| Parameter |
Value |
| Designation |
110P/Hartley 3 |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2014-12-16T16:15:29.649600Z |
| Orbit solution date (soln_date, UTC) |
2023-05-22T13:49:16Z |
| Obs used |
2416 |
| NEO |
- |
| M1 |
4.300 |
| K1 |
26.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2018-05-08.0000000 |
| e |
0.31628027 |
| q (au) |
2.464450 |
| a (au) |
3.604474 |
| i (deg) |
11.698362 |
| Ω (om, deg) |
287.529573 |
| ω (w, deg) |
167.395612 |
| M (ma, deg) |
178.350762 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.184 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.184 |
| n |
6.000 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2019-07-25 |
2021-01-23 |
+35.2820 |
-14.426 |
| 2021-01-23 |
2023-05-13 |
-10.1067 |
+6.783 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
21:05:07.92 |
-13:23:53.3 |
HIP 104198 |
22.74 |
| 2026-03-26 12:00 |
21:05:31.53 |
-13:21:27.3 |
HIP 104198 |
18.34 |
| 2026-03-27 00:00 |
21:05:55.03 |
-13:19:01.2 |
HIP 104198 |
15.29 |
| 2026-03-27 12:00 |
21:06:18.44 |
-13:16:35.3 |
HIP 104198 |
14.44 |
| 2026-03-28 00:00 |
21:06:41.74 |
-13:14:09.4 |
HIP 104198 |
16.12 |
| 2026-03-28 12:00 |
21:07:04.95 |
-13:11:43.5 |
HIP 104198 |
19.67 |
| 2026-03-29 00:00 |
21:07:28.04 |
-13:09:17.7 |
HIP 104343 |
20.10 |
| 2026-03-29 12:00 |
21:07:51.04 |
-13:06:52.0 |
HIP 104343 |
15.23 |
| 2026-03-30 00:00 |
21:08:13.93 |
-13:04:26.4 |
HIP 104343 |
11.60 |
| 2026-03-30 12:00 |
21:08:36.72 |
-13:02:00.8 |
HIP 104343 |
10.53 |
| 2026-03-31 00:00 |
21:08:59.40 |
-12:59:35.3 |
HIP 104343 |
12.65 |
| 2026-03-31 12:00 |
21:09:21.97 |
-12:57:09.9 |
HIP 104493 |
16.63 |
| 2026-04-01 00:00 |
21:09:44.44 |
-12:54:44.7 |
HIP 104493 |
16.43 |
| 2026-04-01 12:00 |
21:10:06.80 |
-12:52:19.5 |
HIP 104465 |
15.64 |
| 2026-04-02 00:00 |
21:10:29.05 |
-12:49:54.4 |
HIP 104465 |
16.61 |
| 2026-04-02 12:00 |
21:10:51.20 |
-12:47:29.4 |
HIP 104465 |
19.42 |
| 2026-04-03 00:00 |
21:11:13.23 |
-12:45:04.5 |
HIP 104465 |
23.39 |
| 2026-04-03 12:00 |
21:11:35.15 |
-12:42:39.8 |
HIP 104465 |
28.02 |
| 2026-04-04 00:00 |
21:11:56.97 |
-12:40:15.1 |
HIP 104465 |
33.02 |
| 2026-04-04 12:00 |
21:12:18.67 |
-12:37:50.6 |
HIP 104817 |
28.30 |
| 2026-04-05 00:00 |
21:12:40.25 |
-12:35:26.3 |
HIP 104817 |
22.53 |
| 2026-04-05 12:00 |
21:13:01.73 |
-12:33:02.0 |
HIP 104817 |
16.80 |
| 2026-04-06 00:00 |
21:13:23.08 |
-12:30:38.0 |
HIP 104817 |
11.13 |
| 2026-04-06 12:00 |
21:13:44.33 |
-12:28:14.0 |
HIP 104817 |
5.63 |
| 2026-04-07 00:00 |
21:14:05.46 |
-12:25:50.2 |
HIP 104817 |
2.20 |
| 2026-04-07 12:00 |
21:14:26.47 |
-12:23:26.6 |
HIP 104817 |
6.51 |
| 2026-04-08 00:00 |
21:14:47.36 |
-12:21:03.2 |
HIP 104817 |
11.98 |
| 2026-04-08 12:00 |
21:15:08.13 |
-12:18:39.9 |
HIP 104817 |
17.52 |
| 2026-04-09 00:00 |
21:15:28.79 |
-12:16:16.8 |
HIP 104826 |
21.65 |
| 2026-04-09 12:00 |
21:15:49.32 |
-12:13:53.9 |
HIP 104826 |
25.23 |
| 2026-04-10 00:00 |
21:16:09.73 |
-12:11:31.1 |
HIP 104826 |
29.40 |
| 2026-04-10 12:00 |
21:16:30.02 |
-12:09:08.6 |
HIP 105189 |
30.10 |
| 2026-04-11 00:00 |
21:16:50.19 |
-12:06:46.3 |
HIP 105189 |
26.06 |
| 2026-04-11 12:00 |
21:17:10.23 |
-12:04:24.1 |
HIP 105189 |
22.65 |
| 2026-04-12 00:00 |
21:17:30.15 |
-12:02:02.2 |
HIP 105189 |
20.17 |
| 2026-04-12 12:00 |
21:17:49.94 |
-11:59:40.5 |
HIP 105189 |
18.97 |
| 2026-04-13 00:00 |
21:18:09.61 |
-11:57:19.1 |
HIP 105189 |
19.25 |
| 2026-04-13 12:00 |
21:18:29.15 |
-11:54:57.9 |
HIP 105189 |
20.95 |
| 2026-04-14 00:00 |
21:18:48.55 |
-11:52:36.9 |
HIP 105189 |
23.73 |
| 2026-04-14 12:00 |
21:19:07.83 |
-11:50:16.1 |
HIP 105189 |
27.26 |
| 2026-04-15 00:00 |
21:19:26.98 |
-11:47:55.6 |
HIP 105189 |
31.25 |
| 2026-04-15 12:00 |
21:19:45.99 |
-11:45:35.4 |
HIP 105387 |
29.07 |
| 2026-04-16 00:00 |
21:20:04.88 |
-11:43:15.5 |
HIP 105387 |
24.78 |