C/1998 Q1 (LINEAR)
| 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) |
| 2026-02-03 00:00 |
06:26:42.81 |
-06:08:09.2 |
HIP 30607 |
11.75 |
| 2026-02-03 12:00 |
06:26:40.91 |
-06:07:56.4 |
HIP 30607 |
11.39 |
| 2026-02-04 00:00 |
06:26:39.03 |
-06:07:43.6 |
HIP 30607 |
11.05 |
| 2026-02-04 12:00 |
06:26:37.15 |
-06:07:30.7 |
HIP 30607 |
10.72 |
| 2026-02-05 00:00 |
06:26:35.30 |
-06:07:17.6 |
HIP 30607 |
10.41 |
| 2026-02-05 12:00 |
06:26:33.45 |
-06:07:04.4 |
HIP 30607 |
10.13 |
| 2026-02-06 00:00 |
06:26:31.63 |
-06:06:51.2 |
HIP 30607 |
9.86 |
| 2026-02-06 12:00 |
06:26:29.81 |
-06:06:37.8 |
HIP 30607 |
9.62 |
| 2026-02-07 00:00 |
06:26:28.01 |
-06:06:24.3 |
HIP 30607 |
9.40 |
| 2026-02-07 12:00 |
06:26:26.23 |
-06:06:10.7 |
HIP 30607 |
9.21 |
| 2026-02-08 00:00 |
06:26:24.46 |
-06:05:56.9 |
HIP 30607 |
9.04 |
| 2026-02-08 12:00 |
06:26:22.71 |
-06:05:43.1 |
HIP 30607 |
8.91 |
| 2026-02-09 00:00 |
06:26:20.97 |
-06:05:29.2 |
HIP 30607 |
8.80 |
| 2026-02-09 12:00 |
06:26:19.25 |
-06:05:15.2 |
HIP 30607 |
8.73 |
| 2026-02-10 00:00 |
06:26:17.54 |
-06:05:01.0 |
HIP 30607 |
8.68 |
| 2026-02-10 12:00 |
06:26:15.85 |
-06:04:46.8 |
HIP 30607 |
8.66 |
| 2026-02-11 00:00 |
06:26:14.17 |
-06:04:32.5 |
HIP 30607 |
8.68 |
| 2026-02-11 12:00 |
06:26:12.51 |
-06:04:18.0 |
HIP 30607 |
8.72 |
| 2026-02-12 00:00 |
06:26:10.87 |
-06:04:03.5 |
HIP 30607 |
8.80 |
| 2026-02-12 12:00 |
06:26:09.25 |
-06:03:48.9 |
HIP 30607 |
8.90 |
| 2026-02-13 00:00 |
06:26:07.64 |
-06:03:34.2 |
HIP 30607 |
9.02 |
| 2026-02-13 12:00 |
06:26:06.04 |
-06:03:19.3 |
HIP 30607 |
9.17 |
| 2026-02-14 00:00 |
06:26:04.47 |
-06:03:04.4 |
HIP 30607 |
9.35 |
| 2026-02-14 12:00 |
06:26:02.91 |
-06:02:49.4 |
HIP 30607 |
9.54 |
| 2026-02-15 00:00 |
06:26:01.36 |
-06:02:34.3 |
HIP 30607 |
9.76 |
| 2026-02-15 12:00 |
06:25:59.84 |
-06:02:19.2 |
HIP 30607 |
9.99 |
| 2026-02-16 00:00 |
06:25:58.33 |
-06:02:03.9 |
HIP 30607 |
10.24 |
| 2026-02-16 12:00 |
06:25:56.84 |
-06:01:48.5 |
HIP 30607 |
10.51 |
| 2026-02-17 00:00 |
06:25:55.37 |
-06:01:33.1 |
HIP 30607 |
10.78 |
| 2026-02-17 12:00 |
06:25:53.91 |
-06:01:17.6 |
HIP 30607 |
11.07 |
| 2026-02-18 00:00 |
06:25:52.48 |
-06:01:02.0 |
HIP 30607 |
11.38 |
| 2026-02-18 12:00 |
06:25:51.06 |
-06:00:46.3 |
HIP 30607 |
11.69 |
| 2026-02-19 00:00 |
06:25:49.66 |
-06:00:30.5 |
HIP 30607 |
12.00 |
| 2026-02-19 12:00 |
06:25:48.27 |
-06:00:14.7 |
HIP 30607 |
12.33 |
| 2026-02-20 00:00 |
06:25:46.91 |
-05:59:58.7 |
HIP 30607 |
12.66 |
| 2026-02-20 12:00 |
06:25:45.56 |
-05:59:42.7 |
HIP 30535 |
12.80 |
| 2026-02-21 00:00 |
06:25:44.23 |
-05:59:26.7 |
HIP 30535 |
12.37 |
| 2026-02-21 12:00 |
06:25:42.92 |
-05:59:10.5 |
HIP 30535 |
11.95 |
| 2026-02-22 00:00 |
06:25:41.63 |
-05:58:54.3 |
HIP 30535 |
11.53 |
| 2026-02-22 12:00 |
06:25:40.36 |
-05:58:38.0 |
HIP 30535 |
11.12 |
| 2026-02-23 00:00 |
06:25:39.11 |
-05:58:21.7 |
HIP 30535 |
10.70 |
| 2026-02-23 12:00 |
06:25:37.87 |
-05:58:05.3 |
HIP 30535 |
10.29 |
| 2026-02-24 00:00 |
06:25:36.66 |
-05:57:48.8 |
HIP 30535 |
9.88 |