Indonesia will experience interesting natural phenomena in the near future. On March 21, 2018, the Sun will be just above the equator (equator). The incident will make Indonesia during the day have no idea.
Not all of Indonesia, but such events take place in certain areas. The sun will be almost directly above the head.this results in no shadow right in the daytime."This phenomenon is called a shadowy day or a shadowless day," said Head of Public Relations Agency of National Aeronautics and Space Agency (LAPAN) Jasyanto in his written statement on Friday (16/3/2018).
LAPAN said, Indonesia experienced this two shadowy day happened this year, ie on 21 March and 23 September 2018.
This event occurs because the Earth circulates around the Sun at a distance of 150 million kilometers with a period of about 365 days.the Earth's shoreline is somewhat tapering so that the Earth sometimes moves faster and sometimes moves more slowly.
The Earth's plane is called the ecliptic plane. This field is tilted at 23.4 degrees towards Earth's equatorial plane.therefore, the Sun appears over the northern hemisphere for about half a year and is above the southern half of the rest of the world.
"Changes in the visible position of the Sun cause changes in seasons on Earth, such as four seasons in the subtropics and also wet-dry season in the territory of Indonesia," said Jasyanto.
LAPAN said on March 20, 2018 at 23:15 pm, the Sun will be directly above the equator.this event is known as the vernal equinox (vernus = spring, equus = sama, noct = night) because on that day, the duration of day and night around the world will be the same, ie 12 hours.
In the equatorial region, for example in Pontianak, West Kalimantan, the Sun will be above the head at noon of the vernal equinox so that an upright monument will appear without a shadow.
On March 21, 2018, LAPAN revealed the Sun will reach the peak / culmination at 11:50 pm.
Afterwards, the Sun will slowly fall to the point of gravity about six hours later.Similar phenomena will occur at autumnal equinox (autumn = autumn), ie on September 23, 2018.
Non-shadow day is not only happening in Pontianak or the cities passed by equator, but can occur in cities that are between 23,4 South Latitude and 23,4 North Latitude.
"The accompanying map shows shadows and culmination time in some major cities in Indonesia, for example, a shadowy day in Denpasar City on February 26 and October 16," said Jasyanto.
On a shadowless day later on March 21st, LAPAN will participate in the Shadow Nine Day Festival in Pontianak City.
The festival will run until March 23, 2018, at which time LAPAN will present mini planetarium shows, exhibits and educational lectures..
https://m.detik.com/inet/science/d-3919407/21-maret-indonesia-alami-hari-tanpa-bayangan