C/2004 G1 (LINEAR)
| 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) |
| 2026-02-03 00:00 |
00:54:10.17 |
-71:52:12.9 |
HIP 4341 |
24.74 |
| 2026-02-03 12:00 |
00:54:14.08 |
-71:51:36.3 |
HIP 4341 |
24.07 |
| 2026-02-04 00:00 |
00:54:18.06 |
-71:50:59.8 |
HIP 4341 |
23.40 |
| 2026-02-04 12:00 |
00:54:22.10 |
-71:50:23.4 |
HIP 4341 |
22.73 |
| 2026-02-05 00:00 |
00:54:26.19 |
-71:49:47.2 |
HIP 4341 |
22.06 |
| 2026-02-05 12:00 |
00:54:30.34 |
-71:49:11.2 |
HIP 4341 |
21.40 |
| 2026-02-06 00:00 |
00:54:34.55 |
-71:48:35.3 |
HIP 4341 |
20.74 |
| 2026-02-06 12:00 |
00:54:38.82 |
-71:47:59.5 |
HIP 4341 |
20.08 |
| 2026-02-07 00:00 |
00:54:43.14 |
-71:47:24.0 |
HIP 4341 |
19.42 |
| 2026-02-07 12:00 |
00:54:47.52 |
-71:46:48.6 |
HIP 4341 |
18.77 |
| 2026-02-08 00:00 |
00:54:51.95 |
-71:46:13.4 |
HIP 4341 |
18.12 |
| 2026-02-08 12:00 |
00:54:56.44 |
-71:45:38.3 |
HIP 4341 |
17.48 |
| 2026-02-09 00:00 |
00:55:00.99 |
-71:45:03.4 |
HIP 4341 |
16.84 |
| 2026-02-09 12:00 |
00:55:05.59 |
-71:44:28.7 |
HIP 4341 |
16.20 |
| 2026-02-10 00:00 |
00:55:10.25 |
-71:43:54.2 |
HIP 4341 |
15.58 |
| 2026-02-10 12:00 |
00:55:14.95 |
-71:43:19.9 |
HIP 4341 |
14.96 |
| 2026-02-11 00:00 |
00:55:19.72 |
-71:42:45.7 |
HIP 4341 |
14.35 |
| 2026-02-11 12:00 |
00:55:24.53 |
-71:42:11.7 |
HIP 4341 |
13.74 |
| 2026-02-12 00:00 |
00:55:29.40 |
-71:41:37.9 |
HIP 4341 |
13.15 |
| 2026-02-12 12:00 |
00:55:34.32 |
-71:41:04.3 |
HIP 4341 |
12.57 |
| 2026-02-13 00:00 |
00:55:39.30 |
-71:40:30.9 |
HIP 4341 |
12.01 |
| 2026-02-13 12:00 |
00:55:44.32 |
-71:39:57.7 |
HIP 4341 |
11.46 |
| 2026-02-14 00:00 |
00:55:49.40 |
-71:39:24.7 |
HIP 4341 |
10.93 |
| 2026-02-14 12:00 |
00:55:54.52 |
-71:38:51.9 |
HIP 4341 |
10.42 |
| 2026-02-15 00:00 |
00:55:59.70 |
-71:38:19.3 |
HIP 4341 |
9.93 |
| 2026-02-15 12:00 |
00:56:04.92 |
-71:37:46.9 |
HIP 4341 |
9.47 |
| 2026-02-16 00:00 |
00:56:10.20 |
-71:37:14.7 |
HIP 4341 |
9.05 |
| 2026-02-16 12:00 |
00:56:15.52 |
-71:36:42.7 |
HIP 4341 |
8.66 |
| 2026-02-17 00:00 |
00:56:20.90 |
-71:36:10.9 |
HIP 4341 |
8.32 |
| 2026-02-17 12:00 |
00:56:26.32 |
-71:35:39.4 |
HIP 4341 |
8.02 |
| 2026-02-18 00:00 |
00:56:31.79 |
-71:35:08.1 |
HIP 4341 |
7.78 |
| 2026-02-18 12:00 |
00:56:37.30 |
-71:34:36.9 |
HIP 4341 |
7.59 |
| 2026-02-19 00:00 |
00:56:42.86 |
-71:34:06.0 |
HIP 4341 |
7.47 |
| 2026-02-19 12:00 |
00:56:48.47 |
-71:33:35.4 |
HIP 4341 |
7.41 |
| 2026-02-20 00:00 |
00:56:54.13 |
-71:33:04.9 |
HIP 4341 |
7.42 |
| 2026-02-20 12:00 |
00:56:59.82 |
-71:32:34.7 |
HIP 4341 |
7.50 |
| 2026-02-21 00:00 |
00:57:05.57 |
-71:32:04.7 |
HIP 4341 |
7.64 |
| 2026-02-21 12:00 |
00:57:11.36 |
-71:31:35.0 |
HIP 4341 |
7.84 |
| 2026-02-22 00:00 |
00:57:17.19 |
-71:31:05.4 |
HIP 4341 |
8.10 |
| 2026-02-22 12:00 |
00:57:23.06 |
-71:30:36.1 |
HIP 4341 |
8.41 |
| 2026-02-23 00:00 |
00:57:28.98 |
-71:30:07.1 |
HIP 4341 |
8.77 |
| 2026-02-23 12:00 |
00:57:34.93 |
-71:29:38.3 |
HIP 4341 |
9.16 |
| 2026-02-24 00:00 |
00:57:40.93 |
-71:29:09.7 |
HIP 4341 |
9.59 |