = (7.606 + 4.476\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.606 |
| n |
4.476 |
| gf |
1.000 |
| gb |
-1.000 |
| 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 |
| 2011-01-15 |
2011-07-06 |
-1.9497 |
+1.190 |
| 2011-07-06 |
2011-10-24 |
+55.4815 |
-25.760 |
| 2012-03-05 |
2012-09-09 |
-0.6396 |
-0.001 |
| 2012-09-09 |
2013-10-06 |
-6.5562 |
+2.870 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
03:57:08.01 |
-03:48:50.6 |
HIP 18588 |
24.66 |
| 2026-05-12 12:00 |
03:57:11.80 |
-03:48:35.0 |
HIP 18588 |
23.68 |
| 2026-05-13 00:00 |
03:57:15.58 |
-03:48:19.5 |
HIP 18588 |
22.71 |
| 2026-05-13 12:00 |
03:57:19.38 |
-03:48:04.3 |
HIP 18588 |
21.74 |
| 2026-05-14 00:00 |
03:57:23.17 |
-03:47:49.2 |
HIP 18588 |
20.77 |
| 2026-05-14 12:00 |
03:57:26.97 |
-03:47:34.3 |
HIP 18588 |
19.80 |
| 2026-05-15 00:00 |
03:57:30.78 |
-03:47:19.5 |
HIP 18588 |
18.83 |
| 2026-05-15 12:00 |
03:57:34.59 |
-03:47:05.0 |
HIP 18588 |
17.86 |
| 2026-05-16 00:00 |
03:57:38.40 |
-03:46:50.6 |
HIP 18588 |
16.89 |
| 2026-05-16 12:00 |
03:57:42.21 |
-03:46:36.4 |
HIP 18588 |
15.93 |
| 2026-05-17 00:00 |
03:57:46.03 |
-03:46:22.4 |
HIP 18588 |
14.97 |
| 2026-05-17 12:00 |
03:57:49.85 |
-03:46:08.6 |
HIP 18588 |
14.01 |
| 2026-05-18 00:00 |
03:57:53.67 |
-03:45:55.0 |
HIP 18588 |
13.06 |
| 2026-05-18 12:00 |
03:57:57.49 |
-03:45:41.5 |
HIP 18588 |
12.11 |
| 2026-05-19 00:00 |
03:58:01.32 |
-03:45:28.3 |
HIP 18588 |
11.17 |
| 2026-05-19 12:00 |
03:58:05.15 |
-03:45:15.2 |
HIP 18588 |
10.24 |
| 2026-05-20 00:00 |
03:58:08.97 |
-03:45:02.3 |
HIP 18588 |
9.31 |
| 2026-05-20 12:00 |
03:58:12.80 |
-03:44:49.6 |
HIP 18588 |
8.41 |
| 2026-05-21 00:00 |
03:58:16.63 |
-03:44:37.1 |
HIP 18588 |
7.52 |
| 2026-05-21 12:00 |
03:58:20.46 |
-03:44:24.8 |
HIP 18588 |
6.66 |
| 2026-05-22 00:00 |
03:58:24.30 |
-03:44:12.6 |
HIP 18588 |
5.84 |
| 2026-05-22 12:00 |
03:58:28.13 |
-03:44:00.7 |
HIP 18588 |
5.08 |
| 2026-05-23 00:00 |
03:58:31.96 |
-03:43:49.0 |
HIP 18588 |
4.41 |
| 2026-05-23 12:00 |
03:58:35.79 |
-03:43:37.4 |
HIP 18588 |
3.87 |
| 2026-05-24 00:00 |
03:58:39.62 |
-03:43:26.1 |
HIP 18588 |
3.53 |
| 2026-05-24 12:00 |
03:58:43.45 |
-03:43:14.9 |
HIP 18588 |
3.44 |
| 2026-05-25 00:00 |
03:58:47.27 |
-03:43:03.9 |
HIP 18588 |
3.62 |
| 2026-05-25 12:00 |
03:58:51.10 |
-03:42:53.1 |
HIP 18588 |
4.04 |
| 2026-05-26 00:00 |
03:58:54.92 |
-03:42:42.5 |
HIP 18588 |
4.63 |
| 2026-05-26 12:00 |
03:58:58.75 |
-03:42:32.1 |
HIP 18588 |
5.33 |
| 2026-05-27 00:00 |
03:59:02.57 |
-03:42:21.9 |
HIP 18588 |
6.11 |
| 2026-05-27 12:00 |
03:59:06.39 |
-03:42:11.9 |
HIP 18588 |
6.94 |
| 2026-05-28 00:00 |
03:59:10.20 |
-03:42:02.1 |
HIP 18588 |
7.80 |
| 2026-05-28 12:00 |
03:59:14.01 |
-03:41:52.5 |
HIP 18588 |
8.68 |
| 2026-05-29 00:00 |
03:59:17.82 |
-03:41:43.1 |
HIP 18588 |
9.57 |
| 2026-05-29 12:00 |
03:59:21.63 |
-03:41:33.9 |
HIP 18588 |
10.48 |
| 2026-05-30 00:00 |
03:59:25.44 |
-03:41:24.8 |
HIP 18588 |
11.40 |
| 2026-05-30 12:00 |
03:59:29.24 |
-03:41:16.0 |
HIP 18588 |
12.32 |
| 2026-05-31 00:00 |
03:59:33.03 |
-03:41:07.4 |
HIP 18588 |
13.25 |
| 2026-05-31 12:00 |
03:59:36.83 |
-03:40:59.0 |
HIP 18588 |
14.18 |
| 2026-06-01 00:00 |
03:59:40.61 |
-03:40:50.7 |
HIP 18588 |
15.12 |
| 2026-06-01 12:00 |
03:59:44.40 |
-03:40:42.7 |
HIP 18588 |
16.05 |
| 2026-06-02 00:00 |
03:59:48.18 |
-03:40:34.9 |
HIP 18588 |
16.99 |