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Thank you for reading the news on the planned date of spring moderation and start now with the details.
Jeddah – Gulf 365 Monitoring – Riyadh:
The president of the Jeddah Astronomical Society, the engineer Majid Abu Zahra, explained that the spring equinox was held on Thursday, March 21, 2019 at 12:58 GMT (9:58 pm Wednesday), the first day of spring being astronomical .
Abu Zahra said that the spring equinox represents a point of Earth's orbit around the sun, but also a sign of when the sun "seems" to cross the celestial equator, moving from the south half to the north half of the celestial dome.
He pointed out that on that day, the sun is vertical at the equator and that heat and light are evenly distributed over the hemispheres, while areas north and south of the tropical region are inclined and fall from 90 degrees on the equator to zero in the poles. The axis of the Earth is 23.5 degrees.
"So, in general, the duration of the day is supposed to be 12 hours and the night of 12 hours, but that does not happen exactly for two reasons: first, the sun is a circular disk, not a bright spot like the distant stars.
Most calendars connect the sunrise to the first contact between its edge and the horizon. The sun goes down when the last edge of the solar disk touches the western horizon, which itself gives about 3 minutes of additional daylight at mid-latitudes.
"The second reason is refraction.The Earth's atmosphere functions like a lens or a leaf, it raises the sun by 0.5 degrees from its actual geometrical position as the sun approaches.
It is a coincidence that the diameter of the angular sun is about 0.5 degrees. This means that when we see the sun on the horizon fall below the horizon, this leads to the progression of the sunrise, delaying the sunset, adds about 6 minutes of daylight to mid-latitudes; Day in moderation ".
He pointed out that it can be noted that astronomical calendars do not usually give rise or sunset to the second. This atmospheric refraction is somewhat variable: it depends on the low temperature, the high humidity and the barometric pressure, all of which increase the atmospheric refraction.
He said that the sky observatory on the day of the spring equinox will notice that the sun rises from the point is original and retreats to the original western point, and then that he will notice that dawn is early and the sun goes down late. By observing each day the path of the sun visible in the dome of the sky, he will notice that he is moving to the north.
He pointed out that after weeks of spring, the equinox will notice that the sun rises from the northeast, as the Earth has changed position in orbit around the sun;
The spring season will last 3 months, 17 hours and 56 minutes until the summer solstice on June 21st.
Here are the details of the current timing of the spring equinox for today. We hope to have been able to provide you with all the necessary details and information. To follow all our news, you can subscribe to the alert system or to one of our different systems to provide you with all the news.
It should also be noted that the original article was published and is in the newspaper. The Gulf 365 editorial team confirmed that it may have been modified and that it had been fully transferred or cited. You can read and follow the news from this source.
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