| Parameter |
Value |
| Designation |
C/2009 U5 (Grauer) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2010-06-22T11:50:14.052480Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:37Z |
| Obs used |
182 |
| NEO |
- |
| M1 |
11.800 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2010-02-02.0000000 |
| e |
0.99942402 |
| q (au) |
6.094240 |
| a (au) |
10580.667509 |
| i (deg) |
25.472676 |
| Ω (om, deg) |
121.174091 |
| ω (w, deg) |
23.813513 |
| M (ma, deg) |
359.999873 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.379 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.379 |
| n |
2.000 |
| 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) |
| 2026-06-01 00:00 |
18:20:50.13 |
-10:56:07.6 |
HIP 89800 |
17.91 |
| 2026-06-01 12:00 |
18:20:46.93 |
-10:56:06.6 |
HIP 89800 |
17.12 |
| 2026-06-02 00:00 |
18:20:43.72 |
-10:56:05.8 |
HIP 89800 |
16.34 |
| 2026-06-02 12:00 |
18:20:40.50 |
-10:56:05.1 |
HIP 89800 |
15.55 |
| 2026-06-03 00:00 |
18:20:37.26 |
-10:56:04.4 |
HIP 89800 |
14.75 |
| 2026-06-03 12:00 |
18:20:34.01 |
-10:56:03.9 |
HIP 89800 |
13.95 |
| 2026-06-04 00:00 |
18:20:30.75 |
-10:56:03.4 |
HIP 89800 |
13.15 |
| 2026-06-04 12:00 |
18:20:27.47 |
-10:56:03.1 |
HIP 89800 |
12.35 |
| 2026-06-05 00:00 |
18:20:24.18 |
-10:56:02.9 |
HIP 89800 |
11.54 |
| 2026-06-05 12:00 |
18:20:20.88 |
-10:56:02.8 |
HIP 89800 |
10.73 |
| 2026-06-06 00:00 |
18:20:17.57 |
-10:56:02.7 |
HIP 89800 |
9.92 |
| 2026-06-06 12:00 |
18:20:14.25 |
-10:56:02.8 |
HIP 89800 |
9.10 |
| 2026-06-07 00:00 |
18:20:10.91 |
-10:56:03.0 |
HIP 89800 |
8.28 |
| 2026-06-07 12:00 |
18:20:07.56 |
-10:56:03.3 |
HIP 89800 |
7.46 |
| 2026-06-08 00:00 |
18:20:04.20 |
-10:56:03.7 |
HIP 89800 |
6.64 |
| 2026-06-08 12:00 |
18:20:00.84 |
-10:56:04.2 |
HIP 89800 |
5.81 |
| 2026-06-09 00:00 |
18:19:57.46 |
-10:56:04.8 |
HIP 89800 |
4.98 |
| 2026-06-09 12:00 |
18:19:54.07 |
-10:56:05.5 |
HIP 89800 |
4.15 |
| 2026-06-10 00:00 |
18:19:50.67 |
-10:56:06.3 |
HIP 89800 |
3.32 |
| 2026-06-10 12:00 |
18:19:47.26 |
-10:56:07.2 |
HIP 89800 |
2.48 |
| 2026-06-11 00:00 |
18:19:43.84 |
-10:56:08.3 |
HIP 89800 |
1.64 |
| 2026-06-11 12:00 |
18:19:40.42 |
-10:56:09.4 |
HIP 89800 |
0.81 |
| 2026-06-12 00:00 |
18:19:36.98 |
-10:56:10.6 |
HIP 89800 |
0.18 |
| 2026-06-12 12:00 |
18:19:33.54 |
-10:56:12.0 |
HIP 89800 |
0.91 |
| 2026-06-13 00:00 |
18:19:30.09 |
-10:56:13.4 |
HIP 89800 |
1.75 |
| 2026-06-13 12:00 |
18:19:26.63 |
-10:56:15.0 |
HIP 89800 |
2.60 |
| 2026-06-14 00:00 |
18:19:23.16 |
-10:56:16.7 |
HIP 89800 |
3.45 |
| 2026-06-14 12:00 |
18:19:19.69 |
-10:56:18.4 |
HIP 89800 |
4.30 |
| 2026-06-15 00:00 |
18:19:16.21 |
-10:56:20.3 |
HIP 89800 |
5.15 |
| 2026-06-15 12:00 |
18:19:12.73 |
-10:56:22.3 |
HIP 89800 |
6.01 |
| 2026-06-16 00:00 |
18:19:09.23 |
-10:56:24.4 |
HIP 89800 |
6.87 |
| 2026-06-16 12:00 |
18:19:05.74 |
-10:56:26.6 |
HIP 89800 |
7.73 |
| 2026-06-17 00:00 |
18:19:02.23 |
-10:56:28.9 |
HIP 89800 |
8.59 |
| 2026-06-17 12:00 |
18:18:58.73 |
-10:56:31.3 |
HIP 89800 |
9.45 |
| 2026-06-18 00:00 |
18:18:55.21 |
-10:56:33.8 |
HIP 89800 |
10.31 |
| 2026-06-18 12:00 |
18:18:51.70 |
-10:56:36.4 |
HIP 89800 |
11.18 |
| 2026-06-19 00:00 |
18:18:48.18 |
-10:56:39.1 |
HIP 89800 |
12.04 |
| 2026-06-19 12:00 |
18:18:44.65 |
-10:56:42.0 |
HIP 89800 |
12.91 |
| 2026-06-20 00:00 |
18:18:41.12 |
-10:56:44.9 |
HIP 89800 |
13.78 |
| 2026-06-20 12:00 |
18:18:37.59 |
-10:56:47.9 |
HIP 89800 |
14.65 |
| 2026-06-21 00:00 |
18:18:34.06 |
-10:56:51.1 |
HIP 89800 |
15.51 |
| 2026-06-21 12:00 |
18:18:30.52 |
-10:56:54.3 |
HIP 89800 |
16.38 |
| 2026-06-22 00:00 |
18:18:26.98 |
-10:56:57.7 |
HIP 89800 |
17.25 |