| Parameter |
Value |
| Designation |
C/1999 J4 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1999-11-17T10:01:47.156160Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:00Z |
| Obs used |
40 |
| NEO |
- |
| M1 |
8.500 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1999-05-20.0000000 |
| e |
0.99971322 |
| q (au) |
3.781074 |
| a (au) |
13184.435879 |
| i (deg) |
118.909155 |
| Ω (om, deg) |
264.479748 |
| ω (w, deg) |
95.116153 |
| M (ma, deg) |
359.999882 |
Magnitude
Scatter + Global Linear
$$
M_a = (5.599 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
5.599 |
| n |
6.000 |
| gf |
0.997 |
| gb |
-0.998 |
| 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) |
| 2026-06-01 00:00 |
03:44:18.36 |
-31:56:10.3 |
HIP 17509 |
21.82 |
| 2026-06-01 12:00 |
03:44:21.08 |
-31:56:13.3 |
HIP 17509 |
21.64 |
| 2026-06-02 00:00 |
03:44:23.78 |
-31:56:16.5 |
HIP 17509 |
21.49 |
| 2026-06-02 12:00 |
03:44:26.49 |
-31:56:19.9 |
HIP 17509 |
21.36 |
| 2026-06-03 00:00 |
03:44:29.19 |
-31:56:23.6 |
HIP 17509 |
21.24 |
| 2026-06-03 12:00 |
03:44:31.88 |
-31:56:27.5 |
HIP 17509 |
21.15 |
| 2026-06-04 00:00 |
03:44:34.57 |
-31:56:31.7 |
HIP 17509 |
21.07 |
| 2026-06-04 12:00 |
03:44:37.25 |
-31:56:36.1 |
HIP 17509 |
21.02 |
| 2026-06-05 00:00 |
03:44:39.92 |
-31:56:40.8 |
HIP 17509 |
20.98 |
| 2026-06-05 12:00 |
03:44:42.59 |
-31:56:45.7 |
HIP 17509 |
20.96 |
| 2026-06-06 00:00 |
03:44:45.26 |
-31:56:50.9 |
HIP 17509 |
20.97 |
| 2026-06-06 12:00 |
03:44:47.91 |
-31:56:56.3 |
HIP 17509 |
20.99 |
| 2026-06-07 00:00 |
03:44:50.56 |
-31:57:02.0 |
HIP 17509 |
21.03 |
| 2026-06-07 12:00 |
03:44:53.20 |
-31:57:07.9 |
HIP 17509 |
21.10 |
| 2026-06-08 00:00 |
03:44:55.84 |
-31:57:14.1 |
HIP 17509 |
21.18 |
| 2026-06-08 12:00 |
03:44:58.47 |
-31:57:20.5 |
HIP 17509 |
21.28 |
| 2026-06-09 00:00 |
03:45:01.09 |
-31:57:27.1 |
HIP 17509 |
21.40 |
| 2026-06-09 12:00 |
03:45:03.70 |
-31:57:34.0 |
HIP 17509 |
21.54 |
| 2026-06-10 00:00 |
03:45:06.31 |
-31:57:41.2 |
HIP 17509 |
21.69 |
| 2026-06-10 12:00 |
03:45:08.90 |
-31:57:48.6 |
HIP 17509 |
21.87 |
| 2026-06-11 00:00 |
03:45:11.49 |
-31:57:56.2 |
HIP 17509 |
22.06 |
| 2026-06-11 12:00 |
03:45:14.07 |
-31:58:04.1 |
HIP 17509 |
22.27 |
| 2026-06-12 00:00 |
03:45:16.64 |
-31:58:12.2 |
HIP 17509 |
22.49 |
| 2026-06-12 12:00 |
03:45:19.21 |
-31:58:20.6 |
HIP 17630 |
22.32 |
| 2026-06-13 00:00 |
03:45:21.76 |
-31:58:29.2 |
HIP 17630 |
21.81 |
| 2026-06-13 12:00 |
03:45:24.31 |
-31:58:38.1 |
HIP 17630 |
21.31 |
| 2026-06-14 00:00 |
03:45:26.84 |
-31:58:47.2 |
HIP 17630 |
20.81 |
| 2026-06-14 12:00 |
03:45:29.37 |
-31:58:56.5 |
HIP 17630 |
20.30 |
| 2026-06-15 00:00 |
03:45:31.89 |
-31:59:06.1 |
HIP 17630 |
19.81 |
| 2026-06-15 12:00 |
03:45:34.39 |
-31:59:15.9 |
HIP 17630 |
19.31 |
| 2026-06-16 00:00 |
03:45:36.89 |
-31:59:26.0 |
HIP 17630 |
18.81 |
| 2026-06-16 12:00 |
03:45:39.38 |
-31:59:36.3 |
HIP 17630 |
18.32 |
| 2026-06-17 00:00 |
03:45:41.85 |
-31:59:46.9 |
HIP 17630 |
17.83 |
| 2026-06-17 12:00 |
03:45:44.32 |
-31:59:57.7 |
HIP 17630 |
17.34 |
| 2026-06-18 00:00 |
03:45:46.77 |
-32:00:08.7 |
HIP 17630 |
16.85 |
| 2026-06-18 12:00 |
03:45:49.21 |
-32:00:20.0 |
HIP 17630 |
16.37 |
| 2026-06-19 00:00 |
03:45:51.65 |
-32:00:31.5 |
HIP 17630 |
15.89 |
| 2026-06-19 12:00 |
03:45:54.07 |
-32:00:43.3 |
HIP 17630 |
15.41 |
| 2026-06-20 00:00 |
03:45:56.47 |
-32:00:55.3 |
HIP 17630 |
14.94 |
| 2026-06-20 12:00 |
03:45:58.87 |
-32:01:07.5 |
HIP 17630 |
14.47 |
| 2026-06-21 00:00 |
03:46:01.26 |
-32:01:20.0 |
HIP 17630 |
14.00 |
| 2026-06-21 12:00 |
03:46:03.63 |
-32:01:32.7 |
HIP 17630 |
13.54 |
| 2026-06-22 00:00 |
03:46:05.99 |
-32:01:45.6 |
HIP 17630 |
13.08 |