C/1999 L2 (LINEAR)

Metadata

Parameter Value
Designation C/1999 L2 (LINEAR)
Type C
Perihelion (tp_cal, UTC) 1999-08-04T21:14:58.248960Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:30:00Z
Obs used 94
NEO -
M1 13.000
K1 10.000
PC -
Osculating Elements
Parameter Value
Epoch (epoch_cal, TDB) 1999-06-22.0000000
e 0.99514569
q (au) 1.904764
a (au) 392.386280
i (deg) 43.941726
Ω (om, deg) 94.289819
ω (w, deg) 178.715840
M (ma, deg) 359.994435

Magnitude

C/1999 L2 (LINEAR) · Magnitude (Full range)

Scatter + Global Linear

$$ M_a = (11.743 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

Model Parameters

Parameter Value
H0 11.743
n 6.000
gf 1.000
gb -0.500
k 1.000
δ90 10.000
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)
2026-09-20 00:00 05:14:08.99 +06:56:33.3 HIP 24510 20.42
2026-09-20 12:00 05:14:08.69 +06:56:23.8 HIP 24510 20.54
2026-09-21 00:00 05:14:08.37 +06:56:14.4 HIP 24510 20.67
2026-09-21 12:00 05:14:08.02 +06:56:05.0 HIP 24510 20.80
2026-09-22 00:00 05:14:07.66 +06:55:55.5 HIP 24510 20.94
2026-09-22 12:00 05:14:07.27 +06:55:46.0 HIP 24510 21.09
2026-09-23 00:00 05:14:06.87 +06:55:36.6 HIP 24510 21.24
2026-09-23 12:00 05:14:06.44 +06:55:27.1 HIP 24510 21.40
2026-09-24 00:00 05:14:05.99 +06:55:17.6 HIP 24510 21.56
2026-09-24 12:00 05:14:05.53 +06:55:08.1 HIP 24510 21.72
2026-09-25 00:00 05:14:05.04 +06:54:58.5 HIP 24510 21.90
2026-09-25 12:00 05:14:04.53 +06:54:49.0 HIP 24510 22.07
2026-09-26 00:00 05:14:04.00 +06:54:39.5 HIP 24510 22.26
2026-09-26 12:00 05:14:03.45 +06:54:30.0 HIP 24510 22.45
2026-09-27 00:00 05:14:02.88 +06:54:20.4 HIP 24510 22.64
2026-09-27 12:00 05:14:02.28 +06:54:10.9 HIP 24510 22.84
2026-09-28 00:00 05:14:01.67 +06:54:01.3 HIP 24510 23.04
2026-09-28 12:00 05:14:01.04 +06:53:51.8 HIP 24510 23.25
2026-09-29 00:00 05:14:00.38 +06:53:42.2 HIP 24510 23.46
2026-09-29 12:00 05:13:59.71 +06:53:32.6 HIP 24510 23.68
2026-09-30 00:00 05:13:59.01 +06:53:23.1 HIP 24510 23.90
2026-09-30 12:00 05:13:58.30 +06:53:13.5 HIP 24510 24.13
2026-10-01 00:00 05:13:57.56 +06:53:04.0 HIP 24510 24.36
2026-10-01 12:00 05:13:56.81 +06:52:54.4 HIP 24510 24.60
2026-10-02 00:00 05:13:56.03 +06:52:44.9 HIP 24510 24.84
2026-10-02 12:00 05:13:55.23 +06:52:35.3 HIP 24510 25.09
2026-10-03 00:00 05:13:54.41 +06:52:25.8 HIP 24510 25.34
2026-10-03 12:00 05:13:53.58 +06:52:16.2 HIP 24510 25.60
2026-10-04 00:00 05:13:52.72 +06:52:06.7 HIP 24510 25.86
2026-10-04 12:00 05:13:51.84 +06:51:57.1 HIP 24229 25.83
2026-10-05 00:00 05:13:50.94 +06:51:47.6 HIP 24229 25.60
2026-10-05 12:00 05:13:50.02 +06:51:38.1 HIP 24229 25.37
2026-10-06 00:00 05:13:49.09 +06:51:28.6 HIP 24229 25.14
2026-10-06 12:00 05:13:48.13 +06:51:19.1 HIP 24229 24.90
2026-10-07 00:00 05:13:47.15 +06:51:09.6 HIP 24229 24.66
2026-10-07 12:00 05:13:46.15 +06:51:00.1 HIP 24229 24.42
2026-10-08 00:00 05:13:45.13 +06:50:50.6 HIP 24229 24.17
2026-10-08 12:00 05:13:44.10 +06:50:41.2 HIP 24229 23.92
2026-10-09 00:00 05:13:43.04 +06:50:31.7 HIP 24229 23.66
2026-10-09 12:00 05:13:41.96 +06:50:22.3 HIP 24229 23.40
2026-10-10 00:00 05:13:40.86 +06:50:12.9 HIP 24229 23.14
2026-10-10 12:00 05:13:39.75 +06:50:03.5 HIP 24229 22.87
2026-10-11 00:00 05:13:38.61 +06:49:54.1 HIP 24229 22.60