| Parameter |
Value |
| Designation |
C/1998 Q1 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1998-06-29T12:12:45.789120Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:57Z |
| Obs used |
147 |
| NEO |
- |
| M1 |
14.000 |
| K1 |
10.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1998-09-07.0000000 |
| e |
0.99559540 |
| q (au) |
1.577877 |
| a (au) |
358.233578 |
| i (deg) |
32.305811 |
| Ω (om, deg) |
159.784650 |
| ω (w, deg) |
134.732300 |
| M (ma, deg) |
0.010101 |
Magnitude
Scatter + Global Linear
$$
M_a = (16.842 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
16.842 |
| n |
2.000 |
| gf |
0.998 |
| gb |
-0.819 |
| k |
0.987 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
06:26:28.92 |
-05:16:00.0 |
HIP 30761 |
21.47 |
| 2026-05-12 12:00 |
06:26:30.67 |
-05:15:48.7 |
HIP 30761 |
21.00 |
| 2026-05-13 00:00 |
06:26:32.43 |
-05:15:37.5 |
HIP 30761 |
20.52 |
| 2026-05-13 12:00 |
06:26:34.20 |
-05:15:26.4 |
HIP 30761 |
20.05 |
| 2026-05-14 00:00 |
06:26:35.99 |
-05:15:15.4 |
HIP 30761 |
19.57 |
| 2026-05-14 12:00 |
06:26:37.79 |
-05:15:04.5 |
HIP 30761 |
19.08 |
| 2026-05-15 00:00 |
06:26:39.61 |
-05:14:53.8 |
HIP 30761 |
18.60 |
| 2026-05-15 12:00 |
06:26:41.43 |
-05:14:43.2 |
HIP 30761 |
18.11 |
| 2026-05-16 00:00 |
06:26:43.27 |
-05:14:32.6 |
HIP 30761 |
17.62 |
| 2026-05-16 12:00 |
06:26:45.13 |
-05:14:22.3 |
HIP 30761 |
17.13 |
| 2026-05-17 00:00 |
06:26:46.99 |
-05:14:12.0 |
HIP 30761 |
16.64 |
| 2026-05-17 12:00 |
06:26:48.87 |
-05:14:01.8 |
HIP 30761 |
16.14 |
| 2026-05-18 00:00 |
06:26:50.76 |
-05:13:51.8 |
HIP 30761 |
15.64 |
| 2026-05-18 12:00 |
06:26:52.67 |
-05:13:41.9 |
HIP 30761 |
15.14 |
| 2026-05-19 00:00 |
06:26:54.58 |
-05:13:32.1 |
HIP 30761 |
14.64 |
| 2026-05-19 12:00 |
06:26:56.51 |
-05:13:22.4 |
HIP 30761 |
14.13 |
| 2026-05-20 00:00 |
06:26:58.45 |
-05:13:12.9 |
HIP 30761 |
13.62 |
| 2026-05-20 12:00 |
06:27:00.40 |
-05:13:03.5 |
HIP 30761 |
13.11 |
| 2026-05-21 00:00 |
06:27:02.37 |
-05:12:54.2 |
HIP 30761 |
12.60 |
| 2026-05-21 12:00 |
06:27:04.34 |
-05:12:45.0 |
HIP 30761 |
12.08 |
| 2026-05-22 00:00 |
06:27:06.33 |
-05:12:36.0 |
HIP 30761 |
11.57 |
| 2026-05-22 12:00 |
06:27:08.32 |
-05:12:27.0 |
HIP 30761 |
11.05 |
| 2026-05-23 00:00 |
06:27:10.33 |
-05:12:18.2 |
HIP 30761 |
10.53 |
| 2026-05-23 12:00 |
06:27:12.35 |
-05:12:09.6 |
HIP 30761 |
10.00 |
| 2026-05-24 00:00 |
06:27:14.38 |
-05:12:01.0 |
HIP 30761 |
9.48 |
| 2026-05-24 12:00 |
06:27:16.42 |
-05:11:52.6 |
HIP 30761 |
8.95 |
| 2026-05-25 00:00 |
06:27:18.47 |
-05:11:44.4 |
HIP 30761 |
8.42 |
| 2026-05-25 12:00 |
06:27:20.53 |
-05:11:36.2 |
HIP 30761 |
7.89 |
| 2026-05-26 00:00 |
06:27:22.60 |
-05:11:28.2 |
HIP 30761 |
7.36 |
| 2026-05-26 12:00 |
06:27:24.68 |
-05:11:20.3 |
HIP 30761 |
6.83 |
| 2026-05-27 00:00 |
06:27:26.77 |
-05:11:12.5 |
HIP 30761 |
6.29 |
| 2026-05-27 12:00 |
06:27:28.87 |
-05:11:04.9 |
HIP 30761 |
5.76 |
| 2026-05-28 00:00 |
06:27:30.98 |
-05:10:57.4 |
HIP 30761 |
5.22 |
| 2026-05-28 12:00 |
06:27:33.09 |
-05:10:50.0 |
HIP 30761 |
4.68 |
| 2026-05-29 00:00 |
06:27:35.22 |
-05:10:42.7 |
HIP 30761 |
4.14 |
| 2026-05-29 12:00 |
06:27:37.36 |
-05:10:35.6 |
HIP 30761 |
3.60 |
| 2026-05-30 00:00 |
06:27:39.51 |
-05:10:28.6 |
HIP 30761 |
3.06 |
| 2026-05-30 12:00 |
06:27:41.66 |
-05:10:21.8 |
HIP 30761 |
2.52 |
| 2026-05-31 00:00 |
06:27:43.82 |
-05:10:15.1 |
HIP 30761 |
1.99 |
| 2026-05-31 12:00 |
06:27:46.00 |
-05:10:08.5 |
HIP 30761 |
1.48 |
| 2026-06-01 00:00 |
06:27:48.18 |
-05:10:02.0 |
HIP 30761 |
1.00 |
| 2026-06-01 12:00 |
06:27:50.36 |
-05:09:55.7 |
HIP 30761 |
0.65 |
| 2026-06-02 00:00 |
06:27:52.56 |
-05:09:49.5 |
HIP 30761 |
0.68 |