Hemera

Hemera orbits a G-class yellow star that the Hemerans call Aurea. There are five other planets visible to Hemeran telescopes, known as Bharany (a reddish inner planet), Cullina (a planet shrouded in clouds), Satlada (a white planet just beyond Hemera, likely covered in ice), Andamooka (a multi-colored gas giant), and Ruspoli (a deep blue gas giant).

Hemera's circumference is 23,656 miles, which is 95% of Earth's. Hemera's gravity is 90% of Earth's. There is one large moon, Hyperion, which has a slightly bluish, pearly gray hue and is just a bit smaller than Earth's moon; a second moon, Koios, orbits Hemera at a more distant orbit and is much smaller, having a fairly negligible effect on tides. During nights when Koios is visible in the sky, it appears to be an extremely bright star, perhaps a bit brighter than Venus in Earth's sky. Both moons are tidally locked; Hyperion orbits Hemera once every 35 days, while Koios orbits once every 127 days.

A day on Hemera is about 25 hours long. However, Hemerans have changed the length of an hour so there are still 24 hours in a day; this means that an hour is only 2.5 minutes longer than on Earth, a change that would be hardly noticeable at all.

A year on Hemera is 350 days long. Thus, the Hemeran calendar is divided into 12 months of 29 days each, with two days at the end of the year known as Novanna, which are not considered part of any month and are celebrated as a major holiday across the planet. The calendar year begins on the summer solstice as observed in Pherusa, with the following months: Arete, Bendis, Cairus, Dysis, Euporia, Faunus, Gelos, Hesperia, Iapetus, Jasion, Komos, and Leto.

Since the day is a bit longer and the year is a bit shorter, this comes out to a similar number of total hours in a year to that on Earth, meaning that ages are roughly comparable to Earth ages.

The solstices and equinoxes are celebrated as holidays across most of the planet, although the exact dates vary slightly from year to year. The summer solstice always occurs on Arete 1st in the southern hemisphere, however, and the calendar is adjusted over time, if necessary, to reflect this. However, solstices and equinoxes are usually celebrated on the first of the month, no matter where they fall precisely.

Arete 1st - Summer solstice in southern hemisphere, winter solstice in northern hemisphere

Cairus 29th or Dysis 1st - Autumnal equinox in southern hemisphere, vernal equinox in northern hemisphere

Gelos 2nd - Winter solstice in southern hemisphere, summer solstice in northern hemisphere

Jasion 1st or 2nd - Vernal equinox in southern hemisphere, autumnal equinox in northern hemisphere

The week is divided into seven days, known by the traditional names Sunday through Saturday as back on Earth. However, at the end of each month is an extra day, known as Kyrday to most. This is often used as a day to settle up accounts for the month, but is also celebrated as a day of prayer in many religions; the concept of the "eighth day" apparently originated in early Christianity back on Earth. It is usually a working day in most professions, but for teachers and professors it's usually a grading day and a day off for students. Kyrday is often used to prepare when solstice and equinox celebrations will be held the next day, and is commonly a day of baking and decorating, depending on the specific holiday in question.