| Parameter |
Value |
| Designation |
C/2007 E1 (Garradd) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2007-05-23T19:56:03.209280Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:05Z |
| Obs used |
1017 |
| NEO |
- |
| M1 |
13.900 |
| K1 |
9.250 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2007-05-21.0000000 |
| e |
0.98021742 |
| q (au) |
1.285863 |
| a (au) |
64.999734 |
| i (deg) |
174.393993 |
| Ω (om, deg) |
153.826639 |
| ω (w, deg) |
7.102013 |
| M (ma, deg) |
359.994676 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.954 + 4.197\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.954 |
| n |
4.197 |
| gf |
1.000 |
| gb |
-0.945 |
| 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 |
| 2007-03-13 |
2007-05-20 |
+25.1523 |
-4.738 |
| 2007-05-26 |
2007-12-27 |
+6.4556 |
-2.958 |
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 |
23:09:17.14 |
-04:15:21.9 |
HIP 114355 |
18.29 |
| 2026-06-01 12:00 |
23:09:17.32 |
-04:15:20.0 |
HIP 114355 |
18.25 |
| 2026-06-02 00:00 |
23:09:17.48 |
-04:15:18.2 |
HIP 114355 |
18.21 |
| 2026-06-02 12:00 |
23:09:17.62 |
-04:15:16.6 |
HIP 114355 |
18.18 |
| 2026-06-03 00:00 |
23:09:17.73 |
-04:15:15.1 |
HIP 114355 |
18.15 |
| 2026-06-03 12:00 |
23:09:17.81 |
-04:15:13.8 |
HIP 114355 |
18.12 |
| 2026-06-04 00:00 |
23:09:17.87 |
-04:15:12.7 |
HIP 114355 |
18.10 |
| 2026-06-04 12:00 |
23:09:17.91 |
-04:15:11.7 |
HIP 114355 |
18.08 |
| 2026-06-05 00:00 |
23:09:17.91 |
-04:15:10.9 |
HIP 114355 |
18.06 |
| 2026-06-05 12:00 |
23:09:17.90 |
-04:15:10.2 |
HIP 114355 |
18.06 |
| 2026-06-06 00:00 |
23:09:17.86 |
-04:15:09.7 |
HIP 114355 |
18.05 |
| 2026-06-06 12:00 |
23:09:17.79 |
-04:15:09.4 |
HIP 114355 |
18.05 |
| 2026-06-07 00:00 |
23:09:17.70 |
-04:15:09.2 |
HIP 114355 |
18.05 |
| 2026-06-07 12:00 |
23:09:17.58 |
-04:15:09.1 |
HIP 114355 |
18.06 |
| 2026-06-08 00:00 |
23:09:17.44 |
-04:15:09.3 |
HIP 114355 |
18.07 |
| 2026-06-08 12:00 |
23:09:17.27 |
-04:15:09.6 |
HIP 114355 |
18.09 |
| 2026-06-09 00:00 |
23:09:17.08 |
-04:15:10.0 |
HIP 114355 |
18.11 |
| 2026-06-09 12:00 |
23:09:16.86 |
-04:15:10.6 |
HIP 114355 |
18.13 |
| 2026-06-10 00:00 |
23:09:16.62 |
-04:15:11.4 |
HIP 114355 |
18.16 |
| 2026-06-10 12:00 |
23:09:16.35 |
-04:15:12.3 |
HIP 114355 |
18.19 |
| 2026-06-11 00:00 |
23:09:16.06 |
-04:15:13.4 |
HIP 114355 |
18.23 |
| 2026-06-11 12:00 |
23:09:15.74 |
-04:15:14.6 |
HIP 114355 |
18.27 |
| 2026-06-12 00:00 |
23:09:15.39 |
-04:15:16.0 |
HIP 114355 |
18.32 |
| 2026-06-12 12:00 |
23:09:15.02 |
-04:15:17.6 |
HIP 114355 |
18.37 |
| 2026-06-13 00:00 |
23:09:14.63 |
-04:15:19.3 |
HIP 114355 |
18.43 |
| 2026-06-13 12:00 |
23:09:14.20 |
-04:15:21.2 |
HIP 114355 |
18.49 |
| 2026-06-14 00:00 |
23:09:13.76 |
-04:15:23.2 |
HIP 114355 |
18.56 |
| 2026-06-14 12:00 |
23:09:13.29 |
-04:15:25.4 |
HIP 114355 |
18.63 |
| 2026-06-15 00:00 |
23:09:12.79 |
-04:15:27.8 |
HIP 114355 |
18.71 |
| 2026-06-15 12:00 |
23:09:12.27 |
-04:15:30.3 |
HIP 114355 |
18.79 |
| 2026-06-16 00:00 |
23:09:11.72 |
-04:15:33.0 |
HIP 114355 |
18.87 |
| 2026-06-16 12:00 |
23:09:11.14 |
-04:15:35.9 |
HIP 114355 |
18.97 |
| 2026-06-17 00:00 |
23:09:10.54 |
-04:15:38.9 |
HIP 114355 |
19.06 |
| 2026-06-17 12:00 |
23:09:09.92 |
-04:15:42.1 |
HIP 114355 |
19.17 |
| 2026-06-18 00:00 |
23:09:09.27 |
-04:15:45.4 |
HIP 114355 |
19.28 |
| 2026-06-18 12:00 |
23:09:08.60 |
-04:15:48.9 |
HIP 114355 |
19.39 |
| 2026-06-19 00:00 |
23:09:07.90 |
-04:15:52.5 |
HIP 114355 |
19.51 |
| 2026-06-19 12:00 |
23:09:07.17 |
-04:15:56.3 |
HIP 114355 |
19.64 |
| 2026-06-20 00:00 |
23:09:06.42 |
-04:16:00.3 |
HIP 114355 |
19.77 |
| 2026-06-20 12:00 |
23:09:05.64 |
-04:16:04.4 |
HIP 114325 |
19.90 |
| 2026-06-21 00:00 |
23:09:04.84 |
-04:16:08.7 |
HIP 114325 |
20.00 |
| 2026-06-21 12:00 |
23:09:04.02 |
-04:16:13.2 |
HIP 114325 |
20.10 |
| 2026-06-22 00:00 |
23:09:03.17 |
-04:16:17.8 |
HIP 114325 |
20.20 |