| Parameter |
Value |
| Designation |
C/1997 D1 (Mueller) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1997-10-11T14:47:59.519040Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:50Z |
| Obs used |
430 |
| NEO |
- |
| M1 |
6.000 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1997-07-13.0000000 |
| e |
1.00115666 |
| q (au) |
2.247622 |
| a (au) |
-1943.197807 |
| i (deg) |
141.889605 |
| Ω (om, deg) |
279.171154 |
| ω (w, deg) |
184.962587 |
| M (ma, deg) |
-0.001043 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.367 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.367 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.611 |
| k |
0.988 |
| 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 |
| 1997-02-17 |
1997-10-11 |
-0.9369 |
+0.030 |
| 1997-10-12 |
1998-09-02 |
+6.9714 |
-2.273 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
19:55:27.96 |
-33:01:09.8 |
HIP 98012 |
5.05 |
| 2026-07-29 12:00 |
19:55:25.15 |
-33:01:14.5 |
HIP 98012 |
4.47 |
| 2026-07-30 00:00 |
19:55:22.35 |
-33:01:19.0 |
HIP 98012 |
3.90 |
| 2026-07-30 12:00 |
19:55:19.55 |
-33:01:23.5 |
HIP 98012 |
3.33 |
| 2026-07-31 00:00 |
19:55:16.75 |
-33:01:27.9 |
HIP 98012 |
2.77 |
| 2026-07-31 12:00 |
19:55:13.96 |
-33:01:32.2 |
HIP 98012 |
2.23 |
| 2026-08-01 00:00 |
19:55:11.17 |
-33:01:36.4 |
HIP 98012 |
1.73 |
| 2026-08-01 12:00 |
19:55:08.39 |
-33:01:40.6 |
HIP 98012 |
1.30 |
| 2026-08-02 00:00 |
19:55:05.61 |
-33:01:44.7 |
HIP 98012 |
1.04 |
| 2026-08-02 12:00 |
19:55:02.84 |
-33:01:48.7 |
HIP 98012 |
1.07 |
| 2026-08-03 00:00 |
19:55:00.07 |
-33:01:52.6 |
HIP 98012 |
1.39 |
| 2026-08-03 12:00 |
19:54:57.31 |
-33:01:56.5 |
HIP 98012 |
1.83 |
| 2026-08-04 00:00 |
19:54:54.56 |
-33:02:00.2 |
HIP 98012 |
2.34 |
| 2026-08-04 12:00 |
19:54:51.81 |
-33:02:03.9 |
HIP 98012 |
2.88 |
| 2026-08-05 00:00 |
19:54:49.07 |
-33:02:07.6 |
HIP 98012 |
3.42 |
| 2026-08-05 12:00 |
19:54:46.33 |
-33:02:11.1 |
HIP 98012 |
3.98 |
| 2026-08-06 00:00 |
19:54:43.60 |
-33:02:14.6 |
HIP 98012 |
4.54 |
| 2026-08-06 12:00 |
19:54:40.88 |
-33:02:17.9 |
HIP 98012 |
5.10 |
| 2026-08-07 00:00 |
19:54:38.17 |
-33:02:21.2 |
HIP 98012 |
5.66 |
| 2026-08-07 12:00 |
19:54:35.46 |
-33:02:24.4 |
HIP 98012 |
6.22 |
| 2026-08-08 00:00 |
19:54:32.76 |
-33:02:27.6 |
HIP 98012 |
6.79 |
| 2026-08-08 12:00 |
19:54:30.07 |
-33:02:30.6 |
HIP 98012 |
7.35 |
| 2026-08-09 00:00 |
19:54:27.38 |
-33:02:33.6 |
HIP 98012 |
7.91 |
| 2026-08-09 12:00 |
19:54:24.71 |
-33:02:36.5 |
HIP 98012 |
8.47 |
| 2026-08-10 00:00 |
19:54:22.04 |
-33:02:39.3 |
HIP 98012 |
9.03 |
| 2026-08-10 12:00 |
19:54:19.38 |
-33:02:42.0 |
HIP 98012 |
9.58 |
| 2026-08-11 00:00 |
19:54:16.73 |
-33:02:44.7 |
HIP 98012 |
10.14 |
| 2026-08-11 12:00 |
19:54:14.09 |
-33:02:47.2 |
HIP 98012 |
10.69 |
| 2026-08-12 00:00 |
19:54:11.46 |
-33:02:49.7 |
HIP 98012 |
11.24 |
| 2026-08-12 12:00 |
19:54:08.84 |
-33:02:52.1 |
HIP 98012 |
11.79 |
| 2026-08-13 00:00 |
19:54:06.22 |
-33:02:54.4 |
HIP 98012 |
12.34 |
| 2026-08-13 12:00 |
19:54:03.62 |
-33:02:56.6 |
HIP 98012 |
12.89 |
| 2026-08-14 00:00 |
19:54:01.03 |
-33:02:58.8 |
HIP 98012 |
13.43 |
| 2026-08-14 12:00 |
19:53:58.44 |
-33:03:00.8 |
HIP 98012 |
13.97 |
| 2026-08-15 00:00 |
19:53:55.87 |
-33:03:02.8 |
HIP 98012 |
14.51 |
| 2026-08-15 12:00 |
19:53:53.31 |
-33:03:04.7 |
HIP 98012 |
15.05 |
| 2026-08-16 00:00 |
19:53:50.76 |
-33:03:06.5 |
HIP 98012 |
15.58 |
| 2026-08-16 12:00 |
19:53:48.22 |
-33:03:08.2 |
HIP 98012 |
16.12 |
| 2026-08-17 00:00 |
19:53:45.69 |
-33:03:09.8 |
HIP 98012 |
16.65 |
| 2026-08-17 12:00 |
19:53:43.17 |
-33:03:11.4 |
HIP 98012 |
17.18 |
| 2026-08-18 00:00 |
19:53:40.67 |
-33:03:12.8 |
HIP 98012 |
17.70 |
| 2026-08-18 12:00 |
19:53:38.17 |
-33:03:14.2 |
HIP 98012 |
18.22 |
| 2026-08-19 00:00 |
19:53:35.69 |
-33:03:15.5 |
HIP 98012 |
18.74 |