| 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 |
-1.9498 |
+1.190 |
| 2011-07-06 |
2011-10-24 |
+55.4826 |
-25.761 |
| 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) |
| 2026-09-20 00:00 |
04:06:08.97 |
-04:25:07.8 |
HIP 19061 |
27.17 |
| 2026-09-20 12:00 |
04:06:07.65 |
-04:25:32.5 |
HIP 19061 |
26.65 |
| 2026-09-21 00:00 |
04:06:06.30 |
-04:25:57.1 |
HIP 19061 |
26.12 |
| 2026-09-21 12:00 |
04:06:04.92 |
-04:26:21.8 |
HIP 19061 |
25.58 |
| 2026-09-22 00:00 |
04:06:03.51 |
-04:26:46.4 |
HIP 19061 |
25.05 |
| 2026-09-22 12:00 |
04:06:02.08 |
-04:27:11.1 |
HIP 19061 |
24.50 |
| 2026-09-23 00:00 |
04:06:00.61 |
-04:27:35.7 |
HIP 19061 |
23.96 |
| 2026-09-23 12:00 |
04:05:59.11 |
-04:28:00.3 |
HIP 19061 |
23.41 |
| 2026-09-24 00:00 |
04:05:57.59 |
-04:28:24.9 |
HIP 19061 |
22.85 |
| 2026-09-24 12:00 |
04:05:56.03 |
-04:28:49.5 |
HIP 19061 |
22.29 |
| 2026-09-25 00:00 |
04:05:54.45 |
-04:29:14.0 |
HIP 19061 |
21.73 |
| 2026-09-25 12:00 |
04:05:52.84 |
-04:29:38.6 |
HIP 19061 |
21.17 |
| 2026-09-26 00:00 |
04:05:51.20 |
-04:30:03.1 |
HIP 19061 |
20.60 |
| 2026-09-26 12:00 |
04:05:49.53 |
-04:30:27.6 |
HIP 19061 |
20.03 |
| 2026-09-27 00:00 |
04:05:47.84 |
-04:30:52.1 |
HIP 19061 |
19.46 |
| 2026-09-27 12:00 |
04:05:46.11 |
-04:31:16.6 |
HIP 19061 |
18.88 |
| 2026-09-28 00:00 |
04:05:44.36 |
-04:31:41.0 |
HIP 19061 |
18.30 |
| 2026-09-28 12:00 |
04:05:42.58 |
-04:32:05.4 |
HIP 19061 |
17.72 |
| 2026-09-29 00:00 |
04:05:40.77 |
-04:32:29.8 |
HIP 19061 |
17.14 |
| 2026-09-29 12:00 |
04:05:38.94 |
-04:32:54.1 |
HIP 19061 |
16.56 |
| 2026-09-30 00:00 |
04:05:37.07 |
-04:33:18.4 |
HIP 19061 |
15.97 |
| 2026-09-30 12:00 |
04:05:35.18 |
-04:33:42.7 |
HIP 19061 |
15.39 |
| 2026-10-01 00:00 |
04:05:33.26 |
-04:34:06.9 |
HIP 19061 |
14.80 |
| 2026-10-01 12:00 |
04:05:31.32 |
-04:34:31.1 |
HIP 19061 |
14.22 |
| 2026-10-02 00:00 |
04:05:29.35 |
-04:34:55.3 |
HIP 19061 |
13.64 |
| 2026-10-02 12:00 |
04:05:27.35 |
-04:35:19.4 |
HIP 19061 |
13.06 |
| 2026-10-03 00:00 |
04:05:25.32 |
-04:35:43.4 |
HIP 19061 |
12.48 |
| 2026-10-03 12:00 |
04:05:23.27 |
-04:36:07.4 |
HIP 19061 |
11.91 |
| 2026-10-04 00:00 |
04:05:21.19 |
-04:36:31.4 |
HIP 19061 |
11.35 |
| 2026-10-04 12:00 |
04:05:19.08 |
-04:36:55.3 |
HIP 19061 |
10.79 |
| 2026-10-05 00:00 |
04:05:16.95 |
-04:37:19.1 |
HIP 19061 |
10.25 |
| 2026-10-05 12:00 |
04:05:14.79 |
-04:37:42.9 |
HIP 19061 |
9.72 |
| 2026-10-06 00:00 |
04:05:12.60 |
-04:38:06.7 |
HIP 19061 |
9.21 |
| 2026-10-06 12:00 |
04:05:10.39 |
-04:38:30.3 |
HIP 19061 |
8.73 |
| 2026-10-07 00:00 |
04:05:08.16 |
-04:38:53.9 |
HIP 19061 |
8.26 |
| 2026-10-07 12:00 |
04:05:05.90 |
-04:39:17.5 |
HIP 19061 |
7.84 |
| 2026-10-08 00:00 |
04:05:03.61 |
-04:39:40.9 |
HIP 19061 |
7.45 |
| 2026-10-08 12:00 |
04:05:01.30 |
-04:40:04.3 |
HIP 19061 |
7.11 |
| 2026-10-09 00:00 |
04:04:58.96 |
-04:40:27.7 |
HIP 19061 |
6.83 |
| 2026-10-09 12:00 |
04:04:56.60 |
-04:40:50.9 |
HIP 19061 |
6.61 |
| 2026-10-10 00:00 |
04:04:54.21 |
-04:41:14.1 |
HIP 19061 |
6.47 |
| 2026-10-10 12:00 |
04:04:51.80 |
-04:41:37.2 |
HIP 19061 |
6.40 |
| 2026-10-11 00:00 |
04:04:49.37 |
-04:42:00.2 |
HIP 19061 |
6.42 |