| Parameter |
Value |
| Designation |
55P/Tempel-Tuttle |
| Type |
P |
| Perihelion (tp_cal, UTC) |
1998-02-28T02:20:44.226240Z |
| Orbit solution date (soln_date, UTC) |
2002-01-03T16:05:39Z |
| Obs used |
392 |
| NEO |
Yes |
| M1 |
10.000 |
| K1 |
25.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1998-08-15.0000000 |
| e |
0.90555272 |
| q (au) |
0.976428 |
| a (au) |
10.338338 |
| i (deg) |
162.486575 |
| Ω (om, deg) |
235.270989 |
| ω (w, deg) |
172.500274 |
| M (ma, deg) |
4.978340 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.795 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.795 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| 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 |
| 1996-05-12 |
1998-01-01 |
-1.9145 |
+1.548 |
| 1998-01-01 |
1998-01-27 |
+5.5017 |
-0.086 |
| 1998-01-27 |
1998-02-28 |
+19.7139 |
-0.354 |
| 1998-02-28 |
1998-07-05 |
+8.1609 |
-1.479 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
14:41:22.63 |
-11:33:25.5 |
HIP 71808 |
11.60 |
| 2026-06-01 12:00 |
14:41:13.04 |
-11:32:40.4 |
HIP 71808 |
10.92 |
| 2026-06-02 00:00 |
14:41:03.49 |
-11:31:55.6 |
HIP 71808 |
10.77 |
| 2026-06-02 12:00 |
14:40:53.98 |
-11:31:11.1 |
HIP 71808 |
11.16 |
| 2026-06-03 00:00 |
14:40:44.52 |
-11:30:26.8 |
HIP 71808 |
12.05 |
| 2026-06-03 12:00 |
14:40:35.10 |
-11:29:42.7 |
HIP 71808 |
13.32 |
| 2026-06-04 00:00 |
14:40:25.73 |
-11:28:59.0 |
HIP 71808 |
14.88 |
| 2026-06-04 12:00 |
14:40:16.40 |
-11:28:15.5 |
HIP 71646 |
16.55 |
| 2026-06-05 00:00 |
14:40:07.12 |
-11:27:32.2 |
HIP 71646 |
14.93 |
| 2026-06-05 12:00 |
14:39:57.88 |
-11:26:49.3 |
HIP 71646 |
13.55 |
| 2026-06-06 00:00 |
14:39:48.70 |
-11:26:06.6 |
HIP 71646 |
12.47 |
| 2026-06-06 12:00 |
14:39:39.56 |
-11:25:24.2 |
HIP 71646 |
11.78 |
| 2026-06-07 00:00 |
14:39:30.47 |
-11:24:42.1 |
HIP 71646 |
11.53 |
| 2026-06-07 12:00 |
14:39:21.44 |
-11:24:00.3 |
HIP 71646 |
11.75 |
| 2026-06-08 00:00 |
14:39:12.45 |
-11:23:18.8 |
HIP 71646 |
12.40 |
| 2026-06-08 12:00 |
14:39:03.51 |
-11:22:37.6 |
HIP 71646 |
13.41 |
| 2026-06-09 00:00 |
14:38:54.63 |
-11:21:56.7 |
HIP 71646 |
14.70 |
| 2026-06-09 12:00 |
14:38:45.80 |
-11:21:16.0 |
HIP 71646 |
16.20 |
| 2026-06-10 00:00 |
14:38:37.02 |
-11:20:35.7 |
HIP 71646 |
17.86 |
| 2026-06-10 12:00 |
14:38:28.29 |
-11:19:55.7 |
HIP 71646 |
19.62 |
| 2026-06-11 00:00 |
14:38:19.62 |
-11:19:16.0 |
HIP 71646 |
21.46 |
| 2026-06-11 12:00 |
14:38:11.01 |
-11:18:36.6 |
HIP 71646 |
23.35 |
| 2026-06-12 00:00 |
14:38:02.45 |
-11:17:57.5 |
HIP 71646 |
25.28 |
| 2026-06-12 12:00 |
14:37:53.94 |
-11:17:18.8 |
HIP 71646 |
27.24 |
| 2026-06-13 00:00 |
14:37:45.50 |
-11:16:40.3 |
HIP 71451 |
26.74 |
| 2026-06-13 12:00 |
14:37:37.11 |
-11:16:02.2 |
HIP 71451 |
26.17 |
| 2026-06-14 00:00 |
14:37:28.78 |
-11:15:24.4 |
HIP 71451 |
25.76 |
| 2026-06-14 12:00 |
14:37:20.51 |
-11:14:47.0 |
HIP 71375 |
24.82 |
| 2026-06-15 00:00 |
14:37:12.30 |
-11:14:09.9 |
HIP 71375 |
23.23 |
| 2026-06-15 12:00 |
14:37:04.15 |
-11:13:33.1 |
HIP 71375 |
21.74 |
| 2026-06-16 00:00 |
14:36:56.06 |
-11:12:56.7 |
HIP 71375 |
20.37 |
| 2026-06-16 12:00 |
14:36:48.03 |
-11:12:20.6 |
HIP 71375 |
19.13 |
| 2026-06-17 00:00 |
14:36:40.06 |
-11:11:44.8 |
HIP 71375 |
18.04 |
| 2026-06-17 12:00 |
14:36:32.16 |
-11:11:09.4 |
HIP 71375 |
17.14 |
| 2026-06-18 00:00 |
14:36:24.31 |
-11:10:34.3 |
HIP 71375 |
16.44 |
| 2026-06-18 12:00 |
14:36:16.54 |
-11:09:59.6 |
HIP 71375 |
15.97 |
| 2026-06-19 00:00 |
14:36:08.82 |
-11:09:25.2 |
HIP 71375 |
15.74 |
| 2026-06-19 12:00 |
14:36:01.17 |
-11:08:51.2 |
HIP 71375 |
15.75 |
| 2026-06-20 00:00 |
14:35:53.59 |
-11:08:17.6 |
HIP 71375 |
16.00 |
| 2026-06-20 12:00 |
14:35:46.07 |
-11:07:44.3 |
HIP 71375 |
16.47 |
| 2026-06-21 00:00 |
14:35:38.61 |
-11:07:11.3 |
HIP 71375 |
17.13 |
| 2026-06-21 12:00 |
14:35:31.23 |
-11:06:38.7 |
HIP 71375 |
17.97 |
| 2026-06-22 00:00 |
14:35:23.91 |
-11:06:06.5 |
HIP 71290 |
16.61 |