| Parameter |
Value |
| Designation |
C/1970 N1 (Abe) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1970-10-20T16:46:43.086720Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:19Z |
| Obs used |
271 |
| NEO |
- |
| M1 |
6.600 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1970-10-11.0000000 |
| e |
1.00003692 |
| q (au) |
1.112541 |
| a (au) |
-30136.217151 |
| i (deg) |
126.719910 |
| Ω (om, deg) |
21.701358 |
| ω (w, deg) |
96.583364 |
| M (ma, deg) |
-0.000002 |
Magnitude
Scatter + Global Linear
$$
M_a = (5.447 + 3.246\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
5.447 |
| n |
3.246 |
| gf |
0.800 |
| gb |
-0.948 |
| k |
0.999 |
| 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 |
| 1970-07-05 |
1970-10-20 |
+1.2370 |
-0.055 |
| 1970-10-20 |
1971-03-07 |
-0.0609 |
-0.277 |
| 1971-03-07 |
1971-05-25 |
+5.0362 |
-1.623 |
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 |
07:32:39.53 |
-31:20:28.5 |
HIP 36699 |
8.10 |
| 2026-07-29 12:00 |
07:32:41.10 |
-31:20:34.8 |
HIP 36699 |
7.85 |
| 2026-07-30 00:00 |
07:32:42.66 |
-31:20:41.2 |
HIP 36699 |
7.62 |
| 2026-07-30 12:00 |
07:32:44.22 |
-31:20:47.8 |
HIP 36699 |
7.39 |
| 2026-07-31 00:00 |
07:32:45.78 |
-31:20:54.5 |
HIP 36699 |
7.16 |
| 2026-07-31 12:00 |
07:32:47.33 |
-31:21:01.3 |
HIP 36699 |
6.95 |
| 2026-08-01 00:00 |
07:32:48.88 |
-31:21:08.3 |
HIP 36699 |
6.74 |
| 2026-08-01 12:00 |
07:32:50.42 |
-31:21:15.4 |
HIP 36699 |
6.55 |
| 2026-08-02 00:00 |
07:32:51.96 |
-31:21:22.6 |
HIP 36699 |
6.37 |
| 2026-08-02 12:00 |
07:32:53.50 |
-31:21:29.9 |
HIP 36699 |
6.20 |
| 2026-08-03 00:00 |
07:32:55.03 |
-31:21:37.4 |
HIP 36699 |
6.04 |
| 2026-08-03 12:00 |
07:32:56.56 |
-31:21:45.1 |
HIP 36699 |
5.90 |
| 2026-08-04 00:00 |
07:32:58.08 |
-31:21:52.8 |
HIP 36699 |
5.77 |
| 2026-08-04 12:00 |
07:32:59.60 |
-31:22:00.7 |
HIP 36699 |
5.66 |
| 2026-08-05 00:00 |
07:33:01.12 |
-31:22:08.7 |
HIP 36699 |
5.57 |
| 2026-08-05 12:00 |
07:33:02.62 |
-31:22:16.9 |
HIP 36699 |
5.49 |
| 2026-08-06 00:00 |
07:33:04.13 |
-31:22:25.1 |
HIP 36699 |
5.43 |
| 2026-08-06 12:00 |
07:33:05.63 |
-31:22:33.5 |
HIP 36699 |
5.40 |
| 2026-08-07 00:00 |
07:33:07.12 |
-31:22:42.0 |
HIP 36699 |
5.38 |
| 2026-08-07 12:00 |
07:33:08.61 |
-31:22:50.7 |
HIP 36699 |
5.39 |
| 2026-08-08 00:00 |
07:33:10.09 |
-31:22:59.5 |
HIP 36699 |
5.41 |
| 2026-08-08 12:00 |
07:33:11.57 |
-31:23:08.4 |
HIP 36699 |
5.46 |
| 2026-08-09 00:00 |
07:33:13.04 |
-31:23:17.4 |
HIP 36699 |
5.52 |
| 2026-08-09 12:00 |
07:33:14.51 |
-31:23:26.6 |
HIP 36699 |
5.60 |
| 2026-08-10 00:00 |
07:33:15.97 |
-31:23:35.9 |
HIP 36699 |
5.70 |
| 2026-08-10 12:00 |
07:33:17.42 |
-31:23:45.3 |
HIP 36699 |
5.82 |
| 2026-08-11 00:00 |
07:33:18.87 |
-31:23:54.8 |
HIP 36699 |
5.95 |
| 2026-08-11 12:00 |
07:33:20.31 |
-31:24:04.5 |
HIP 36699 |
6.10 |
| 2026-08-12 00:00 |
07:33:21.75 |
-31:24:14.2 |
HIP 36699 |
6.26 |
| 2026-08-12 12:00 |
07:33:23.18 |
-31:24:24.1 |
HIP 36699 |
6.43 |
| 2026-08-13 00:00 |
07:33:24.60 |
-31:24:34.1 |
HIP 36699 |
6.61 |
| 2026-08-13 12:00 |
07:33:26.02 |
-31:24:44.3 |
HIP 36699 |
6.81 |
| 2026-08-14 00:00 |
07:33:27.43 |
-31:24:54.5 |
HIP 36699 |
7.01 |
| 2026-08-14 12:00 |
07:33:28.83 |
-31:25:04.9 |
HIP 36699 |
7.23 |
| 2026-08-15 00:00 |
07:33:30.23 |
-31:25:15.4 |
HIP 36699 |
7.45 |
| 2026-08-15 12:00 |
07:33:31.62 |
-31:25:26.0 |
HIP 36699 |
7.67 |
| 2026-08-16 00:00 |
07:33:33.00 |
-31:25:36.7 |
HIP 36699 |
7.91 |
| 2026-08-16 12:00 |
07:33:34.37 |
-31:25:47.6 |
HIP 36699 |
8.15 |
| 2026-08-17 00:00 |
07:33:35.74 |
-31:25:58.5 |
HIP 36699 |
8.40 |
| 2026-08-17 12:00 |
07:33:37.10 |
-31:26:09.6 |
HIP 36699 |
8.65 |
| 2026-08-18 00:00 |
07:33:38.45 |
-31:26:20.8 |
HIP 36699 |
8.90 |
| 2026-08-18 12:00 |
07:33:39.79 |
-31:26:32.1 |
HIP 36699 |
9.16 |
| 2026-08-19 00:00 |
07:33:41.13 |
-31:26:43.5 |
HIP 36699 |
9.42 |