| Parameter |
Value |
| Designation |
C/1980 E1 (Bowell) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1982-03-12T06:53:06.725760Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:29Z |
| Obs used |
187 |
| NEO |
- |
| M1 |
5.800 |
| K1 |
7.250 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1982-01-03.0000000 |
| e |
1.05773287 |
| q (au) |
3.363940 |
| a (au) |
-58.267328 |
| i (deg) |
1.661742 |
| Ω (om, deg) |
114.557492 |
| ω (w, deg) |
135.083294 |
| M (ma, deg) |
-0.151323 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.115 + 2.337\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.115 |
| n |
2.337 |
| gf |
0.934 |
| gb |
-0.841 |
| k |
0.998 |
| 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 |
| 1980-02-11 |
1981-05-06 |
+4.8533 |
-3.657 |
| 1981-05-06 |
1982-03-05 |
-7.7973 |
+4.010 |
| 1982-03-15 |
1982-10-11 |
+4.0331 |
-2.092 |
| 1982-10-11 |
1986-12-02 |
-0.1566 |
+0.588 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
02:30:09.69 |
+13:07:17.2 |
HIP 11691 |
20.69 |
| 2026-06-01 12:00 |
02:30:11.05 |
+13:07:23.4 |
HIP 11691 |
20.45 |
| 2026-06-02 00:00 |
02:30:12.39 |
+13:07:29.6 |
HIP 11691 |
20.22 |
| 2026-06-02 12:00 |
02:30:13.73 |
+13:07:35.7 |
HIP 11691 |
19.99 |
| 2026-06-03 00:00 |
02:30:15.07 |
+13:07:41.9 |
HIP 11691 |
19.76 |
| 2026-06-03 12:00 |
02:30:16.39 |
+13:07:48.0 |
HIP 11691 |
19.54 |
| 2026-06-04 00:00 |
02:30:17.71 |
+13:07:54.0 |
HIP 11691 |
19.32 |
| 2026-06-04 12:00 |
02:30:19.03 |
+13:08:00.0 |
HIP 11691 |
19.11 |
| 2026-06-05 00:00 |
02:30:20.33 |
+13:08:06.0 |
HIP 11691 |
18.90 |
| 2026-06-05 12:00 |
02:30:21.63 |
+13:08:11.9 |
HIP 11691 |
18.70 |
| 2026-06-06 00:00 |
02:30:22.93 |
+13:08:17.8 |
HIP 11691 |
18.50 |
| 2026-06-06 12:00 |
02:30:24.21 |
+13:08:23.7 |
HIP 11691 |
18.31 |
| 2026-06-07 00:00 |
02:30:25.49 |
+13:08:29.5 |
HIP 11691 |
18.13 |
| 2026-06-07 12:00 |
02:30:26.76 |
+13:08:35.3 |
HIP 11691 |
17.94 |
| 2026-06-08 00:00 |
02:30:28.03 |
+13:08:41.0 |
HIP 11691 |
17.77 |
| 2026-06-08 12:00 |
02:30:29.28 |
+13:08:46.7 |
HIP 11691 |
17.59 |
| 2026-06-09 00:00 |
02:30:30.53 |
+13:08:52.3 |
HIP 11691 |
17.43 |
| 2026-06-09 12:00 |
02:30:31.77 |
+13:08:57.9 |
HIP 11691 |
17.27 |
| 2026-06-10 00:00 |
02:30:33.00 |
+13:09:03.5 |
HIP 11691 |
17.11 |
| 2026-06-10 12:00 |
02:30:34.23 |
+13:09:09.0 |
HIP 11691 |
16.96 |
| 2026-06-11 00:00 |
02:30:35.45 |
+13:09:14.5 |
HIP 11691 |
16.82 |
| 2026-06-11 12:00 |
02:30:36.66 |
+13:09:19.9 |
HIP 11691 |
16.68 |
| 2026-06-12 00:00 |
02:30:37.86 |
+13:09:25.3 |
HIP 11691 |
16.54 |
| 2026-06-12 12:00 |
02:30:39.05 |
+13:09:30.7 |
HIP 11691 |
16.42 |
| 2026-06-13 00:00 |
02:30:40.24 |
+13:09:36.0 |
HIP 11691 |
16.29 |
| 2026-06-13 12:00 |
02:30:41.42 |
+13:09:41.2 |
HIP 11691 |
16.18 |
| 2026-06-14 00:00 |
02:30:42.58 |
+13:09:46.4 |
HIP 11691 |
16.07 |
| 2026-06-14 12:00 |
02:30:43.74 |
+13:09:51.6 |
HIP 11691 |
15.96 |
| 2026-06-15 00:00 |
02:30:44.90 |
+13:09:56.7 |
HIP 11691 |
15.86 |
| 2026-06-15 12:00 |
02:30:46.04 |
+13:10:01.8 |
HIP 11691 |
15.77 |
| 2026-06-16 00:00 |
02:30:47.17 |
+13:10:06.8 |
HIP 11691 |
15.68 |
| 2026-06-16 12:00 |
02:30:48.30 |
+13:10:11.8 |
HIP 11691 |
15.59 |
| 2026-06-17 00:00 |
02:30:49.41 |
+13:10:16.7 |
HIP 11691 |
15.52 |
| 2026-06-17 12:00 |
02:30:50.52 |
+13:10:21.6 |
HIP 11691 |
15.45 |
| 2026-06-18 00:00 |
02:30:51.62 |
+13:10:26.5 |
HIP 11691 |
15.38 |
| 2026-06-18 12:00 |
02:30:52.71 |
+13:10:31.2 |
HIP 11691 |
15.32 |
| 2026-06-19 00:00 |
02:30:53.79 |
+13:10:36.0 |
HIP 11691 |
15.26 |
| 2026-06-19 12:00 |
02:30:54.86 |
+13:10:40.7 |
HIP 11691 |
15.21 |
| 2026-06-20 00:00 |
02:30:55.92 |
+13:10:45.3 |
HIP 11691 |
15.17 |
| 2026-06-20 12:00 |
02:30:56.97 |
+13:10:49.9 |
HIP 11691 |
15.13 |
| 2026-06-21 00:00 |
02:30:58.02 |
+13:10:54.4 |
HIP 11691 |
15.09 |
| 2026-06-21 12:00 |
02:30:59.05 |
+13:10:58.9 |
HIP 11691 |
15.06 |
| 2026-06-22 00:00 |
02:31:00.07 |
+13:11:03.4 |
HIP 11691 |
15.04 |