| 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
$$
M_a = (8.588 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.588 |
| n |
6.000 |
| gf |
0.802 |
| gb |
-0.776 |
| k |
1.000 |
| δ90 |
1.149 |
| 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 |
+9.5605 |
-1.777 |
| 1999-06-07 |
1999-07-27 |
+9.4771 |
-1.595 |
| 1999-07-27 |
1999-08-14 |
+2.1422 |
-0.125 |
| 1999-08-14 |
1999-09-20 |
-2.6607 |
+0.207 |
| 1999-09-20 |
1999-10-26 |
+1.7248 |
+0.241 |
| 1999-10-26 |
1999-11-16 |
-22.4608 |
+1.445 |
| 1999-11-16 |
2000-02-28 |
+1.5087 |
-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) |
| 2026-05-12 00:00 |
14:50:32.66 |
-52:07:41.7 |
HIP 72605 |
8.29 |
| 2026-05-12 12:00 |
14:50:28.90 |
-52:07:30.0 |
HIP 72605 |
8.60 |
| 2026-05-13 00:00 |
14:50:25.14 |
-52:07:18.1 |
HIP 72605 |
8.93 |
| 2026-05-13 12:00 |
14:50:21.39 |
-52:07:06.0 |
HIP 72605 |
9.30 |
| 2026-05-14 00:00 |
14:50:17.65 |
-52:06:53.7 |
HIP 72605 |
9.69 |
| 2026-05-14 12:00 |
14:50:13.91 |
-52:06:41.3 |
HIP 72605 |
10.11 |
| 2026-05-15 00:00 |
14:50:10.17 |
-52:06:28.6 |
HIP 72605 |
10.55 |
| 2026-05-15 12:00 |
14:50:06.44 |
-52:06:15.8 |
HIP 72605 |
11.01 |
| 2026-05-16 00:00 |
14:50:02.72 |
-52:06:02.8 |
HIP 72605 |
11.48 |
| 2026-05-16 12:00 |
14:49:59.00 |
-52:05:49.7 |
HIP 72605 |
11.97 |
| 2026-05-17 00:00 |
14:49:55.29 |
-52:05:36.4 |
HIP 72605 |
12.47 |
| 2026-05-17 12:00 |
14:49:51.59 |
-52:05:22.9 |
HIP 72605 |
12.98 |
| 2026-05-18 00:00 |
14:49:47.89 |
-52:05:09.2 |
HIP 72605 |
13.51 |
| 2026-05-18 12:00 |
14:49:44.20 |
-52:04:55.4 |
HIP 72605 |
14.04 |
| 2026-05-19 00:00 |
14:49:40.52 |
-52:04:41.4 |
HIP 72605 |
14.58 |
| 2026-05-19 12:00 |
14:49:36.85 |
-52:04:27.2 |
HIP 72605 |
15.12 |
| 2026-05-20 00:00 |
14:49:33.18 |
-52:04:12.9 |
HIP 72605 |
15.67 |
| 2026-05-20 12:00 |
14:49:29.53 |
-52:03:58.4 |
HIP 72605 |
16.23 |
| 2026-05-21 00:00 |
14:49:25.88 |
-52:03:43.7 |
HIP 72605 |
16.79 |
| 2026-05-21 12:00 |
14:49:22.24 |
-52:03:28.9 |
HIP 72605 |
17.36 |
| 2026-05-22 00:00 |
14:49:18.62 |
-52:03:13.9 |
HIP 72605 |
17.92 |
| 2026-05-22 12:00 |
14:49:15.00 |
-52:02:58.7 |
HIP 72605 |
18.50 |
| 2026-05-23 00:00 |
14:49:11.39 |
-52:02:43.4 |
HIP 72605 |
19.07 |
| 2026-05-23 12:00 |
14:49:07.79 |
-52:02:28.0 |
HIP 72605 |
19.65 |
| 2026-05-24 00:00 |
14:49:04.21 |
-52:02:12.4 |
HIP 72308 |
19.89 |
| 2026-05-24 12:00 |
14:49:00.63 |
-52:01:56.6 |
HIP 72308 |
19.56 |
| 2026-05-25 00:00 |
14:48:57.07 |
-52:01:40.7 |
HIP 72308 |
19.25 |
| 2026-05-25 12:00 |
14:48:53.52 |
-52:01:24.6 |
HIP 72308 |
18.95 |
| 2026-05-26 00:00 |
14:48:49.97 |
-52:01:08.4 |
HIP 72308 |
18.67 |
| 2026-05-26 12:00 |
14:48:46.45 |
-52:00:52.0 |
HIP 72308 |
18.40 |
| 2026-05-27 00:00 |
14:48:42.93 |
-52:00:35.5 |
HIP 72308 |
18.16 |
| 2026-05-27 12:00 |
14:48:39.42 |
-52:00:18.8 |
HIP 72308 |
17.94 |
| 2026-05-28 00:00 |
14:48:35.93 |
-52:00:02.0 |
HIP 72308 |
17.74 |
| 2026-05-28 12:00 |
14:48:32.45 |
-51:59:45.1 |
HIP 72308 |
17.56 |
| 2026-05-29 00:00 |
14:48:28.99 |
-51:59:28.0 |
HIP 72308 |
17.40 |
| 2026-05-29 12:00 |
14:48:25.54 |
-51:59:10.7 |
HIP 72308 |
17.26 |
| 2026-05-30 00:00 |
14:48:22.10 |
-51:58:53.3 |
HIP 72308 |
17.15 |
| 2026-05-30 12:00 |
14:48:18.68 |
-51:58:35.8 |
HIP 72308 |
17.06 |
| 2026-05-31 00:00 |
14:48:15.27 |
-51:58:18.2 |
HIP 72308 |
17.00 |
| 2026-05-31 12:00 |
14:48:11.87 |
-51:58:00.4 |
HIP 72308 |
16.96 |
| 2026-06-01 00:00 |
14:48:08.49 |
-51:57:42.5 |
HIP 72308 |
16.94 |
| 2026-06-01 12:00 |
14:48:05.12 |
-51:57:24.4 |
HIP 72308 |
16.95 |
| 2026-06-02 00:00 |
14:48:01.77 |
-51:57:06.2 |
HIP 72308 |
16.98 |