User:Thedukeofnuke/Astronomy
This page is intended as a reference to the solar system in which Akana exists. Many of these details are not known accurately or at all by pre-modern Akanaran peoples, but the appearance and cyclic behaviour of the Sun and Moon in particular are important to humans in all periods.
The Sun
Akana's sun is a yellow star similar to, but marginally larger and brighter than, our own.
| physical characteristics | ||
| luminosity | +4.81 absolute | 1.041× Sol |
| mass | 2.022×1030 kg | 1.017× Sol |
| diameter | 1,404,507 km | 1.008× Sol |
From Akana the sun appears as bright as our own, though marginally smaller: it varies between 0.540° and 0.505° of arc in apparent diameter.
Akana
Akana itself is a terrestrial planet very similar to the Earth, marginally less massive but with almost identical composition and surface gravity. Its year is slightly longer, but its day is shorter, and it has a slightly smaller axial tilt.
| physical characteristics | ||
| mass | 5.883×1024 kg | 0.985× Earth |
| diameter | 12,679 km | 0.995× Earth |
| density | 5.515 g/cm3 | 1.000× Earth |
| surface gravity | 9.772 m/s2 | 0.995 g |
| orbital characteristics | ||
| semi-major axis | 152,891,146 km | 1.022 AU |
| eccentricity | 0.0093 | 0.557× Earth |
| perihelion | 147,769,293 km | 0.988 AU |
| aphelion | 158,013,000 km | 1.056 AU |
| year | 32,252,877 s 384.1 synodic days |
1.022× Earth |
| rotational characteristics | ||
| synodic day | 83,970 s | 23 hr 19 min 30 s |
| rotational period | 83,752 s | 23 hr 15 min 52 s |
| axial tilt | 21.52° | 0.918× Earth |
The Moon
Akana has one moon, significantly larger than ours but somewhat more distant. It may be tidally locked to Akana, but this is not definitely known.
| physical characteristics | ||
| mass | 1.338×1023 kg | 1.821× Luna |
| diameter | 4,391 km | 1.254× Luna |
| density | 3.020 g/cm3 | 0.902× Luna |
| surface gravity | 1.853 m/s2 | 0.189 g 1.142× Luna |
| orbital characteristics | ||
| semi-major axis | 484,357 km | 1.260× Luna |
| eccentricity | 0.0429 | 0.781× Luna |
| perigee | 463,578 km | |
| apogee | 505,136 km | |
| synodic month | 3,775,291.2 s 44.96 synodic days |
|
| orbital period | 3,379,689 s 40.249 synodic days |
|
The moon appears very similar in brightness to ours, though marginally smaller: it varies between 0.543° and 0.498° of arc in apparent diameter.
Due to the moon's size and orbital parameters, tides on Akana are about 15% stronger than ours. and total eclipses are somewhat rarer (they are more usually partial or annular).