Two crosses

This is Sun's sunlight cross. It marks the transitional points on the sunlight cycle in the northern hemisphere:

1. Winter solstice - the shortest day and the longest night

2. Spring equinox - the equal day and night

3. Summer solstice - the longest day and shortest night

4. Autumn equinox - the equal day and night

This is Earth's, climate, vegetation cross. It marks the transitional points of the climatic, vegetative cycle in the northern hemisphere:

Celtic calendar:

1. Imbolc- the beginning of the spring
2. Bealtaine - the beginning of the summer
3. Lughnasa - the beginning of the autumn
4. Samhain - the beginning of the winter

Serbian calendar:

1. St Sava - the beginning of the spring
2. St George - the beginning of the summer
3. St Ilija - the beginning of the autumn
4. St Mitar - the beginning of the winter

As you can see the sun cross and earth cross are out of sync. The earth cross is rotated forward by 45 degrees and the earth circle cardinal points fall right in between the sun circle cardinal points. This is because the earth climatic, vegetative cycle lags behind the solar cycle. 

Winter solstice (21st of December) is the the shortest day. So we would expect that this is also the coldest day. We would also expect that from that day on, as the days start getting longer, the days also start getting warmer. But as we all know, this is not the case. The days do get longer, but the earth continues to cool. It is only at the beginning of February that we start seeing the first signs of the earth warming up. This is why the beginning of spring is at the beginning of February (Imbolc, St Sava (14th of January, but probably a replacement for the old Imbolc which is celebrated on the 1st of February)). The actual mid point is 4th of February. Which falls right in the middle of Aquarius (21 January – 19 February).

Spring equinox (21st of March) is the moment when the day is as long as night. From that day the days are longer than nights. We would expect that this would mark the beginning of the summer. But the real heat does not start until the beginning of May. This is why the beginning of summer is at the beginning of May (Bealtaine, which is today celebrated on the 1st of May, but there are indications that it was once celebrated on the 6th of May. Here we find St George's day celebrated on the 23 of April, probably replacement for old Bealtaine). The actual mid point is 6th of May. Which falls right in the middle of Taurus (21 April – 21 May).

Summer solstice (21st of June) is the longest day of the year. We would expect that this would also be the hottest day of the year. We would also expect that from that day on, as the days get shorter, the days also get colder. But again as we all know, that is not the case. The days do get shorter, but earth continues to warm. It is only at the beginning of August that we start seeing first sings of earth cooling down. This is why the beginning of autumn is at the beginning of August (Lughnasa which is today celebrated on the 1st of August but was once probably celebrated on the, 2nd of August. Here we find St Ilija's day celebrated on the 20th of July, probably replacement for old Lughnasa). The actual mid point is 2nd of August. Which falls right in the middle of Leo (23 July – 22 August).

Autumn equinox (21st of September) is the moment when the day is as long as night. From that day the days are shorter than nights. We would expect that this would mark the beginning of the winter. But the real cold does not start until the beginning of Novermber. This is why the beginning of winter is at the beginning of November (Samhain, St Mitar (26th of October, but probably the replacement for the old Samhain which is celebrated on the 31st of October)). The actual mid point is 5th of November. Which falls right in the middle of Eagle (Scorpio) (24 October – 22 November).

This last drawing is the diagram of transformation of Sun's sunlight cycle into Earth's climatic, vegetative cycle. 

The Sun cross transitions into the Earth cross. This transition is governed by the slow accumulation and release of the heat which is transferred from the Sun to the Earth through sunlight...

Does this golden cross which symbolizes this transition of light into heat into life energy remind you of anything?

This is the never ending wheel of life...

PS: It seems that AngloSaxons had the same rotated vegetative calendar...