[Updated March 20, 2016 at 4:23 p.m.] The spring equinox in 2016 has already arrived. This Sunday, March 20, at 5:30 am, the winter ended, the astronomical sense, and we entered what we commonly call the summer. The date of the first day of spring 2016 also happens especially early in the calendar this year. It’s 120 years that spring had not been greater, this time chasing the winter so it lasts one day less than usual. The explanation is relatively simple but requires some explanation.
First, the spring equinox is a time of year when the sun crosses the equatorial plane of the earth. The star was then at the zenith of Ecuador. The best known of this astronomical phenomenon consequence is that the days and nights have the same approximate length everywhere on Earth , in both hemispheres, south and north. For our part, the days get longer and we are halfway between the short days of December and the long days of June. The equinox occurs twice a year: between 19 and 21 March (vernal or spring equinox) and between 22 and 23 September (autumnal equinox)
VIDEO IN. – a few days before the spring equinox in 2016, the cold was still present in some areas
in 2016, spring has officially started March 20 a date and even time ( 5:30 ET 11 seconds precisely) that spring 2016 one of the earliest history of the country. How to explain that the first day of spring falls so early in the year? Note that the exact time of the equinox – that is to say the time the equatorial plane and the trajectory of the Earth coincide – is calculated for each year by astronomers and mathematicians. A calculation made necessary by the gap between our calendar and time system and the movements of the stars. First, the Earth’s orbit is not perfectly circular, so that in relation to its position on this orbit, the Earth may be more or less close to the sun (between 147 million kilometers and minimum up to 152 million kilometers). That inevitably makes the durations of each very irregular season
Another explanation. Earth does not exactly 365 days to circle the sun. In this our Gregorian calendar, established in the sixteenth century, is far too simplistic. It is indeed 365.2422 days exactly (365 days, 5 hours and 46 minutes) so that we have come full circle to the star! We are already obliged to add from time to time on February 29 (in leap years) to correct in part (and only partially) offset this. So the man has not quite managed to adapt his schedule to the law of the seasons. and the addition of 29 February 2016 in the calendar would have postponed the date spring day if the latter was not “advanced” to 20 March.
When the establishment of the Julian calendar by Caesar in 45 BC, the spring equinox was set for March 25, based on inaccurate observations of the time. But the absence of 29 February in this ancient calendar eventually move that date up to March 11 in the sixteenth century … It is only when establishing the Gregorian calendar (the one we use today) in 1582, approaching a date of March 21 has been selected.
on the astronomical point of view, spring begins at the vernal equinox, which may take place between 19 and March 21. In the coming years, it will be mainly on 20 March. This was also the case in 2015, the spring equinox was then held on 20 March, 22:45 9 seconds Universal Time (or 11:45 p.m. ET nine seconds at the Paris time). It was not until 2044 years for the equinox occurs on 19 March. As for the summer solstice, it will be for the next 21 June 2016. What makes the spring lasts about three months.
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