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Majid Abu Zahra, president of the Jeddah Astronomical Society, said: "The spring equinox takes place on Thursday, March 21, 2019 at 12:58 pm (midnight) in Saudi Arabia (9:58 pm Wednesday, GMT), the first day of spring.
He explained that the spring equinox represents a point of Earth's orbit around the sun, which is also a sign of the moment the sun "crosses" apparently the celestial equator, moving from the southern half to the northern 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.
"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 point like distant stars Most calendars connect the sunrise to the first contact between its edge and the east 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 is the refraction of the air: the earth's atmosphere acts as a lens or a leaf, the sun rising to 0.5 degree from its actual geometric position on the approach to the air. ;horizon. 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.
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"Astrology of Jeddah": the spring equinox and the first days of spring astronomy .. thursday
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2019-03-18
Majid Abu Zahra, president of the Jeddah Astronomical Society, said: "The spring equinox takes place on Thursday, March 21, 2019 at 12:58 pm (midnight) in Saudi Arabia (9:58 pm Wednesday, GMT), the first day of spring.
He explained that the spring equinox represents a point of Earth's orbit around the sun, which is also a sign of the moment the sun "crosses" apparently the celestial equator, moving from the southern half to the northern 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.
"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 point like distant stars Most calendars connect the sunrise to the first contact between its edge and the east 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 is the refraction of the air: the earth's atmosphere acts as a lens or a leaf, the sun rising to 0.5 degree from its actual geometric position on the approach to the air. ;horizon. 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.
Fixing area
March 18, 2019 – 11 Rajab 1440
The time now is 09:15 PM
Majid Abu Zahra, president of the Jeddah Astronomical Society, said: "The spring equinox takes place on Thursday, March 21, 2019 at 12:58 pm (midnight) in Saudi Arabia (9:58 pm Wednesday, GMT), the first day of spring.
He explained that the spring equinox represents a point of Earth's orbit around the sun, which is also a sign of the moment the sun "crosses" apparently the celestial equator, moving from the southern half to the northern 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.
"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 point like distant stars Most calendars connect the sunrise to the first contact between its edge and the east 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 is the refraction of the air: the earth's atmosphere acts as a lens or a leaf, the sun rising to 0.5 degree from its actual geometric position on the approach to the air. ;horizon. 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.
Fixing area
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