Through the Earth’s journey across the Solar, solstices come round twice a yr, on the factors in Earth’s orbit the place this tilt is most pronounced. The summer time solstice begins round June 21 whereas the December solstice arrives on December 21. Solstices additionally mark the change of seasons all year long. The primary day of the Summer time Solstice marks the day when the Solar is immediately over the Tropic of Most cancers which is positioned at 23.5° latitude North. June 21 can be the longest day of the yr, however why is it so?
The science behind Summer time Solstice
Firstly, Solstice means ‘solar stands nonetheless’ in Latin. In accordance with NASA, solstices and equinoxes function indicators of the seasons, ensuing from the Earth’s axial tilt of 23.5 levels with respect to its orbital path across the solar. Because of the tilt, totally different elements of the Earth obtain totally different quantities of daylight, relying on the time of yr. The Northern Hemisphere is tilted towards the solar throughout Summer time Solstice, which means it receives the total photo voltaic glare on as of late. Furthermore, the farther you go within the Northern Hemisphere, the extra hours of daylight you may see. Subsequently, it makes June 21, which is the start of the Summer time Solstice, the longest day of the yr.
Nonetheless, the Summer time Solstice does not at all times happen on the identical day yearly. It is because whereas the Gregorian Calender has 12 months, Earth takes about 365.25 days in actuality. That’s the reason yet one more day is added each 4 years, which is named the intercalary year.
Why is Earth tilted?
NASA states that a very long time in the past, a large object referred to as Theia, concerning the dimension of Mars, collided with our planet, knocking it off its axis a bit. So as an alternative of rotating straight up and down, Earth leans a bit off its axis. Furthermore, this collision additionally resulted within the formation of the Moon, which is Earth’s solely pure satellite tv for pc.
