| 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
$$
M_a = (9.368 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.368 |
| n |
2.000 |
| gf |
0.999 |
| 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 |
-0.9370 |
+0.030 |
| 1997-10-12 |
1998-09-02 |
+6.9718 |
-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) |
| 2026-05-12 00:00 |
20:01:29.16 |
-32:39:52.4 |
HIP 98480 |
25.34 |
| 2026-05-12 12:00 |
20:01:28.01 |
-32:40:01.2 |
HIP 98480 |
25.09 |
| 2026-05-13 00:00 |
20:01:26.85 |
-32:40:10.1 |
HIP 98480 |
24.83 |
| 2026-05-13 12:00 |
20:01:25.66 |
-32:40:19.0 |
HIP 98480 |
24.58 |
| 2026-05-14 00:00 |
20:01:24.45 |
-32:40:27.9 |
HIP 98480 |
24.32 |
| 2026-05-14 12:00 |
20:01:23.22 |
-32:40:36.9 |
HIP 98480 |
24.06 |
| 2026-05-15 00:00 |
20:01:21.97 |
-32:40:45.9 |
HIP 98480 |
23.80 |
| 2026-05-15 12:00 |
20:01:20.69 |
-32:40:54.9 |
HIP 98480 |
23.53 |
| 2026-05-16 00:00 |
20:01:19.40 |
-32:41:04.0 |
HIP 98480 |
23.27 |
| 2026-05-16 12:00 |
20:01:18.08 |
-32:41:13.0 |
HIP 98480 |
23.00 |
| 2026-05-17 00:00 |
20:01:16.74 |
-32:41:22.1 |
HIP 98480 |
22.73 |
| 2026-05-17 12:00 |
20:01:15.39 |
-32:41:31.3 |
HIP 98480 |
22.46 |
| 2026-05-18 00:00 |
20:01:14.01 |
-32:41:40.4 |
HIP 98480 |
22.19 |
| 2026-05-18 12:00 |
20:01:12.61 |
-32:41:49.6 |
HIP 98480 |
21.92 |
| 2026-05-19 00:00 |
20:01:11.18 |
-32:41:58.8 |
HIP 98480 |
21.65 |
| 2026-05-19 12:00 |
20:01:09.74 |
-32:42:08.0 |
HIP 98480 |
21.38 |
| 2026-05-20 00:00 |
20:01:08.28 |
-32:42:17.2 |
HIP 98480 |
21.11 |
| 2026-05-20 12:00 |
20:01:06.80 |
-32:42:26.5 |
HIP 98480 |
20.83 |
| 2026-05-21 00:00 |
20:01:05.29 |
-32:42:35.8 |
HIP 98480 |
20.56 |
| 2026-05-21 12:00 |
20:01:03.77 |
-32:42:45.0 |
HIP 98480 |
20.29 |
| 2026-05-22 00:00 |
20:01:02.23 |
-32:42:54.3 |
HIP 98480 |
20.02 |
| 2026-05-22 12:00 |
20:01:00.67 |
-32:43:03.7 |
HIP 98480 |
19.75 |
| 2026-05-23 00:00 |
20:00:59.08 |
-32:43:13.0 |
HIP 98480 |
19.48 |
| 2026-05-23 12:00 |
20:00:57.48 |
-32:43:22.4 |
HIP 98480 |
19.22 |
| 2026-05-24 00:00 |
20:00:55.86 |
-32:43:31.7 |
HIP 98480 |
18.95 |
| 2026-05-24 12:00 |
20:00:54.22 |
-32:43:41.1 |
HIP 98480 |
18.69 |
| 2026-05-25 00:00 |
20:00:52.56 |
-32:43:50.5 |
HIP 98480 |
18.43 |
| 2026-05-25 12:00 |
20:00:50.87 |
-32:43:59.9 |
HIP 98480 |
18.17 |
| 2026-05-26 00:00 |
20:00:49.18 |
-32:44:09.3 |
HIP 98480 |
17.92 |
| 2026-05-26 12:00 |
20:00:47.46 |
-32:44:18.7 |
HIP 98480 |
17.67 |
| 2026-05-27 00:00 |
20:00:45.72 |
-32:44:28.1 |
HIP 98480 |
17.42 |
| 2026-05-27 12:00 |
20:00:43.96 |
-32:44:37.6 |
HIP 98480 |
17.18 |
| 2026-05-28 00:00 |
20:00:42.19 |
-32:44:47.0 |
HIP 98480 |
16.94 |
| 2026-05-28 12:00 |
20:00:40.40 |
-32:44:56.5 |
HIP 98480 |
16.71 |
| 2026-05-29 00:00 |
20:00:38.59 |
-32:45:05.9 |
HIP 98480 |
16.49 |
| 2026-05-29 12:00 |
20:00:36.76 |
-32:45:15.4 |
HIP 98480 |
16.27 |
| 2026-05-30 00:00 |
20:00:34.91 |
-32:45:24.9 |
HIP 98480 |
16.06 |
| 2026-05-30 12:00 |
20:00:33.04 |
-32:45:34.3 |
HIP 98480 |
15.86 |
| 2026-05-31 00:00 |
20:00:31.16 |
-32:45:43.8 |
HIP 98480 |
15.67 |
| 2026-05-31 12:00 |
20:00:29.26 |
-32:45:53.3 |
HIP 98480 |
15.48 |
| 2026-06-01 00:00 |
20:00:27.34 |
-32:46:02.8 |
HIP 98480 |
15.30 |
| 2026-06-01 12:00 |
20:00:25.40 |
-32:46:12.2 |
HIP 98480 |
15.14 |
| 2026-06-02 00:00 |
20:00:23.45 |
-32:46:21.7 |
HIP 98480 |
14.99 |