Solar term arrow

(1) The continuous rotation of the earth around the sun is called the revolution of the earth, and the direction of the revolution of the earth is from west to east;

(2) The continuous rotation of the earth around the sun is called the revolution of the earth, with a period of one year;

(3) It can be seen from the schematic diagram of the earth's revolution that when the earth is in position A, the date is 65438+February 22nd or 23rd, and the latitude of direct sunlight is tropic of Capricorn, which is the winter solstice in the northern hemisphere; When the earth is in position B, the date is March 20th or 2 1, and the latitude line with direct sunlight is the equator, that is, the vernal equinox in the northern hemisphere. When the earth is in position C, the date is June 2 1 or 22, and the sun is directly on the tropic of cancer, which is the summer solstice in the northern hemisphere; When the earth is in position D, the date is September 22nd or 23rd, and the latitude of direct sunlight is the equator, which is the autumn equinox in the northern hemisphere.

(4) It can be seen from the schematic diagram of the earth's revolution that when the earth is in position C, the sun is facing the Tropic of Cancer and is located at the northernmost point of the direct point. At this time, the northern hemisphere has the longest day and the shortest night.

So the answer is: (1)

(2) one year; (3) winter solstice; Vernal equinox; Summer solstice; Vernal equinox; (4) The days are long and the nights are short.