C/1942 X1 (Whipple-Fedtke-Tevzadze)
Metadata
| Parameter | Value |
|---|---|
| Designation | C/1942 X1 (Whipple-Fedtke-Tevzadze) |
| Type | C |
| Perihelion (tp_cal, UTC) | 1943-02-06T17:18:23.040000Z |
| Orbit solution date (soln_date, UTC) | - |
| Obs used | 166 |
| NEO | - |
| M1 | - |
| K1 | - |
| PC | - |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 1943-02-05.0000000 |
| e | 0.99219600 |
| q (au) | 1.353647 |
| a (au) | 173.455536 |
| i (deg) | 19.712700 |
| Ω (om, deg) | 100.799000 |
| ω (w, deg) | 39.843200 |
| M (ma, deg) | -0.000743 |
Magnitude
Scatter + Global Linear
$$ M_a = (3.857 + 3.863\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 3.857 |
| n | 3.863 |
| gf | 1.000 |
| gb | -0.500 |
| k | 1.000 |
| δ90 | 10.000 |
| 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 |
|---|---|---|---|
| 1942-12-15 | 1943-02-06 | +38.1961 | -4.915 |
| 1943-02-06 | 1943-04-13 | +2.8278 | -0.764 |
| 1943-04-13 | 1943-06-05 | -2.7997 | +0.823 |
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 | 20:52:24.80 | -27:06:46.2 | HIP 102954 | 13.86 |
| 2026-02-03 12:00 | 20:52:26.13 | -27:06:41.6 | HIP 102954 | 14.15 |
| 2026-02-04 00:00 | 20:52:27.45 | -27:06:36.9 | HIP 102978 | 14.27 |
| 2026-02-04 12:00 | 20:52:28.78 | -27:06:32.3 | HIP 102978 | 14.39 |
| 2026-02-05 00:00 | 20:52:30.10 | -27:06:27.7 | HIP 102978 | 14.51 |
| 2026-02-05 12:00 | 20:52:31.42 | -27:06:23.1 | HIP 102978 | 14.64 |
| 2026-02-06 00:00 | 20:52:32.74 | -27:06:18.6 | HIP 102978 | 14.77 |
| 2026-02-06 12:00 | 20:52:34.06 | -27:06:14.1 | HIP 102978 | 14.91 |
| 2026-02-07 00:00 | 20:52:35.38 | -27:06:09.6 | HIP 102978 | 15.05 |
| 2026-02-07 12:00 | 20:52:36.69 | -27:06:05.2 | HIP 102978 | 15.20 |
| 2026-02-08 00:00 | 20:52:38.01 | -27:06:00.7 | HIP 102978 | 15.35 |
| 2026-02-08 12:00 | 20:52:39.32 | -27:05:56.4 | HIP 102978 | 15.51 |
| 2026-02-09 00:00 | 20:52:40.63 | -27:05:52.0 | HIP 102978 | 15.67 |
| 2026-02-09 12:00 | 20:52:41.94 | -27:05:47.7 | HIP 102978 | 15.84 |
| 2026-02-10 00:00 | 20:52:43.25 | -27:05:43.4 | HIP 102978 | 16.01 |
| 2026-02-10 12:00 | 20:52:44.56 | -27:05:39.1 | HIP 102978 | 16.18 |
| 2026-02-11 00:00 | 20:52:45.86 | -27:05:34.9 | HIP 102978 | 16.36 |
| 2026-02-11 12:00 | 20:52:47.16 | -27:05:30.7 | HIP 102978 | 16.54 |
| 2026-02-12 00:00 | 20:52:48.46 | -27:05:26.5 | HIP 102978 | 16.72 |
| 2026-02-12 12:00 | 20:52:49.76 | -27:05:22.4 | HIP 102978 | 16.91 |
| 2026-02-13 00:00 | 20:52:51.06 | -27:05:18.3 | HIP 102978 | 17.10 |
| 2026-02-13 12:00 | 20:52:52.35 | -27:05:14.3 | HIP 102978 | 17.29 |
| 2026-02-14 00:00 | 20:52:53.64 | -27:05:10.2 | HIP 102978 | 17.49 |
| 2026-02-14 12:00 | 20:52:54.93 | -27:05:06.3 | HIP 102978 | 17.69 |
| 2026-02-15 00:00 | 20:52:56.21 | -27:05:02.3 | HIP 102978 | 17.89 |
| 2026-02-15 12:00 | 20:52:57.49 | -27:04:58.4 | HIP 102978 | 18.09 |
| 2026-02-16 00:00 | 20:52:58.77 | -27:04:54.5 | HIP 102978 | 18.30 |
| 2026-02-16 12:00 | 20:53:00.04 | -27:04:50.7 | HIP 102978 | 18.50 |
| 2026-02-17 00:00 | 20:53:01.32 | -27:04:46.8 | HIP 102978 | 18.71 |
| 2026-02-17 12:00 | 20:53:02.58 | -27:04:43.1 | HIP 102978 | 18.92 |
| 2026-02-18 00:00 | 20:53:03.85 | -27:04:39.3 | HIP 102978 | 19.14 |
| 2026-02-18 12:00 | 20:53:05.11 | -27:04:35.6 | HIP 102978 | 19.35 |
| 2026-02-19 00:00 | 20:53:06.37 | -27:04:32.0 | HIP 102978 | 19.57 |
| 2026-02-19 12:00 | 20:53:07.62 | -27:04:28.3 | HIP 102978 | 19.78 |
| 2026-02-20 00:00 | 20:53:08.87 | -27:04:24.8 | HIP 102978 | 20.00 |
| 2026-02-20 12:00 | 20:53:10.12 | -27:04:21.2 | HIP 102978 | 20.22 |
| 2026-02-21 00:00 | 20:53:11.36 | -27:04:17.7 | HIP 102978 | 20.44 |
| 2026-02-21 12:00 | 20:53:12.60 | -27:04:14.2 | HIP 102978 | 20.66 |
| 2026-02-22 00:00 | 20:53:13.83 | -27:04:10.8 | HIP 102978 | 20.89 |
| 2026-02-22 12:00 | 20:53:15.06 | -27:04:07.4 | HIP 102978 | 21.11 |
| 2026-02-23 00:00 | 20:53:16.29 | -27:04:04.1 | HIP 102978 | 21.33 |
| 2026-02-23 12:00 | 20:53:17.51 | -27:04:00.7 | HIP 102978 | 21.56 |
| 2026-02-24 00:00 | 20:53:18.73 | -27:03:57.5 | HIP 102978 | 21.78 |