| Parameter |
Value |
| Designation |
270P/Gehrels |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2013-07-18T12:29:23.700480Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:28:10Z |
| Obs used |
381 |
| NEO |
- |
| M1 |
13.700 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2008-07-20.0000000 |
| e |
0.46760427 |
| q (au) |
3.594521 |
| a (au) |
6.751596 |
| i (deg) |
2.859570 |
| Ω (om, deg) |
225.681440 |
| ω (w, deg) |
211.476072 |
| M (ma, deg) |
257.495456 |
Magnitude
Scatter + Global Linear
$$
M_a = (7.051 + 5.884\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.051 |
| n |
5.884 |
| gf |
0.993 |
| gb |
-0.979 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
19:54:20.28 |
-17:31:51.6 |
HIP 98054 |
18.47 |
| 2026-07-29 12:00 |
19:54:07.97 |
-17:32:26.7 |
HIP 98054 |
21.36 |
| 2026-07-30 00:00 |
19:53:55.69 |
-17:33:01.8 |
HIP 98054 |
24.26 |
| 2026-07-30 12:00 |
19:53:43.43 |
-17:33:36.9 |
HIP 98054 |
27.17 |
| 2026-07-31 00:00 |
19:53:31.20 |
-17:34:12.0 |
HIP 98054 |
30.09 |
| 2026-07-31 12:00 |
19:53:18.99 |
-17:34:47.1 |
HIP 97740 |
29.21 |
| 2026-08-01 00:00 |
19:53:06.82 |
-17:35:22.1 |
HIP 97740 |
27.45 |
| 2026-08-01 12:00 |
19:52:54.68 |
-17:35:57.2 |
HIP 97740 |
25.92 |
| 2026-08-02 00:00 |
19:52:42.57 |
-17:36:32.3 |
HIP 97740 |
24.66 |
| 2026-08-02 12:00 |
19:52:30.49 |
-17:37:07.3 |
HIP 97740 |
23.69 |
| 2026-08-03 00:00 |
19:52:18.45 |
-17:37:42.3 |
HIP 97740 |
23.07 |
| 2026-08-03 12:00 |
19:52:06.45 |
-17:38:17.2 |
HIP 97740 |
22.82 |
| 2026-08-04 00:00 |
19:51:54.48 |
-17:38:52.2 |
HIP 97740 |
22.93 |
| 2026-08-04 12:00 |
19:51:42.56 |
-17:39:27.1 |
HIP 97740 |
23.41 |
| 2026-08-05 00:00 |
19:51:30.68 |
-17:40:01.9 |
HIP 97740 |
24.23 |
| 2026-08-05 12:00 |
19:51:18.85 |
-17:40:36.8 |
HIP 97596 |
22.70 |
| 2026-08-06 00:00 |
19:51:07.06 |
-17:41:11.5 |
HIP 97596 |
20.43 |
| 2026-08-06 12:00 |
19:50:55.31 |
-17:41:46.2 |
HIP 97596 |
18.34 |
| 2026-08-07 00:00 |
19:50:43.62 |
-17:42:20.9 |
HIP 97596 |
16.48 |
| 2026-08-07 12:00 |
19:50:31.97 |
-17:42:55.5 |
HIP 97596 |
14.94 |
| 2026-08-08 00:00 |
19:50:20.38 |
-17:43:30.0 |
HIP 97596 |
13.82 |
| 2026-08-08 12:00 |
19:50:08.84 |
-17:44:04.5 |
HIP 97596 |
13.21 |
| 2026-08-09 00:00 |
19:49:57.36 |
-17:44:38.9 |
HIP 97596 |
13.19 |
| 2026-08-09 12:00 |
19:49:45.93 |
-17:45:13.2 |
HIP 97596 |
13.73 |
| 2026-08-10 00:00 |
19:49:34.56 |
-17:45:47.4 |
HIP 97596 |
14.78 |
| 2026-08-10 12:00 |
19:49:23.25 |
-17:46:21.6 |
HIP 97596 |
16.23 |
| 2026-08-11 00:00 |
19:49:12.00 |
-17:46:55.6 |
HIP 97596 |
17.98 |
| 2026-08-11 12:00 |
19:49:00.82 |
-17:47:29.6 |
HIP 97596 |
19.93 |
| 2026-08-12 00:00 |
19:48:49.70 |
-17:48:03.4 |
HIP 97596 |
22.04 |
| 2026-08-12 12:00 |
19:48:38.65 |
-17:48:37.2 |
HIP 97419 |
21.82 |
| 2026-08-13 00:00 |
19:48:27.66 |
-17:49:10.8 |
HIP 97419 |
21.40 |
| 2026-08-13 12:00 |
19:48:16.74 |
-17:49:44.4 |
HIP 97419 |
21.31 |
| 2026-08-14 00:00 |
19:48:05.90 |
-17:50:17.8 |
HIP 97419 |
21.54 |
| 2026-08-14 12:00 |
19:47:55.13 |
-17:50:51.1 |
HIP 97419 |
22.09 |
| 2026-08-15 00:00 |
19:47:44.43 |
-17:51:24.3 |
HIP 97419 |
22.93 |
| 2026-08-15 12:00 |
19:47:33.80 |
-17:51:57.3 |
HIP 97296 |
23.53 |
| 2026-08-16 00:00 |
19:47:23.26 |
-17:52:30.2 |
HIP 97296 |
21.46 |
| 2026-08-16 12:00 |
19:47:12.79 |
-17:53:03.0 |
HIP 97296 |
19.52 |
| 2026-08-17 00:00 |
19:47:02.40 |
-17:53:35.6 |
HIP 97296 |
17.76 |
| 2026-08-17 12:00 |
19:46:52.09 |
-17:54:08.1 |
HIP 97296 |
16.20 |
| 2026-08-18 00:00 |
19:46:41.87 |
-17:54:40.5 |
HIP 97296 |
14.91 |
| 2026-08-18 12:00 |
19:46:31.73 |
-17:55:12.7 |
HIP 97296 |
13.96 |
| 2026-08-19 00:00 |
19:46:21.67 |
-17:55:44.7 |
HIP 97296 |
13.40 |