| Parameter |
Value |
| Designation |
C/1999 J3 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1999-09-20T04:00:17.066880Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:59Z |
| Obs used |
187 |
| NEO |
- |
| M1 |
11.300 |
| K1 |
13.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1999-09-08.0000000 |
| e |
0.99938639 |
| q (au) |
0.976809 |
| a (au) |
1591.905151 |
| i (deg) |
101.656036 |
| Ω (om, deg) |
228.978961 |
| ω (w, deg) |
161.980562 |
| M (ma, deg) |
359.999811 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.592 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.592 |
| n |
6.000 |
| gf |
0.800 |
| gb |
-0.502 |
| k |
1.000 |
| δ90 |
1.121 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 1999-05-12 |
1999-06-07 |
+9.5620 |
-1.775 |
| 1999-06-07 |
1999-07-27 |
+9.4778 |
-1.593 |
| 1999-07-27 |
1999-08-14 |
+2.1427 |
-0.123 |
| 1999-08-14 |
1999-09-20 |
-2.6402 |
+0.207 |
| 1999-09-20 |
1999-10-26 |
+1.7372 |
+0.240 |
| 1999-10-26 |
1999-11-16 |
-22.4430 |
+1.444 |
| 1999-11-16 |
2000-02-28 |
+1.5136 |
-1.953 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
14:44:09.03 |
-51:14:48.1 |
HIP 72072 |
4.85 |
| 2026-07-29 12:00 |
14:44:08.60 |
-51:14:25.5 |
HIP 72072 |
4.65 |
| 2026-07-30 00:00 |
14:44:08.20 |
-51:14:02.9 |
HIP 72072 |
4.47 |
| 2026-07-30 12:00 |
14:44:07.82 |
-51:13:40.5 |
HIP 72072 |
4.31 |
| 2026-07-31 00:00 |
14:44:07.48 |
-51:13:18.0 |
HIP 72072 |
4.18 |
| 2026-07-31 12:00 |
14:44:07.17 |
-51:12:55.7 |
HIP 72072 |
4.07 |
| 2026-08-01 00:00 |
14:44:06.89 |
-51:12:33.4 |
HIP 72072 |
3.99 |
| 2026-08-01 12:00 |
14:44:06.64 |
-51:12:11.2 |
HIP 72072 |
3.95 |
| 2026-08-02 00:00 |
14:44:06.43 |
-51:11:49.0 |
HIP 72072 |
3.93 |
| 2026-08-02 12:00 |
14:44:06.24 |
-51:11:26.9 |
HIP 72072 |
3.94 |
| 2026-08-03 00:00 |
14:44:06.08 |
-51:11:04.9 |
HIP 72072 |
3.98 |
| 2026-08-03 12:00 |
14:44:05.95 |
-51:10:42.9 |
HIP 72072 |
4.05 |
| 2026-08-04 00:00 |
14:44:05.86 |
-51:10:21.1 |
HIP 72072 |
4.15 |
| 2026-08-04 12:00 |
14:44:05.79 |
-51:09:59.3 |
HIP 72072 |
4.27 |
| 2026-08-05 00:00 |
14:44:05.76 |
-51:09:37.5 |
HIP 72072 |
4.41 |
| 2026-08-05 12:00 |
14:44:05.75 |
-51:09:15.9 |
HIP 72072 |
4.57 |
| 2026-08-06 00:00 |
14:44:05.78 |
-51:08:54.3 |
HIP 72072 |
4.75 |
| 2026-08-06 12:00 |
14:44:05.83 |
-51:08:32.8 |
HIP 72072 |
4.94 |
| 2026-08-07 00:00 |
14:44:05.92 |
-51:08:11.4 |
HIP 72072 |
5.15 |
| 2026-08-07 12:00 |
14:44:06.04 |
-51:07:50.1 |
HIP 72072 |
5.37 |
| 2026-08-08 00:00 |
14:44:06.19 |
-51:07:28.8 |
HIP 72072 |
5.59 |
| 2026-08-08 12:00 |
14:44:06.37 |
-51:07:07.7 |
HIP 72072 |
5.83 |
| 2026-08-09 00:00 |
14:44:06.58 |
-51:06:46.6 |
HIP 72072 |
6.07 |
| 2026-08-09 12:00 |
14:44:06.82 |
-51:06:25.6 |
HIP 72072 |
6.32 |
| 2026-08-10 00:00 |
14:44:07.09 |
-51:06:04.7 |
HIP 72072 |
6.58 |
| 2026-08-10 12:00 |
14:44:07.39 |
-51:05:43.9 |
HIP 72072 |
6.84 |
| 2026-08-11 00:00 |
14:44:07.72 |
-51:05:23.2 |
HIP 72072 |
7.10 |
| 2026-08-11 12:00 |
14:44:08.08 |
-51:05:02.6 |
HIP 72072 |
7.37 |
| 2026-08-12 00:00 |
14:44:08.48 |
-51:04:42.1 |
HIP 72072 |
7.64 |
| 2026-08-12 12:00 |
14:44:08.90 |
-51:04:21.7 |
HIP 72072 |
7.91 |
| 2026-08-13 00:00 |
14:44:09.35 |
-51:04:01.4 |
HIP 72072 |
8.18 |
| 2026-08-13 12:00 |
14:44:09.84 |
-51:03:41.1 |
HIP 72072 |
8.46 |
| 2026-08-14 00:00 |
14:44:10.35 |
-51:03:21.0 |
HIP 72072 |
8.74 |
| 2026-08-14 12:00 |
14:44:10.89 |
-51:03:01.0 |
HIP 72072 |
9.02 |
| 2026-08-15 00:00 |
14:44:11.47 |
-51:02:41.1 |
HIP 72072 |
9.30 |
| 2026-08-15 12:00 |
14:44:12.07 |
-51:02:21.3 |
HIP 72072 |
9.58 |
| 2026-08-16 00:00 |
14:44:12.71 |
-51:02:01.6 |
HIP 72072 |
9.86 |
| 2026-08-16 12:00 |
14:44:13.37 |
-51:01:42.0 |
HIP 72072 |
10.14 |
| 2026-08-17 00:00 |
14:44:14.06 |
-51:01:22.6 |
HIP 72072 |
10.43 |
| 2026-08-17 12:00 |
14:44:14.79 |
-51:01:03.2 |
HIP 72072 |
10.71 |
| 2026-08-18 00:00 |
14:44:15.54 |
-51:00:43.9 |
HIP 72072 |
10.99 |
| 2026-08-18 12:00 |
14:44:16.32 |
-51:00:24.8 |
HIP 72072 |
11.28 |
| 2026-08-19 00:00 |
14:44:17.13 |
-51:00:05.8 |
HIP 72072 |
11.56 |