| 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) |
| 2026-05-12 00:00 |
02:21:17.62 |
-53:35:46.0 |
HIP 10797 |
29.02 |
| 2026-05-12 12:00 |
02:21:22.35 |
-53:35:46.7 |
HIP 10797 |
29.51 |
| 2026-05-13 00:00 |
02:21:27.08 |
-53:35:47.7 |
HIP 10797 |
30.00 |
| 2026-05-13 12:00 |
02:21:31.79 |
-53:35:49.1 |
HIP 10797 |
30.50 |
| 2026-05-14 00:00 |
02:21:36.49 |
-53:35:50.9 |
HIP 10797 |
31.00 |
| 2026-05-14 12:00 |
02:21:41.19 |
-53:35:53.0 |
HIP 11071 |
31.12 |
| 2026-05-15 00:00 |
02:21:45.87 |
-53:35:55.4 |
HIP 11071 |
31.00 |
| 2026-05-15 12:00 |
02:21:50.54 |
-53:35:58.3 |
HIP 11071 |
30.90 |
| 2026-05-16 00:00 |
02:21:55.21 |
-53:36:01.5 |
HIP 11071 |
30.82 |
| 2026-05-16 12:00 |
02:21:59.86 |
-53:36:05.0 |
HIP 11071 |
30.77 |
| 2026-05-17 00:00 |
02:22:04.50 |
-53:36:08.9 |
HIP 11071 |
30.74 |
| 2026-05-17 12:00 |
02:22:09.12 |
-53:36:13.2 |
HIP 11071 |
30.72 |
| 2026-05-18 00:00 |
02:22:13.73 |
-53:36:17.8 |
HIP 11071 |
30.74 |
| 2026-05-18 12:00 |
02:22:18.34 |
-53:36:22.7 |
HIP 11071 |
30.77 |
| 2026-05-19 00:00 |
02:22:22.92 |
-53:36:28.0 |
HIP 11071 |
30.82 |
| 2026-05-19 12:00 |
02:22:27.50 |
-53:36:33.7 |
HIP 11071 |
30.90 |
| 2026-05-20 00:00 |
02:22:32.06 |
-53:36:39.7 |
HIP 11203 |
30.85 |
| 2026-05-20 12:00 |
02:22:36.60 |
-53:36:46.1 |
HIP 11203 |
30.43 |
| 2026-05-21 00:00 |
02:22:41.14 |
-53:36:52.8 |
HIP 11203 |
30.01 |
| 2026-05-21 12:00 |
02:22:45.65 |
-53:37:00.0 |
HIP 11203 |
29.60 |
| 2026-05-22 00:00 |
02:22:50.15 |
-53:37:07.3 |
HIP 11203 |
29.20 |
| 2026-05-22 12:00 |
02:22:54.64 |
-53:37:15.1 |
HIP 11203 |
28.80 |
| 2026-05-23 00:00 |
02:22:59.11 |
-53:37:23.2 |
HIP 11203 |
28.41 |
| 2026-05-23 12:00 |
02:23:03.57 |
-53:37:31.7 |
HIP 11203 |
28.03 |
| 2026-05-24 00:00 |
02:23:08.01 |
-53:37:40.5 |
HIP 11203 |
27.65 |
| 2026-05-24 12:00 |
02:23:12.43 |
-53:37:49.7 |
HIP 11203 |
27.28 |
| 2026-05-25 00:00 |
02:23:16.84 |
-53:37:59.2 |
HIP 11203 |
26.91 |
| 2026-05-25 12:00 |
02:23:21.22 |
-53:38:09.0 |
HIP 11203 |
26.56 |
| 2026-05-26 00:00 |
02:23:25.60 |
-53:38:19.2 |
HIP 11203 |
26.21 |
| 2026-05-26 12:00 |
02:23:29.95 |
-53:38:29.7 |
HIP 11203 |
25.87 |
| 2026-05-27 00:00 |
02:23:34.29 |
-53:38:40.6 |
HIP 11203 |
25.53 |
| 2026-05-27 12:00 |
02:23:38.61 |
-53:38:51.8 |
HIP 11203 |
25.20 |
| 2026-05-28 00:00 |
02:23:42.91 |
-53:39:03.3 |
HIP 11203 |
24.89 |
| 2026-05-28 12:00 |
02:23:47.19 |
-53:39:15.2 |
HIP 11203 |
24.58 |
| 2026-05-29 00:00 |
02:23:51.45 |
-53:39:27.4 |
HIP 11203 |
24.28 |
| 2026-05-29 12:00 |
02:23:55.69 |
-53:39:39.9 |
HIP 11203 |
23.99 |
| 2026-05-30 00:00 |
02:23:59.92 |
-53:39:52.8 |
HIP 11203 |
23.71 |
| 2026-05-30 12:00 |
02:24:04.12 |
-53:40:06.0 |
HIP 11203 |
23.44 |
| 2026-05-31 00:00 |
02:24:08.31 |
-53:40:19.6 |
HIP 11203 |
23.17 |
| 2026-05-31 12:00 |
02:24:12.47 |
-53:40:33.4 |
HIP 11203 |
22.92 |
| 2026-06-01 00:00 |
02:24:16.62 |
-53:40:47.6 |
HIP 11203 |
22.68 |
| 2026-06-01 12:00 |
02:24:20.74 |
-53:41:02.2 |
HIP 11203 |
22.45 |
| 2026-06-02 00:00 |
02:24:24.85 |
-53:41:17.0 |
HIP 11203 |
22.24 |