| Parameter |
Value |
| Designation |
C/1999 G1 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1998-08-01T15:27:45.645120Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:57Z |
| Obs used |
76 |
| NEO |
- |
| M1 |
8.000 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1999-04-12.0000000 |
| e |
0.85677293 |
| q (au) |
4.048556 |
| a (au) |
28.266698 |
| i (deg) |
76.568197 |
| Ω (om, deg) |
23.462057 |
| ω (w, deg) |
136.125424 |
| M (ma, deg) |
1.661583 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.053 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.053 |
| n |
2.000 |
| gf |
0.965 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
9.943 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
02:13:55.50 |
-54:00:41.5 |
HIP 10246 |
18.81 |
| 2026-03-26 12:00 |
02:13:59.72 |
-54:00:10.4 |
HIP 10301 |
19.21 |
| 2026-03-27 00:00 |
02:14:03.96 |
-53:59:39.6 |
HIP 10301 |
19.18 |
| 2026-03-27 12:00 |
02:14:08.21 |
-53:59:09.1 |
HIP 10301 |
19.19 |
| 2026-03-28 00:00 |
02:14:12.49 |
-53:58:38.9 |
HIP 10301 |
19.24 |
| 2026-03-28 12:00 |
02:14:16.78 |
-53:58:09.0 |
HIP 10301 |
19.33 |
| 2026-03-29 00:00 |
02:14:21.10 |
-53:57:39.3 |
HIP 10301 |
19.46 |
| 2026-03-29 12:00 |
02:14:25.43 |
-53:57:10.0 |
HIP 10301 |
19.62 |
| 2026-03-30 00:00 |
02:14:29.78 |
-53:56:41.0 |
HIP 10301 |
19.82 |
| 2026-03-30 12:00 |
02:14:34.15 |
-53:56:12.3 |
HIP 10301 |
20.06 |
| 2026-03-31 00:00 |
02:14:38.54 |
-53:55:43.9 |
HIP 10301 |
20.33 |
| 2026-03-31 12:00 |
02:14:42.94 |
-53:55:15.7 |
HIP 10301 |
20.64 |
| 2026-04-01 00:00 |
02:14:47.36 |
-53:54:47.9 |
HIP 10650 |
20.82 |
| 2026-04-01 12:00 |
02:14:51.79 |
-53:54:20.4 |
HIP 10650 |
20.08 |
| 2026-04-02 00:00 |
02:14:56.25 |
-53:53:53.2 |
HIP 10650 |
19.33 |
| 2026-04-02 12:00 |
02:15:00.71 |
-53:53:26.3 |
HIP 10650 |
18.59 |
| 2026-04-03 00:00 |
02:15:05.20 |
-53:52:59.7 |
HIP 10650 |
17.86 |
| 2026-04-03 12:00 |
02:15:09.70 |
-53:52:33.5 |
HIP 10650 |
17.13 |
| 2026-04-04 00:00 |
02:15:14.21 |
-53:52:07.5 |
HIP 10650 |
16.40 |
| 2026-04-04 12:00 |
02:15:18.74 |
-53:51:41.9 |
HIP 10650 |
15.68 |
| 2026-04-05 00:00 |
02:15:23.29 |
-53:51:16.5 |
HIP 10650 |
14.96 |
| 2026-04-05 12:00 |
02:15:27.84 |
-53:50:51.5 |
HIP 10650 |
14.25 |
| 2026-04-06 00:00 |
02:15:32.41 |
-53:50:26.8 |
HIP 10650 |
13.54 |
| 2026-04-06 12:00 |
02:15:37.00 |
-53:50:02.4 |
HIP 10650 |
12.85 |
| 2026-04-07 00:00 |
02:15:41.60 |
-53:49:38.4 |
HIP 10650 |
12.16 |
| 2026-04-07 12:00 |
02:15:46.21 |
-53:49:14.6 |
HIP 10650 |
11.48 |
| 2026-04-08 00:00 |
02:15:50.84 |
-53:48:51.2 |
HIP 10650 |
10.82 |
| 2026-04-08 12:00 |
02:15:55.47 |
-53:48:28.1 |
HIP 10650 |
10.17 |
| 2026-04-09 00:00 |
02:16:00.12 |
-53:48:05.3 |
HIP 10650 |
9.54 |
| 2026-04-09 12:00 |
02:16:04.78 |
-53:47:42.9 |
HIP 10650 |
8.93 |
| 2026-04-10 00:00 |
02:16:09.46 |
-53:47:20.8 |
HIP 10650 |
8.35 |
| 2026-04-10 12:00 |
02:16:14.14 |
-53:46:59.0 |
HIP 10650 |
7.79 |
| 2026-04-11 00:00 |
02:16:18.83 |
-53:46:37.5 |
HIP 10650 |
7.28 |
| 2026-04-11 12:00 |
02:16:23.54 |
-53:46:16.4 |
HIP 10650 |
6.81 |
| 2026-04-12 00:00 |
02:16:28.26 |
-53:45:55.6 |
HIP 10650 |
6.39 |
| 2026-04-12 12:00 |
02:16:32.98 |
-53:45:35.2 |
HIP 10650 |
6.05 |
| 2026-04-13 00:00 |
02:16:37.72 |
-53:45:15.0 |
HIP 10650 |
5.78 |
| 2026-04-13 12:00 |
02:16:42.46 |
-53:44:55.3 |
HIP 10650 |
5.60 |
| 2026-04-14 00:00 |
02:16:47.21 |
-53:44:35.8 |
HIP 10650 |
5.53 |
| 2026-04-14 12:00 |
02:16:51.98 |
-53:44:16.7 |
HIP 10650 |
5.55 |
| 2026-04-15 00:00 |
02:16:56.75 |
-53:43:57.9 |
HIP 10650 |
5.67 |
| 2026-04-15 12:00 |
02:17:01.53 |
-53:43:39.5 |
HIP 10650 |
5.89 |
| 2026-04-16 00:00 |
02:17:06.31 |
-53:43:21.4 |
HIP 10650 |
6.19 |