| Parameter |
Value |
| Designation |
C/2008 J1 (Boattini) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2008-07-13T06:16:45.272640Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:19Z |
| Obs used |
1557 |
| NEO |
- |
| M1 |
8.700 |
| K1 |
17.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2008-08-03.0000000 |
| e |
0.98961635 |
| q (au) |
1.724294 |
| a (au) |
166.058556 |
| i (deg) |
61.780021 |
| Ω (om, deg) |
273.419698 |
| ω (w, deg) |
68.122712 |
| M (ma, deg) |
0.009552 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.102 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.102 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.525 |
| 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 |
| 2008-05-02 |
2008-07-13 |
+2.4126 |
-0.690 |
| 2008-07-13 |
2009-04-04 |
+6.1030 |
-2.669 |
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 |
07:33:13.85 |
-15:49:35.6 |
HIP 36727 |
22.38 |
| 2026-07-29 12:00 |
07:33:17.06 |
-15:49:51.0 |
HIP 36727 |
22.65 |
| 2026-07-30 00:00 |
07:33:20.26 |
-15:50:06.6 |
HIP 36727 |
22.96 |
| 2026-07-30 12:00 |
07:33:23.45 |
-15:50:22.4 |
HIP 36727 |
23.29 |
| 2026-07-31 00:00 |
07:33:26.64 |
-15:50:38.4 |
HIP 36809 |
23.48 |
| 2026-07-31 12:00 |
07:33:29.81 |
-15:50:54.7 |
HIP 36809 |
22.89 |
| 2026-08-01 00:00 |
07:33:32.98 |
-15:51:11.1 |
HIP 36809 |
22.30 |
| 2026-08-01 12:00 |
07:33:36.15 |
-15:51:27.8 |
HIP 36809 |
21.73 |
| 2026-08-02 00:00 |
07:33:39.30 |
-15:51:44.7 |
HIP 36809 |
21.17 |
| 2026-08-02 12:00 |
07:33:42.45 |
-15:52:01.8 |
HIP 36809 |
20.62 |
| 2026-08-03 00:00 |
07:33:45.59 |
-15:52:19.2 |
HIP 36809 |
20.09 |
| 2026-08-03 12:00 |
07:33:48.71 |
-15:52:36.7 |
HIP 36809 |
19.58 |
| 2026-08-04 00:00 |
07:33:51.84 |
-15:52:54.5 |
HIP 36809 |
19.08 |
| 2026-08-04 12:00 |
07:33:54.95 |
-15:53:12.4 |
HIP 36809 |
18.60 |
| 2026-08-05 00:00 |
07:33:58.05 |
-15:53:30.6 |
HIP 36809 |
18.14 |
| 2026-08-05 12:00 |
07:34:01.14 |
-15:53:49.0 |
HIP 36809 |
17.71 |
| 2026-08-06 00:00 |
07:34:04.23 |
-15:54:07.6 |
HIP 36809 |
17.29 |
| 2026-08-06 12:00 |
07:34:07.30 |
-15:54:26.4 |
HIP 36809 |
16.91 |
| 2026-08-07 00:00 |
07:34:10.36 |
-15:54:45.4 |
HIP 36809 |
16.54 |
| 2026-08-07 12:00 |
07:34:13.42 |
-15:55:04.6 |
HIP 36809 |
16.21 |
| 2026-08-08 00:00 |
07:34:16.46 |
-15:55:24.0 |
HIP 36809 |
15.90 |
| 2026-08-08 12:00 |
07:34:19.49 |
-15:55:43.6 |
HIP 36809 |
15.63 |
| 2026-08-09 00:00 |
07:34:22.51 |
-15:56:03.4 |
HIP 36809 |
15.39 |
| 2026-08-09 12:00 |
07:34:25.53 |
-15:56:23.5 |
HIP 36809 |
15.19 |
| 2026-08-10 00:00 |
07:34:28.52 |
-15:56:43.7 |
HIP 36809 |
15.02 |
| 2026-08-10 12:00 |
07:34:31.51 |
-15:57:04.1 |
HIP 36809 |
14.88 |
| 2026-08-11 00:00 |
07:34:34.49 |
-15:57:24.8 |
HIP 36809 |
14.79 |
| 2026-08-11 12:00 |
07:34:37.45 |
-15:57:45.6 |
HIP 36809 |
14.73 |
| 2026-08-12 00:00 |
07:34:40.41 |
-15:58:06.6 |
HIP 36809 |
14.71 |
| 2026-08-12 12:00 |
07:34:43.35 |
-15:58:27.8 |
HIP 36809 |
14.72 |
| 2026-08-13 00:00 |
07:34:46.27 |
-15:58:49.2 |
HIP 36809 |
14.78 |
| 2026-08-13 12:00 |
07:34:49.19 |
-15:59:10.8 |
HIP 36809 |
14.87 |
| 2026-08-14 00:00 |
07:34:52.09 |
-15:59:32.6 |
HIP 36809 |
15.00 |
| 2026-08-14 12:00 |
07:34:54.98 |
-15:59:54.6 |
HIP 36809 |
15.17 |
| 2026-08-15 00:00 |
07:34:57.85 |
-16:00:16.8 |
HIP 36809 |
15.37 |
| 2026-08-15 12:00 |
07:35:00.72 |
-16:00:39.1 |
HIP 36809 |
15.60 |
| 2026-08-16 00:00 |
07:35:03.56 |
-16:01:01.7 |
HIP 36809 |
15.86 |
| 2026-08-16 12:00 |
07:35:06.40 |
-16:01:24.4 |
HIP 36809 |
16.15 |
| 2026-08-17 00:00 |
07:35:09.22 |
-16:01:47.3 |
HIP 36809 |
16.47 |
| 2026-08-17 12:00 |
07:35:12.02 |
-16:02:10.4 |
HIP 36809 |
16.81 |
| 2026-08-18 00:00 |
07:35:14.81 |
-16:02:33.7 |
HIP 36809 |
17.18 |
| 2026-08-18 12:00 |
07:35:17.59 |
-16:02:57.2 |
HIP 36809 |
17.57 |
| 2026-08-19 00:00 |
07:35:20.35 |
-16:03:20.8 |
HIP 36809 |
17.97 |