| Parameter |
Value |
| Designation |
C/1977 V1 (Tsuchinshan) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1977-07-24T20:21:58.737600Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:27Z |
| Obs used |
69 |
| NEO |
- |
| M1 |
6.100 |
| K1 |
10.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1978-01-05.0000000 |
| e |
0.99939607 |
| q (au) |
3.603189 |
| a (au) |
5966.223621 |
| i (deg) |
168.548706 |
| Ω (om, deg) |
5.287760 |
| ω (w, deg) |
318.178421 |
| M (ma, deg) |
0.000351 |
Magnitude
Scatter + Global Linear
$$
M_a = (5.775 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
5.775 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.699 |
| k |
0.802 |
| δ90 |
9.864 |
| 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 |
| 1977-11-08 |
1978-10-31 |
+17.3547 |
-10.143 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
16:53:11.60 |
-11:50:22.3 |
HIP 82638 |
7.67 |
| 2026-03-26 12:00 |
16:53:10.96 |
-11:50:16.9 |
HIP 82638 |
7.72 |
| 2026-03-27 00:00 |
16:53:10.30 |
-11:50:11.6 |
HIP 82638 |
7.77 |
| 2026-03-27 12:00 |
16:53:09.63 |
-11:50:06.2 |
HIP 82638 |
7.84 |
| 2026-03-28 00:00 |
16:53:08.95 |
-11:50:00.8 |
HIP 82638 |
7.91 |
| 2026-03-28 12:00 |
16:53:08.26 |
-11:49:55.3 |
HIP 82638 |
7.98 |
| 2026-03-29 00:00 |
16:53:07.55 |
-11:49:49.9 |
HIP 82638 |
8.06 |
| 2026-03-29 12:00 |
16:53:06.83 |
-11:49:44.5 |
HIP 82638 |
8.15 |
| 2026-03-30 00:00 |
16:53:06.09 |
-11:49:39.1 |
HIP 82638 |
8.25 |
| 2026-03-30 12:00 |
16:53:05.34 |
-11:49:33.6 |
HIP 82638 |
8.35 |
| 2026-03-31 00:00 |
16:53:04.58 |
-11:49:28.2 |
HIP 82638 |
8.46 |
| 2026-03-31 12:00 |
16:53:03.80 |
-11:49:22.7 |
HIP 82638 |
8.57 |
| 2026-04-01 00:00 |
16:53:03.02 |
-11:49:17.3 |
HIP 82638 |
8.69 |
| 2026-04-01 12:00 |
16:53:02.21 |
-11:49:11.8 |
HIP 82638 |
8.82 |
| 2026-04-02 00:00 |
16:53:01.40 |
-11:49:06.3 |
HIP 82638 |
8.95 |
| 2026-04-02 12:00 |
16:53:00.57 |
-11:49:00.9 |
HIP 82602 |
9.01 |
| 2026-04-03 00:00 |
16:52:59.73 |
-11:48:55.4 |
HIP 82602 |
8.98 |
| 2026-04-03 12:00 |
16:52:58.88 |
-11:48:49.9 |
HIP 82602 |
8.96 |
| 2026-04-04 00:00 |
16:52:58.01 |
-11:48:44.4 |
HIP 82602 |
8.94 |
| 2026-04-04 12:00 |
16:52:57.13 |
-11:48:38.9 |
HIP 82602 |
8.93 |
| 2026-04-05 00:00 |
16:52:56.24 |
-11:48:33.4 |
HIP 82602 |
8.93 |
| 2026-04-05 12:00 |
16:52:55.33 |
-11:48:27.9 |
HIP 82602 |
8.94 |
| 2026-04-06 00:00 |
16:52:54.42 |
-11:48:22.5 |
HIP 82602 |
8.95 |
| 2026-04-06 12:00 |
16:52:53.49 |
-11:48:17.0 |
HIP 82602 |
8.98 |
| 2026-04-07 00:00 |
16:52:52.54 |
-11:48:11.5 |
HIP 82602 |
9.01 |
| 2026-04-07 12:00 |
16:52:51.59 |
-11:48:06.0 |
HIP 82602 |
9.05 |
| 2026-04-08 00:00 |
16:52:50.62 |
-11:48:00.5 |
HIP 82602 |
9.09 |
| 2026-04-08 12:00 |
16:52:49.64 |
-11:47:55.0 |
HIP 82602 |
9.15 |
| 2026-04-09 00:00 |
16:52:48.65 |
-11:47:49.5 |
HIP 82602 |
9.21 |
| 2026-04-09 12:00 |
16:52:47.64 |
-11:47:44.0 |
HIP 82602 |
9.28 |
| 2026-04-10 00:00 |
16:52:46.63 |
-11:47:38.5 |
HIP 82602 |
9.37 |
| 2026-04-10 12:00 |
16:52:45.60 |
-11:47:33.0 |
HIP 82602 |
9.46 |
| 2026-04-11 00:00 |
16:52:44.56 |
-11:47:27.5 |
HIP 82602 |
9.56 |
| 2026-04-11 12:00 |
16:52:43.51 |
-11:47:22.0 |
HIP 82602 |
9.66 |
| 2026-04-12 00:00 |
16:52:42.44 |
-11:47:16.6 |
HIP 82602 |
9.78 |
| 2026-04-12 12:00 |
16:52:41.37 |
-11:47:11.1 |
HIP 82602 |
9.90 |
| 2026-04-13 00:00 |
16:52:40.28 |
-11:47:05.6 |
HIP 82602 |
10.04 |
| 2026-04-13 12:00 |
16:52:39.18 |
-11:47:00.1 |
HIP 82602 |
10.18 |
| 2026-04-14 00:00 |
16:52:38.07 |
-11:46:54.7 |
HIP 82602 |
10.33 |
| 2026-04-14 12:00 |
16:52:36.95 |
-11:46:49.2 |
HIP 82602 |
10.48 |
| 2026-04-15 00:00 |
16:52:35.81 |
-11:46:43.8 |
HIP 82602 |
10.65 |
| 2026-04-15 12:00 |
16:52:34.67 |
-11:46:38.3 |
HIP 82602 |
10.82 |
| 2026-04-16 00:00 |
16:52:33.51 |
-11:46:32.9 |
HIP 82602 |
11.00 |