C/1995 Q1 (Bradfield)
| Parameter |
Value |
| Designation |
C/1995 Q1 (Bradfield) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1995-08-31T10:02:38.832000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:47Z |
| Obs used |
156 |
| NEO |
- |
| M1 |
9.600 |
| K1 |
16.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1995-10-23.0000000 |
| e |
0.99802567 |
| q (au) |
0.436387 |
| a (au) |
221.030541 |
| i (deg) |
147.394301 |
| Ω (om, deg) |
178.054729 |
| ω (w, deg) |
331.161810 |
| M (ma, deg) |
0.015771 |
Magnitude
Scatter + Global Linear
$$
M_a = (7.436 + 4.304\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.436 |
| n |
4.304 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
1.000 |
| δ90 |
1.000 |
| 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 |
| 1995-08-18 |
1995-08-30 |
-1.3532 |
+0.497 |
| 1995-09-23 |
1995-10-08 |
-3.6544 |
-0.300 |
| 1995-10-08 |
1995-10-17 |
+6.2817 |
-0.168 |
| 1995-10-17 |
1995-12-05 |
+3.3209 |
-0.463 |
| 1995-12-05 |
1995-12-28 |
-8.0172 |
+3.112 |
| 1995-12-28 |
1996-02-19 |
+15.5810 |
-5.202 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
01:23:54.66 |
+29:57:46.0 |
HIP 6573 |
10.09 |
| 2026-02-03 12:00 |
01:23:55.50 |
+29:57:38.3 |
HIP 6573 |
9.87 |
| 2026-02-04 00:00 |
01:23:56.36 |
+29:57:30.8 |
HIP 6573 |
9.65 |
| 2026-02-04 12:00 |
01:23:57.25 |
+29:57:23.4 |
HIP 6573 |
9.43 |
| 2026-02-05 00:00 |
01:23:58.15 |
+29:57:16.2 |
HIP 6573 |
9.21 |
| 2026-02-05 12:00 |
01:23:59.07 |
+29:57:09.1 |
HIP 6573 |
8.99 |
| 2026-02-06 00:00 |
01:24:00.00 |
+29:57:02.1 |
HIP 6573 |
8.76 |
| 2026-02-06 12:00 |
01:24:00.96 |
+29:56:55.3 |
HIP 6573 |
8.54 |
| 2026-02-07 00:00 |
01:24:01.94 |
+29:56:48.6 |
HIP 6573 |
8.32 |
| 2026-02-07 12:00 |
01:24:02.93 |
+29:56:42.1 |
HIP 6573 |
8.10 |
| 2026-02-08 00:00 |
01:24:03.94 |
+29:56:35.7 |
HIP 6573 |
7.87 |
| 2026-02-08 12:00 |
01:24:04.98 |
+29:56:29.4 |
HIP 6573 |
7.65 |
| 2026-02-09 00:00 |
01:24:06.03 |
+29:56:23.3 |
HIP 6573 |
7.43 |
| 2026-02-09 12:00 |
01:24:07.10 |
+29:56:17.3 |
HIP 6573 |
7.21 |
| 2026-02-10 00:00 |
01:24:08.18 |
+29:56:11.4 |
HIP 6573 |
6.99 |
| 2026-02-10 12:00 |
01:24:09.29 |
+29:56:05.7 |
HIP 6573 |
6.78 |
| 2026-02-11 00:00 |
01:24:10.41 |
+29:56:00.2 |
HIP 6573 |
6.57 |
| 2026-02-11 12:00 |
01:24:11.55 |
+29:55:54.8 |
HIP 6573 |
6.36 |
| 2026-02-12 00:00 |
01:24:12.71 |
+29:55:49.5 |
HIP 6573 |
6.15 |
| 2026-02-12 12:00 |
01:24:13.89 |
+29:55:44.4 |
HIP 6573 |
5.95 |
| 2026-02-13 00:00 |
01:24:15.08 |
+29:55:39.4 |
HIP 6573 |
5.76 |
| 2026-02-13 12:00 |
01:24:16.30 |
+29:55:34.5 |
HIP 6573 |
5.57 |
| 2026-02-14 00:00 |
01:24:17.53 |
+29:55:29.8 |
HIP 6573 |
5.40 |
| 2026-02-14 12:00 |
01:24:18.77 |
+29:55:25.3 |
HIP 6573 |
5.23 |
| 2026-02-15 00:00 |
01:24:20.04 |
+29:55:20.8 |
HIP 6573 |
5.07 |
| 2026-02-15 12:00 |
01:24:21.32 |
+29:55:16.6 |
HIP 6573 |
4.93 |
| 2026-02-16 00:00 |
01:24:22.62 |
+29:55:12.4 |
HIP 6573 |
4.80 |
| 2026-02-16 12:00 |
01:24:23.94 |
+29:55:08.5 |
HIP 6573 |
4.68 |
| 2026-02-17 00:00 |
01:24:25.27 |
+29:55:04.6 |
HIP 6573 |
4.59 |
| 2026-02-17 12:00 |
01:24:26.62 |
+29:55:00.9 |
HIP 6573 |
4.51 |
| 2026-02-18 00:00 |
01:24:27.99 |
+29:54:57.4 |
HIP 6573 |
4.46 |
| 2026-02-18 12:00 |
01:24:29.37 |
+29:54:54.0 |
HIP 6573 |
4.43 |
| 2026-02-19 00:00 |
01:24:30.77 |
+29:54:50.7 |
HIP 6573 |
4.42 |
| 2026-02-19 12:00 |
01:24:32.18 |
+29:54:47.6 |
HIP 6573 |
4.44 |
| 2026-02-20 00:00 |
01:24:33.62 |
+29:54:44.7 |
HIP 6573 |
4.48 |
| 2026-02-20 12:00 |
01:24:35.06 |
+29:54:41.8 |
HIP 6573 |
4.55 |
| 2026-02-21 00:00 |
01:24:36.53 |
+29:54:39.2 |
HIP 6573 |
4.64 |
| 2026-02-21 12:00 |
01:24:38.01 |
+29:54:36.6 |
HIP 6573 |
4.75 |
| 2026-02-22 00:00 |
01:24:39.50 |
+29:54:34.2 |
HIP 6573 |
4.89 |
| 2026-02-22 12:00 |
01:24:41.01 |
+29:54:32.0 |
HIP 6573 |
5.05 |
| 2026-02-23 00:00 |
01:24:42.54 |
+29:54:29.9 |
HIP 6573 |
5.23 |
| 2026-02-23 12:00 |
01:24:44.08 |
+29:54:28.0 |
HIP 6573 |
5.43 |
| 2026-02-24 00:00 |
01:24:45.63 |
+29:54:26.2 |
HIP 6573 |
5.64 |