| Parameter |
Value |
| Designation |
C/1998 M1 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1998-10-28T02:41:20.860800Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:53Z |
| Obs used |
191 |
| NEO |
- |
| M1 |
6.500 |
| K1 |
14.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1998-09-21.0000000 |
| e |
0.99276578 |
| q (au) |
3.118124 |
| a (au) |
431.024098 |
| i (deg) |
20.384564 |
| Ω (om, deg) |
256.067464 |
| ω (w, deg) |
19.403420 |
| M (ma, deg) |
359.995912 |
Magnitude
Scatter + Global Linear
$$
M_a = (5.198 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
5.198 |
| n |
6.000 |
| gf |
0.986 |
| gb |
-0.501 |
| k |
1.000 |
| δ90 |
9.999 |
| 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 |
04:14:53.66 |
+24:29:02.1 |
HIP 19829 |
10.81 |
| 2026-03-26 12:00 |
04:14:55.10 |
+24:29:03.1 |
HIP 19829 |
10.75 |
| 2026-03-27 00:00 |
04:14:56.55 |
+24:29:04.1 |
HIP 19829 |
10.69 |
| 2026-03-27 12:00 |
04:14:58.03 |
+24:29:05.2 |
HIP 19829 |
10.64 |
| 2026-03-28 00:00 |
04:14:59.52 |
+24:29:06.4 |
HIP 19829 |
10.61 |
| 2026-03-28 12:00 |
04:15:01.03 |
+24:29:07.6 |
HIP 19829 |
10.58 |
| 2026-03-29 00:00 |
04:15:02.56 |
+24:29:08.9 |
HIP 19829 |
10.57 |
| 2026-03-29 12:00 |
04:15:04.11 |
+24:29:10.2 |
HIP 19829 |
10.57 |
| 2026-03-30 00:00 |
04:15:05.68 |
+24:29:11.5 |
HIP 19829 |
10.58 |
| 2026-03-30 12:00 |
04:15:07.27 |
+24:29:13.0 |
HIP 19829 |
10.61 |
| 2026-03-31 00:00 |
04:15:08.87 |
+24:29:14.4 |
HIP 19829 |
10.65 |
| 2026-03-31 12:00 |
04:15:10.49 |
+24:29:16.0 |
HIP 19829 |
10.70 |
| 2026-04-01 00:00 |
04:15:12.13 |
+24:29:17.6 |
HIP 19829 |
10.76 |
| 2026-04-01 12:00 |
04:15:13.79 |
+24:29:19.2 |
HIP 19829 |
10.84 |
| 2026-04-02 00:00 |
04:15:15.47 |
+24:29:20.9 |
HIP 19829 |
10.94 |
| 2026-04-02 12:00 |
04:15:17.17 |
+24:29:22.7 |
HIP 19829 |
11.05 |
| 2026-04-03 00:00 |
04:15:18.88 |
+24:29:24.5 |
HIP 19829 |
11.17 |
| 2026-04-03 12:00 |
04:15:20.61 |
+24:29:26.3 |
HIP 19829 |
11.31 |
| 2026-04-04 00:00 |
04:15:22.36 |
+24:29:28.2 |
HIP 19829 |
11.46 |
| 2026-04-04 12:00 |
04:15:24.12 |
+24:29:30.2 |
HIP 19829 |
11.62 |
| 2026-04-05 00:00 |
04:15:25.91 |
+24:29:32.2 |
HIP 19829 |
11.80 |
| 2026-04-05 12:00 |
04:15:27.70 |
+24:29:34.3 |
HIP 19829 |
12.00 |
| 2026-04-06 00:00 |
04:15:29.52 |
+24:29:36.4 |
HIP 19829 |
12.20 |
| 2026-04-06 12:00 |
04:15:31.35 |
+24:29:38.6 |
HIP 19829 |
12.42 |
| 2026-04-07 00:00 |
04:15:33.20 |
+24:29:40.8 |
HIP 19829 |
12.65 |
| 2026-04-07 12:00 |
04:15:35.07 |
+24:29:43.1 |
HIP 19829 |
12.89 |
| 2026-04-08 00:00 |
04:15:36.95 |
+24:29:45.4 |
HIP 19829 |
13.15 |
| 2026-04-08 12:00 |
04:15:38.85 |
+24:29:47.8 |
HIP 19829 |
13.42 |
| 2026-04-09 00:00 |
04:15:40.77 |
+24:29:50.2 |
HIP 19829 |
13.70 |
| 2026-04-09 12:00 |
04:15:42.70 |
+24:29:52.7 |
HIP 19829 |
13.99 |
| 2026-04-10 00:00 |
04:15:44.65 |
+24:29:55.2 |
HIP 19829 |
14.29 |
| 2026-04-10 12:00 |
04:15:46.61 |
+24:29:57.8 |
HIP 19829 |
14.60 |
| 2026-04-11 00:00 |
04:15:48.59 |
+24:30:00.4 |
HIP 19829 |
14.92 |
| 2026-04-11 12:00 |
04:15:50.59 |
+24:30:03.1 |
HIP 19829 |
15.25 |
| 2026-04-12 00:00 |
04:15:52.60 |
+24:30:05.8 |
HIP 19829 |
15.59 |
| 2026-04-12 12:00 |
04:15:54.62 |
+24:30:08.6 |
HIP 19829 |
15.94 |
| 2026-04-13 00:00 |
04:15:56.67 |
+24:30:11.4 |
HIP 19829 |
16.30 |
| 2026-04-13 12:00 |
04:15:58.72 |
+24:30:14.3 |
HIP 19829 |
16.66 |
| 2026-04-14 00:00 |
04:16:00.79 |
+24:30:17.2 |
HIP 19829 |
17.04 |
| 2026-04-14 12:00 |
04:16:02.88 |
+24:30:20.1 |
HIP 19829 |
17.42 |
| 2026-04-15 00:00 |
04:16:04.98 |
+24:30:23.1 |
HIP 19829 |
17.81 |
| 2026-04-15 12:00 |
04:16:07.09 |
+24:30:26.2 |
HIP 19829 |
18.20 |
| 2026-04-16 00:00 |
04:16:09.22 |
+24:30:29.3 |
HIP 19829 |
18.61 |