| Parameter |
Value |
| Designation |
C/2007 F1 (LONEOS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2007-10-28T18:14:50.939520Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:06Z |
| Obs used |
197 |
| NEO |
- |
| M1 |
10.800 |
| K1 |
11.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2007-06-09.0000000 |
| e |
1.00008815 |
| q (au) |
0.402375 |
| a (au) |
-4564.775911 |
| i (deg) |
116.082089 |
| Ω (om, deg) |
172.886668 |
| ω (w, deg) |
153.710777 |
| M (ma, deg) |
-0.000453 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.307 + 5.138\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.307 |
| n |
5.138 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
0.800 |
| δ90 |
1.000 |
| 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 |
| 2007-03-19 |
2007-07-21 |
-2.6597 |
+1.473 |
| 2007-07-21 |
2007-10-03 |
+5.6634 |
-0.925 |
| 2007-10-03 |
2007-10-08 |
-17.3460 |
-3.750 |
| 2007-10-08 |
2007-10-16 |
-8.7273 |
-2.562 |
| 2007-10-16 |
2007-10-20 |
-2.9495 |
-0.609 |
| 2007-10-20 |
2007-10-28 |
-22.4473 |
-7.211 |
| 2007-11-03 |
2007-12-02 |
-8.8732 |
-1.511 |
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 |
11:36:47.38 |
-35:09:46.6 |
HIP 56560 |
19.37 |
| 2026-05-12 12:00 |
11:36:45.51 |
-35:09:14.3 |
HIP 56560 |
19.54 |
| 2026-05-13 00:00 |
11:36:43.67 |
-35:08:41.9 |
HIP 56560 |
19.74 |
| 2026-05-13 12:00 |
11:36:41.85 |
-35:08:09.5 |
HIP 56560 |
19.96 |
| 2026-05-14 00:00 |
11:36:40.06 |
-35:07:37.1 |
HIP 56560 |
20.21 |
| 2026-05-14 12:00 |
11:36:38.30 |
-35:07:04.7 |
HIP 56560 |
20.47 |
| 2026-05-15 00:00 |
11:36:36.56 |
-35:06:32.3 |
HIP 56560 |
20.76 |
| 2026-05-15 12:00 |
11:36:34.85 |
-35:05:59.8 |
HIP 56560 |
21.06 |
| 2026-05-16 00:00 |
11:36:33.16 |
-35:05:27.4 |
HIP 56567 |
20.45 |
| 2026-05-16 12:00 |
11:36:31.50 |
-35:04:55.0 |
HIP 56567 |
19.81 |
| 2026-05-17 00:00 |
11:36:29.87 |
-35:04:22.6 |
HIP 56567 |
19.18 |
| 2026-05-17 12:00 |
11:36:28.27 |
-35:03:50.2 |
HIP 56567 |
18.55 |
| 2026-05-18 00:00 |
11:36:26.69 |
-35:03:17.8 |
HIP 56567 |
17.92 |
| 2026-05-18 12:00 |
11:36:25.14 |
-35:02:45.4 |
HIP 56567 |
17.30 |
| 2026-05-19 00:00 |
11:36:23.61 |
-35:02:13.0 |
HIP 56567 |
16.68 |
| 2026-05-19 12:00 |
11:36:22.11 |
-35:01:40.7 |
HIP 56567 |
16.06 |
| 2026-05-20 00:00 |
11:36:20.64 |
-35:01:08.3 |
HIP 56567 |
15.44 |
| 2026-05-20 12:00 |
11:36:19.20 |
-35:00:36.0 |
HIP 56567 |
14.83 |
| 2026-05-21 00:00 |
11:36:17.79 |
-35:00:03.7 |
HIP 56567 |
14.22 |
| 2026-05-21 12:00 |
11:36:16.40 |
-34:59:31.5 |
HIP 56567 |
13.61 |
| 2026-05-22 00:00 |
11:36:15.04 |
-34:58:59.3 |
HIP 56567 |
13.01 |
| 2026-05-22 12:00 |
11:36:13.70 |
-34:58:27.1 |
HIP 56567 |
12.41 |
| 2026-05-23 00:00 |
11:36:12.40 |
-34:57:54.9 |
HIP 56567 |
11.81 |
| 2026-05-23 12:00 |
11:36:11.12 |
-34:57:22.8 |
HIP 56567 |
11.21 |
| 2026-05-24 00:00 |
11:36:09.87 |
-34:56:50.7 |
HIP 56567 |
10.62 |
| 2026-05-24 12:00 |
11:36:08.65 |
-34:56:18.7 |
HIP 56567 |
10.03 |
| 2026-05-25 00:00 |
11:36:07.46 |
-34:55:46.7 |
HIP 56567 |
9.44 |
| 2026-05-25 12:00 |
11:36:06.29 |
-34:55:14.7 |
HIP 56567 |
8.86 |
| 2026-05-26 00:00 |
11:36:05.15 |
-34:54:42.8 |
HIP 56567 |
8.28 |
| 2026-05-26 12:00 |
11:36:04.04 |
-34:54:11.0 |
HIP 56567 |
7.70 |
| 2026-05-27 00:00 |
11:36:02.96 |
-34:53:39.2 |
HIP 56567 |
7.13 |
| 2026-05-27 12:00 |
11:36:01.90 |
-34:53:07.4 |
HIP 56567 |
6.56 |
| 2026-05-28 00:00 |
11:36:00.87 |
-34:52:35.8 |
HIP 56567 |
5.99 |
| 2026-05-28 12:00 |
11:35:59.88 |
-34:52:04.1 |
HIP 56567 |
5.43 |
| 2026-05-29 00:00 |
11:35:58.91 |
-34:51:32.6 |
HIP 56567 |
4.87 |
| 2026-05-29 12:00 |
11:35:57.96 |
-34:51:01.1 |
HIP 56567 |
4.31 |
| 2026-05-30 00:00 |
11:35:57.05 |
-34:50:29.6 |
HIP 56567 |
3.76 |
| 2026-05-30 12:00 |
11:35:56.16 |
-34:49:58.3 |
HIP 56567 |
3.21 |
| 2026-05-31 00:00 |
11:35:55.30 |
-34:49:27.0 |
HIP 56567 |
2.67 |
| 2026-05-31 12:00 |
11:35:54.47 |
-34:48:55.8 |
HIP 56567 |
2.15 |
| 2026-06-01 00:00 |
11:35:53.67 |
-34:48:24.6 |
HIP 56567 |
1.64 |
| 2026-06-01 12:00 |
11:35:52.90 |
-34:47:53.5 |
HIP 56567 |
1.16 |
| 2026-06-02 00:00 |
11:35:52.15 |
-34:47:22.5 |
HIP 56567 |
0.79 |