The termination line coincides with the meridian and the geographical coordinates of the direct point of the sun.

(1) The termination line coincides with the meridian, which is the vernal equinox or autumnal equinox, and the sun shines directly on the equator; According to the meridian position of 180, we can get that the direct meridian of the sun is150 e. At this time, the morning twilight circle coincides with the warp coil, and the local time of the morning line is 6 o'clock. According to "the east is early and the west is late, and the east increases and the west decreases", the meridian longitude coincident with the morning line is 60 e.

(2) According to the above problems, the local time of 60 E is 6 o'clock, and according to "East is early and west is late, east is increasing and west is decreasing", Beijing time is 10; There are two date lines, one is the longitude at 0 o'clock and the other is the longitude at 180. At the same time as the date in Beijing, it is from West Zone 2 to East Zone 12.

(3) The formula for calculating the noon sun height is H = 90°- the latitude difference between them. On that day, the noon sun altitude angle (31n) in Shanghai was 59; On that day, the global midday sun height distribution law is decreasing from the equator to the north and south sides.

(4) The formula for calculating the noon sun height is H = 90°- the latitude difference between them. If the noonday angle of the sun in China is 70, the latitude is 20 n. 。

(5) If the Beijing time at sunrise in a certain place in China is 5: 44, the longitude of the place is124 e according to "East is early and west is late, East is added and West is reduced"; ; On that day, the Beijing time at sunset was 17: 44.

(6) If extreme sunlight appears near the North Pole after that day, it can be determined that the solar term of this day is the vernal equinox.

So the answer is: (1) (0,150 e); ); 60 E。

(2) at10; West 2.

(3)59 ; Decreasing from the equator to the north and south sides.

(4)20 N。

(5) 124 E； 17: 44.

(6) vernal equinox.