| 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) |
| 2026-05-12 00:00 |
14:48:12.54 |
-12:06:17.3 |
HIP 72596 |
35.51 |
| 2026-05-12 12:00 |
14:48:01.89 |
-12:05:24.9 |
HIP 72301 |
35.14 |
| 2026-05-13 00:00 |
14:47:51.24 |
-12:04:32.7 |
HIP 72301 |
33.39 |
| 2026-05-13 12:00 |
14:47:40.61 |
-12:03:40.6 |
HIP 72301 |
31.77 |
| 2026-05-14 00:00 |
14:47:29.98 |
-12:02:48.6 |
HIP 72301 |
30.33 |
| 2026-05-14 12:00 |
14:47:19.37 |
-12:01:56.7 |
HIP 72301 |
29.07 |
| 2026-05-15 00:00 |
14:47:08.77 |
-12:01:04.9 |
HIP 72301 |
28.02 |
| 2026-05-15 12:00 |
14:46:58.19 |
-12:00:13.3 |
HIP 72301 |
27.22 |
| 2026-05-16 00:00 |
14:46:47.62 |
-11:59:21.8 |
HIP 72301 |
26.67 |
| 2026-05-16 12:00 |
14:46:37.07 |
-11:58:30.4 |
HIP 72174 |
26.10 |
| 2026-05-17 00:00 |
14:46:26.53 |
-11:57:39.1 |
HIP 72174 |
25.71 |
| 2026-05-17 12:00 |
14:46:16.01 |
-11:56:48.0 |
HIP 72174 |
25.61 |
| 2026-05-18 00:00 |
14:46:05.51 |
-11:55:57.1 |
HIP 72174 |
25.79 |
| 2026-05-18 12:00 |
14:45:55.03 |
-11:55:06.2 |
HIP 72174 |
26.24 |
| 2026-05-19 00:00 |
14:45:44.57 |
-11:54:15.6 |
HIP 72023 |
26.51 |
| 2026-05-19 12:00 |
14:45:34.13 |
-11:53:25.1 |
HIP 72023 |
23.92 |
| 2026-05-20 00:00 |
14:45:23.72 |
-11:52:34.8 |
HIP 72023 |
21.35 |
| 2026-05-20 12:00 |
14:45:13.33 |
-11:51:44.6 |
HIP 72023 |
18.82 |
| 2026-05-21 00:00 |
14:45:02.96 |
-11:50:54.6 |
HIP 72023 |
16.35 |
| 2026-05-21 12:00 |
14:44:52.62 |
-11:50:04.8 |
HIP 72023 |
13.95 |
| 2026-05-22 00:00 |
14:44:42.30 |
-11:49:15.2 |
HIP 72023 |
11.67 |
| 2026-05-22 12:00 |
14:44:32.01 |
-11:48:25.7 |
HIP 72023 |
9.59 |
| 2026-05-23 00:00 |
14:44:21.75 |
-11:47:36.4 |
HIP 72023 |
7.87 |
| 2026-05-23 12:00 |
14:44:11.51 |
-11:46:47.4 |
HIP 72023 |
6.77 |
| 2026-05-24 00:00 |
14:44:01.31 |
-11:45:58.5 |
HIP 72023 |
6.60 |
| 2026-05-24 12:00 |
14:43:51.13 |
-11:45:09.8 |
HIP 72023 |
7.42 |
| 2026-05-25 00:00 |
14:43:40.99 |
-11:44:21.3 |
HIP 72023 |
8.95 |
| 2026-05-25 12:00 |
14:43:30.88 |
-11:43:33.0 |
HIP 72023 |
10.89 |
| 2026-05-26 00:00 |
14:43:20.80 |
-11:42:45.0 |
HIP 72023 |
13.06 |
| 2026-05-26 12:00 |
14:43:10.75 |
-11:41:57.1 |
HIP 72023 |
15.35 |
| 2026-05-27 00:00 |
14:43:00.74 |
-11:41:09.4 |
HIP 72023 |
17.71 |
| 2026-05-27 12:00 |
14:42:50.76 |
-11:40:22.0 |
HIP 72023 |
20.12 |
| 2026-05-28 00:00 |
14:42:40.82 |
-11:39:34.8 |
HIP 72023 |
22.55 |
| 2026-05-28 12:00 |
14:42:30.91 |
-11:38:47.8 |
HIP 71808 |
24.44 |
| 2026-05-29 00:00 |
14:42:21.04 |
-11:38:01.1 |
HIP 71808 |
22.18 |
| 2026-05-29 12:00 |
14:42:11.21 |
-11:37:14.5 |
HIP 71808 |
20.01 |
| 2026-05-30 00:00 |
14:42:01.41 |
-11:36:28.3 |
HIP 71808 |
17.93 |
| 2026-05-30 12:00 |
14:41:51.66 |
-11:35:42.2 |
HIP 71808 |
15.99 |
| 2026-05-31 00:00 |
14:41:41.94 |
-11:34:56.4 |
HIP 71808 |
14.24 |
| 2026-05-31 12:00 |
14:41:32.27 |
-11:34:10.8 |
HIP 71808 |
12.75 |
| 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 |