Solstices and equinoxes
In 2022, the December solstice (winter for the Northern Hemisphere, summer time for the Southern Hemisphere) will happen at 21:48 UTC on December 21.
This solstice marks the sun’s southernmost level in our sky.
And the truth that Earth’s Northern and Southern Hemispheres have their summers and winters at reverse instances of 12 months gives a clue to the rationale for Earth’s seasons. That purpose is Earth’s 23 1/2-degree tilt on its axis. It’s pure to suppose our world’s seasons consequence from our altering distance from the sun. However we’re nearer to the sun in northern winter, and farther from the sun in northern summer time. So it’s not Earth’s distance from the sun that causes your seasons to vary. As a substitute, on our tilted world, the angle of daylight hanging your location shifts in a yearly cycle, as we journey across the sun.
The pictures and video on this web page – from NASA – present Earth’s solstices and equinoxes from space. They might help you visualize why our seasons unfold as they do, constantly, all through annually.
All you need to know: June solstice 2023
Viewing the solstices and equinoxes from space
EUMETSAT‘s Meteosat-9 (a climate satellite) captured the 4 views above of Earth from geosynchronous orbit in 2010 and 2011. A satellite in geosynchronous orbit stays over the identical level on Earth on a regular basis. And the photographs above present how daylight fell on the Earth on December 21, 2010 (higher left), March 20, 2011 (higher proper), June 21, 2011 (decrease left), and September 20, 2011 (decrease proper). Additionally, every picture was taken at 6:12 a.m. native time.
Round 6 a.m. native time every day, the sun, Earth, and any geosynchronous satellite kind a proper angle. Thus, affording straight-down view of Earth’s terminator line, that’s, the road between our world’s day and evening sides. The form of this line between evening and day varies with the seasons. And leads to completely different lengths of days and differing quantities of warming sunshine.
Whereas the road is definitely a curve as a result of the Earth is spherical, satellite photos present it in two dimensions solely.
On March 20 and September 20, the terminator is a straight north-south line, and the sun sits immediately above the equator. Then on December 21, the sun resides immediately over the Tropic of Capricorn when considered from the bottom, and daylight spreads over extra of the Southern Hemisphere. Subsequent on June 21, the sun sits above the Tropic of Cancer, spreading extra daylight within the north.
Backside line: A video from NASA reveals how daylight falls on Earth’s floor through the solstices and equinoxes, as seen by the climate satellite Meteosat-9 in 2010 and 2011.
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