| Parameter |
Value |
| Designation |
C/1968 Q1 (Bally-Clayton) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1968-08-20T20:17:35.787840Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:19Z |
| Obs used |
52 |
| NEO |
- |
| M1 |
8.500 |
| K1 |
6.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1968-09-19.0000000 |
| e |
1.00000000 |
| q (au) |
1.771094 |
| a (au) |
- |
| i (deg) |
93.169377 |
| Ω (om, deg) |
319.395346 |
| ω (w, deg) |
26.864965 |
| M (ma, deg) |
- |
Magnitude
Scatter + Global Linear
$$
M_a = (7.710 + 5.798\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.710 |
| n |
5.798 |
| gf |
1.000 |
| gb |
-0.782 |
| k |
0.800 |
| δ90 |
9.999 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
09:12:01.09 |
+05:45:43.3 |
HIP 45150 |
17.65 |
| 2026-07-29 12:00 |
09:12:02.41 |
+05:45:37.4 |
HIP 45150 |
17.58 |
| 2026-07-30 00:00 |
09:12:03.72 |
+05:45:31.5 |
HIP 45150 |
17.52 |
| 2026-07-30 12:00 |
09:12:05.04 |
+05:45:25.5 |
HIP 45150 |
17.46 |
| 2026-07-31 00:00 |
09:12:06.36 |
+05:45:19.6 |
HIP 45150 |
17.41 |
| 2026-07-31 12:00 |
09:12:07.68 |
+05:45:13.5 |
HIP 45150 |
17.36 |
| 2026-08-01 00:00 |
09:12:09.00 |
+05:45:07.5 |
HIP 45150 |
17.32 |
| 2026-08-01 12:00 |
09:12:10.33 |
+05:45:01.4 |
HIP 45150 |
17.29 |
| 2026-08-02 00:00 |
09:12:11.65 |
+05:44:55.2 |
HIP 45150 |
17.26 |
| 2026-08-02 12:00 |
09:12:12.98 |
+05:44:49.1 |
HIP 45150 |
17.24 |
| 2026-08-03 00:00 |
09:12:14.30 |
+05:44:42.8 |
HIP 45150 |
17.23 |
| 2026-08-03 12:00 |
09:12:15.63 |
+05:44:36.6 |
HIP 45150 |
17.22 |
| 2026-08-04 00:00 |
09:12:16.96 |
+05:44:30.3 |
HIP 45252 |
16.98 |
| 2026-08-04 12:00 |
09:12:18.29 |
+05:44:24.0 |
HIP 45252 |
16.69 |
| 2026-08-05 00:00 |
09:12:19.62 |
+05:44:17.6 |
HIP 45252 |
16.40 |
| 2026-08-05 12:00 |
09:12:20.95 |
+05:44:11.2 |
HIP 45252 |
16.12 |
| 2026-08-06 00:00 |
09:12:22.29 |
+05:44:04.8 |
HIP 45252 |
15.83 |
| 2026-08-06 12:00 |
09:12:23.62 |
+05:43:58.3 |
HIP 45252 |
15.55 |
| 2026-08-07 00:00 |
09:12:24.95 |
+05:43:51.9 |
HIP 45252 |
15.27 |
| 2026-08-07 12:00 |
09:12:26.28 |
+05:43:45.3 |
HIP 45252 |
15.00 |
| 2026-08-08 00:00 |
09:12:27.62 |
+05:43:38.8 |
HIP 45252 |
14.73 |
| 2026-08-08 12:00 |
09:12:28.95 |
+05:43:32.2 |
HIP 45252 |
14.46 |
| 2026-08-09 00:00 |
09:12:30.28 |
+05:43:25.5 |
HIP 45252 |
14.19 |
| 2026-08-09 12:00 |
09:12:31.62 |
+05:43:18.9 |
HIP 45252 |
13.93 |
| 2026-08-10 00:00 |
09:12:32.95 |
+05:43:12.2 |
HIP 45252 |
13.68 |
| 2026-08-10 12:00 |
09:12:34.28 |
+05:43:05.5 |
HIP 45252 |
13.42 |
| 2026-08-11 00:00 |
09:12:35.62 |
+05:42:58.7 |
HIP 45252 |
13.18 |
| 2026-08-11 12:00 |
09:12:36.95 |
+05:42:51.9 |
HIP 45252 |
12.94 |
| 2026-08-12 00:00 |
09:12:38.28 |
+05:42:45.1 |
HIP 45252 |
12.70 |
| 2026-08-12 12:00 |
09:12:39.61 |
+05:42:38.3 |
HIP 45252 |
12.47 |
| 2026-08-13 00:00 |
09:12:40.94 |
+05:42:31.4 |
HIP 45252 |
12.24 |
| 2026-08-13 12:00 |
09:12:42.27 |
+05:42:24.5 |
HIP 45252 |
12.02 |
| 2026-08-14 00:00 |
09:12:43.60 |
+05:42:17.5 |
HIP 45252 |
11.81 |
| 2026-08-14 12:00 |
09:12:44.92 |
+05:42:10.6 |
HIP 45252 |
11.61 |
| 2026-08-15 00:00 |
09:12:46.25 |
+05:42:03.6 |
HIP 45252 |
11.41 |
| 2026-08-15 12:00 |
09:12:47.57 |
+05:41:56.6 |
HIP 45252 |
11.22 |
| 2026-08-16 00:00 |
09:12:48.90 |
+05:41:49.5 |
HIP 45252 |
11.04 |
| 2026-08-16 12:00 |
09:12:50.22 |
+05:41:42.5 |
HIP 45252 |
10.87 |
| 2026-08-17 00:00 |
09:12:51.54 |
+05:41:35.4 |
HIP 45252 |
10.71 |
| 2026-08-17 12:00 |
09:12:52.86 |
+05:41:28.3 |
HIP 45252 |
10.56 |
| 2026-08-18 00:00 |
09:12:54.17 |
+05:41:21.1 |
HIP 45252 |
10.41 |
| 2026-08-18 12:00 |
09:12:55.49 |
+05:41:14.0 |
HIP 45252 |
10.28 |
| 2026-08-19 00:00 |
09:12:56.80 |
+05:41:06.8 |
HIP 45252 |
10.16 |