| Parameter |
Value |
| Designation |
C/2007 N3 (Lulin) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2009-01-10T15:21:20.111040Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:10Z |
| Obs used |
3853 |
| NEO |
- |
| M1 |
10.200 |
| K1 |
6.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2008-12-05.0000000 |
| e |
0.99998362 |
| q (au) |
1.212259 |
| a (au) |
74017.562220 |
| i (deg) |
178.373611 |
| Ω (om, deg) |
338.535163 |
| ω (w, deg) |
136.862191 |
| M (ma, deg) |
359.999998 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.207 + 3.193\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.207 |
| n |
3.193 |
| gf |
1.000 |
| gb |
-0.711 |
| k |
0.800 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2007-07-11 |
2007-11-01 |
+6.9416 |
-5.422 |
| 2007-11-01 |
2008-03-31 |
+15.1159 |
-11.353 |
| 2008-03-31 |
2008-08-20 |
-8.4186 |
+3.052 |
| 2008-08-20 |
2008-10-02 |
+13.2418 |
-5.726 |
| 2008-10-02 |
2009-01-10 |
+4.8131 |
-3.658 |
| 2009-01-10 |
2009-02-28 |
+40.2006 |
-6.492 |
| 2009-02-28 |
2011-01-01 |
+3.0849 |
-1.522 |
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 |
02:43:23.22 |
+14:20:15.7 |
HIP 12616 |
23.57 |
| 2026-05-12 12:00 |
02:43:26.15 |
+14:20:28.9 |
HIP 12616 |
23.95 |
| 2026-05-13 00:00 |
02:43:29.07 |
+14:20:42.2 |
HIP 12838 |
23.51 |
| 2026-05-13 12:00 |
02:43:31.99 |
+14:20:55.4 |
HIP 12838 |
22.90 |
| 2026-05-14 00:00 |
02:43:34.90 |
+14:21:08.6 |
HIP 12838 |
22.29 |
| 2026-05-14 12:00 |
02:43:37.81 |
+14:21:21.7 |
HIP 12838 |
21.69 |
| 2026-05-15 00:00 |
02:43:40.71 |
+14:21:34.8 |
HIP 12838 |
21.10 |
| 2026-05-15 12:00 |
02:43:43.61 |
+14:21:47.9 |
HIP 12838 |
20.53 |
| 2026-05-16 00:00 |
02:43:46.50 |
+14:22:00.9 |
HIP 12838 |
19.96 |
| 2026-05-16 12:00 |
02:43:49.39 |
+14:22:14.0 |
HIP 12838 |
19.40 |
| 2026-05-17 00:00 |
02:43:52.28 |
+14:22:26.9 |
HIP 12838 |
18.86 |
| 2026-05-17 12:00 |
02:43:55.16 |
+14:22:39.8 |
HIP 12838 |
18.33 |
| 2026-05-18 00:00 |
02:43:58.03 |
+14:22:52.7 |
HIP 12838 |
17.82 |
| 2026-05-18 12:00 |
02:44:00.89 |
+14:23:05.6 |
HIP 12838 |
17.32 |
| 2026-05-19 00:00 |
02:44:03.76 |
+14:23:18.4 |
HIP 12838 |
16.85 |
| 2026-05-19 12:00 |
02:44:06.61 |
+14:23:31.2 |
HIP 12838 |
16.39 |
| 2026-05-20 00:00 |
02:44:09.46 |
+14:23:43.9 |
HIP 12838 |
15.95 |
| 2026-05-20 12:00 |
02:44:12.30 |
+14:23:56.6 |
HIP 12838 |
15.53 |
| 2026-05-21 00:00 |
02:44:15.13 |
+14:24:09.2 |
HIP 12838 |
15.14 |
| 2026-05-21 12:00 |
02:44:17.96 |
+14:24:21.8 |
HIP 12838 |
14.77 |
| 2026-05-22 00:00 |
02:44:20.77 |
+14:24:34.3 |
HIP 12838 |
14.43 |
| 2026-05-22 12:00 |
02:44:23.59 |
+14:24:46.8 |
HIP 12838 |
14.11 |
| 2026-05-23 00:00 |
02:44:26.39 |
+14:24:59.3 |
HIP 12838 |
13.83 |
| 2026-05-23 12:00 |
02:44:29.18 |
+14:25:11.7 |
HIP 12838 |
13.58 |
| 2026-05-24 00:00 |
02:44:31.97 |
+14:25:24.0 |
HIP 12838 |
13.36 |
| 2026-05-24 12:00 |
02:44:34.75 |
+14:25:36.3 |
HIP 12838 |
13.18 |
| 2026-05-25 00:00 |
02:44:37.52 |
+14:25:48.5 |
HIP 12838 |
13.03 |
| 2026-05-25 12:00 |
02:44:40.28 |
+14:26:00.7 |
HIP 12838 |
12.92 |
| 2026-05-26 00:00 |
02:44:43.03 |
+14:26:12.9 |
HIP 12838 |
12.84 |
| 2026-05-26 12:00 |
02:44:45.77 |
+14:26:25.0 |
HIP 12838 |
12.81 |
| 2026-05-27 00:00 |
02:44:48.51 |
+14:26:37.0 |
HIP 12838 |
12.81 |
| 2026-05-27 12:00 |
02:44:51.23 |
+14:26:49.0 |
HIP 12838 |
12.85 |
| 2026-05-28 00:00 |
02:44:53.95 |
+14:27:00.9 |
HIP 12838 |
12.92 |
| 2026-05-28 12:00 |
02:44:56.65 |
+14:27:12.7 |
HIP 12838 |
13.03 |
| 2026-05-29 00:00 |
02:44:59.34 |
+14:27:24.6 |
HIP 12838 |
13.17 |
| 2026-05-29 12:00 |
02:45:02.03 |
+14:27:36.3 |
HIP 12838 |
13.35 |
| 2026-05-30 00:00 |
02:45:04.70 |
+14:27:48.0 |
HIP 12838 |
13.55 |
| 2026-05-30 12:00 |
02:45:07.37 |
+14:27:59.6 |
HIP 12838 |
13.79 |
| 2026-05-31 00:00 |
02:45:10.02 |
+14:28:11.2 |
HIP 12838 |
14.05 |
| 2026-05-31 12:00 |
02:45:12.66 |
+14:28:22.7 |
HIP 12838 |
14.34 |
| 2026-06-01 00:00 |
02:45:15.29 |
+14:28:34.2 |
HIP 12838 |
14.65 |
| 2026-06-01 12:00 |
02:45:17.91 |
+14:28:45.5 |
HIP 12838 |
14.98 |
| 2026-06-02 00:00 |
02:45:20.52 |
+14:28:56.9 |
HIP 12838 |
15.33 |