| 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) |
| 2026-05-12 00:00 |
04:18:15.54 |
+24:34:05.8 |
HIP 20047 |
4.23 |
| 2026-05-12 12:00 |
04:18:18.20 |
+24:34:10.9 |
HIP 20047 |
4.82 |
| 2026-05-13 00:00 |
04:18:20.85 |
+24:34:15.9 |
HIP 20047 |
5.41 |
| 2026-05-13 12:00 |
04:18:23.52 |
+24:34:21.0 |
HIP 20047 |
6.01 |
| 2026-05-14 00:00 |
04:18:26.19 |
+24:34:26.2 |
HIP 20047 |
6.61 |
| 2026-05-14 12:00 |
04:18:28.86 |
+24:34:31.3 |
HIP 20047 |
7.22 |
| 2026-05-15 00:00 |
04:18:31.54 |
+24:34:36.5 |
HIP 20047 |
7.82 |
| 2026-05-15 12:00 |
04:18:34.22 |
+24:34:41.7 |
HIP 20047 |
8.43 |
| 2026-05-16 00:00 |
04:18:36.91 |
+24:34:46.9 |
HIP 20047 |
9.05 |
| 2026-05-16 12:00 |
04:18:39.60 |
+24:34:52.2 |
HIP 20047 |
9.66 |
| 2026-05-17 00:00 |
04:18:42.29 |
+24:34:57.4 |
HIP 20047 |
10.27 |
| 2026-05-17 12:00 |
04:18:44.99 |
+24:35:02.7 |
HIP 20047 |
10.89 |
| 2026-05-18 00:00 |
04:18:47.70 |
+24:35:08.1 |
HIP 20047 |
11.51 |
| 2026-05-18 12:00 |
04:18:50.40 |
+24:35:13.4 |
HIP 20047 |
12.12 |
| 2026-05-19 00:00 |
04:18:53.11 |
+24:35:18.8 |
HIP 20047 |
12.74 |
| 2026-05-19 12:00 |
04:18:55.83 |
+24:35:24.1 |
HIP 20047 |
13.36 |
| 2026-05-20 00:00 |
04:18:58.54 |
+24:35:29.5 |
HIP 20047 |
13.99 |
| 2026-05-20 12:00 |
04:19:01.26 |
+24:35:35.0 |
HIP 20047 |
14.61 |
| 2026-05-21 00:00 |
04:19:03.98 |
+24:35:40.4 |
HIP 20047 |
15.23 |
| 2026-05-21 12:00 |
04:19:06.71 |
+24:35:45.9 |
HIP 20047 |
15.86 |
| 2026-05-22 00:00 |
04:19:09.43 |
+24:35:51.4 |
HIP 20047 |
16.48 |
| 2026-05-22 12:00 |
04:19:12.16 |
+24:35:56.9 |
HIP 20047 |
17.10 |
| 2026-05-23 00:00 |
04:19:14.89 |
+24:36:02.4 |
HIP 20047 |
17.73 |
| 2026-05-23 12:00 |
04:19:17.62 |
+24:36:07.9 |
HIP 20047 |
18.36 |
| 2026-05-24 00:00 |
04:19:20.35 |
+24:36:13.5 |
HIP 20047 |
18.98 |
| 2026-05-24 12:00 |
04:19:23.08 |
+24:36:19.0 |
HIP 20047 |
19.61 |
| 2026-05-25 00:00 |
04:19:25.82 |
+24:36:24.6 |
HIP 20047 |
20.24 |
| 2026-05-25 12:00 |
04:19:28.56 |
+24:36:30.2 |
HIP 20047 |
20.86 |
| 2026-05-26 00:00 |
04:19:31.29 |
+24:36:35.8 |
HIP 20047 |
21.49 |
| 2026-05-26 12:00 |
04:19:34.03 |
+24:36:41.5 |
HIP 20047 |
22.12 |
| 2026-05-27 00:00 |
04:19:36.77 |
+24:36:47.1 |
HIP 20047 |
22.75 |
| 2026-05-27 12:00 |
04:19:39.50 |
+24:36:52.8 |
HIP 20047 |
23.38 |
| 2026-05-28 00:00 |
04:19:42.24 |
+24:36:58.5 |
HIP 20047 |
24.00 |
| 2026-05-28 12:00 |
04:19:44.98 |
+24:37:04.1 |
HIP 20047 |
24.63 |
| 2026-05-29 00:00 |
04:19:47.72 |
+24:37:09.8 |
HIP 20047 |
25.26 |
| 2026-05-29 12:00 |
04:19:50.46 |
+24:37:15.6 |
HIP 20047 |
25.89 |
| 2026-05-30 00:00 |
04:19:53.19 |
+24:37:21.3 |
HIP 20047 |
26.52 |
| 2026-05-30 12:00 |
04:19:55.93 |
+24:37:27.0 |
HIP 20047 |
27.15 |
| 2026-05-31 00:00 |
04:19:58.66 |
+24:37:32.8 |
HIP 20047 |
27.78 |
| 2026-05-31 12:00 |
04:20:01.40 |
+24:37:38.5 |
HIP 20047 |
28.40 |
| 2026-06-01 00:00 |
04:20:04.13 |
+24:37:44.3 |
HIP 20047 |
29.03 |
| 2026-06-01 12:00 |
04:20:06.86 |
+24:37:50.1 |
HIP 20047 |
29.66 |
| 2026-06-02 00:00 |
04:20:09.59 |
+24:37:55.9 |
HIP 20047 |
30.29 |