Equinox on Planet Earth - UNIVERSE (March 20 - 2019)
Welcome to an equinox on
planet Earth. (Today) is the first day of spring in our fair planet’s northern
hemisphere, fall in the southern hemisphere, with day and night nearly equal
around the globe. At an equinox Earth’s terminator,
the dividing line between day and night, connects the planet’s north and south
poles as seen at the start of this remarkable time-lapse video compressing
an entire year into twelve seconds. To make it, the Meteosat satellite
recorded these
infrared images every day at the same local time from a geosynchronous
orbit. The video actually starts at the September 2010 equinox with the
terminator aligned vertically. As the Earth revolves around
the Sun, the terminator tilts
to provide less daily sunlight to the northern hemisphere, reaching the
solstice and northern hemisphere winter at the maximum tilt. As the year
continues, the terminator tilts back again and March 2011 equinox arrives
halfway through the video. Then the terminator swings past vertical the other
way, reaching the the June 2011 solstice and the beginning of northern
summer. The video ends as the September equinox returns.
No comments:
Post a Comment