| Parameter |
Value |
| Designation |
C/2004 G1 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2004-06-04T22:25:55.669440Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:40Z |
| Obs used |
48 |
| NEO |
- |
| M1 |
14.400 |
| K1 |
23.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2004-04-16.0000000 |
| e |
0.99627354 |
| q (au) |
1.201031 |
| a (au) |
322.298040 |
| i (deg) |
114.486194 |
| Ω (om, deg) |
228.344676 |
| ω (w, deg) |
110.604107 |
| M (ma, deg) |
359.991494 |
Magnitude
Scatter + Global Linear
$$
M_a = (16.162 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
16.162 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.800 |
| 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 |
| 2004-04-09 |
2004-05-15 |
+33.2977 |
-5.480 |
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 |
01:16:30.68 |
-71:15:22.9 |
HIP 6155 |
14.54 |
| 2026-05-12 12:00 |
01:16:37.48 |
-71:15:42.3 |
HIP 6155 |
14.29 |
| 2026-05-13 00:00 |
01:16:44.25 |
-71:16:01.9 |
HIP 6155 |
14.07 |
| 2026-05-13 12:00 |
01:16:50.99 |
-71:16:21.8 |
HIP 6155 |
13.88 |
| 2026-05-14 00:00 |
01:16:57.69 |
-71:16:42.1 |
HIP 6155 |
13.73 |
| 2026-05-14 12:00 |
01:17:04.37 |
-71:17:02.6 |
HIP 6155 |
13.61 |
| 2026-05-15 00:00 |
01:17:11.01 |
-71:17:23.4 |
HIP 6155 |
13.52 |
| 2026-05-15 12:00 |
01:17:17.62 |
-71:17:44.6 |
HIP 6155 |
13.47 |
| 2026-05-16 00:00 |
01:17:24.20 |
-71:18:06.0 |
HIP 6155 |
13.45 |
| 2026-05-16 12:00 |
01:17:30.74 |
-71:18:27.7 |
HIP 6155 |
13.47 |
| 2026-05-17 00:00 |
01:17:37.25 |
-71:18:49.7 |
HIP 6155 |
13.53 |
| 2026-05-17 12:00 |
01:17:43.73 |
-71:19:12.0 |
HIP 6155 |
13.62 |
| 2026-05-18 00:00 |
01:17:50.17 |
-71:19:34.5 |
HIP 6155 |
13.75 |
| 2026-05-18 12:00 |
01:17:56.57 |
-71:19:57.4 |
HIP 6155 |
13.91 |
| 2026-05-19 00:00 |
01:18:02.94 |
-71:20:20.6 |
HIP 6155 |
14.10 |
| 2026-05-19 12:00 |
01:18:09.27 |
-71:20:44.0 |
HIP 6155 |
14.33 |
| 2026-05-20 00:00 |
01:18:15.57 |
-71:21:07.7 |
HIP 6155 |
14.58 |
| 2026-05-20 12:00 |
01:18:21.83 |
-71:21:31.7 |
HIP 6155 |
14.87 |
| 2026-05-21 00:00 |
01:18:28.05 |
-71:21:56.0 |
HIP 6155 |
15.18 |
| 2026-05-21 12:00 |
01:18:34.23 |
-71:22:20.5 |
HIP 6155 |
15.51 |
| 2026-05-22 00:00 |
01:18:40.38 |
-71:22:45.3 |
HIP 6155 |
15.87 |
| 2026-05-22 12:00 |
01:18:46.48 |
-71:23:10.4 |
HIP 6155 |
16.26 |
| 2026-05-23 00:00 |
01:18:52.55 |
-71:23:35.8 |
HIP 6155 |
16.66 |
| 2026-05-23 12:00 |
01:18:58.57 |
-71:24:01.4 |
HIP 6155 |
17.08 |
| 2026-05-24 00:00 |
01:19:04.56 |
-71:24:27.3 |
HIP 6155 |
17.52 |
| 2026-05-24 12:00 |
01:19:10.51 |
-71:24:53.5 |
HIP 6155 |
17.98 |
| 2026-05-25 00:00 |
01:19:16.41 |
-71:25:19.9 |
HIP 6155 |
18.45 |
| 2026-05-25 12:00 |
01:19:22.28 |
-71:25:46.6 |
HIP 6155 |
18.94 |
| 2026-05-26 00:00 |
01:19:28.10 |
-71:26:13.6 |
HIP 6155 |
19.44 |
| 2026-05-26 12:00 |
01:19:33.88 |
-71:26:40.8 |
HIP 6155 |
19.95 |
| 2026-05-27 00:00 |
01:19:39.62 |
-71:27:08.3 |
HIP 6155 |
20.48 |
| 2026-05-27 12:00 |
01:19:45.32 |
-71:27:36.0 |
HIP 6218 |
20.57 |
| 2026-05-28 00:00 |
01:19:50.97 |
-71:28:04.0 |
HIP 6218 |
20.11 |
| 2026-05-28 12:00 |
01:19:56.58 |
-71:28:32.2 |
HIP 6218 |
19.66 |
| 2026-05-29 00:00 |
01:20:02.15 |
-71:29:00.7 |
HIP 6218 |
19.22 |
| 2026-05-29 12:00 |
01:20:07.67 |
-71:29:29.4 |
HIP 6218 |
18.78 |
| 2026-05-30 00:00 |
01:20:13.15 |
-71:29:58.4 |
HIP 6218 |
18.35 |
| 2026-05-30 12:00 |
01:20:18.58 |
-71:30:27.7 |
HIP 6218 |
17.93 |
| 2026-05-31 00:00 |
01:20:23.97 |
-71:30:57.1 |
HIP 6218 |
17.52 |
| 2026-05-31 12:00 |
01:20:29.32 |
-71:31:26.8 |
HIP 6218 |
17.12 |
| 2026-06-01 00:00 |
01:20:34.61 |
-71:31:56.8 |
HIP 6218 |
16.72 |
| 2026-06-01 12:00 |
01:20:39.87 |
-71:32:27.0 |
HIP 6218 |
16.34 |
| 2026-06-02 00:00 |
01:20:45.07 |
-71:32:57.4 |
HIP 6218 |
15.98 |