Tiangong-1 launches solar terms

As can be seen from the schematic diagram of the earth's revolution, when the earth is in position ①, the sun is on the tropic of cancer, which is the summer solstice in the northern hemisphere, and the date is around June 22nd. When the earth is located at ② position, the latitude of direct sunlight is equator, which is the autumn equinox in the northern hemisphere, and the date is around September 23rd. When the earth is at ③ position, the latitude of direct sunlight is tropic of Capricorn, which is the winter solstice in the northern hemisphere, and the date is about 65438+February 22nd. When the earth is at ④ position, the latitude of direct sunlight is equator, which is the vernal equinox in the northern hemisphere, and the date is about March 2 1.

On September 30th, 20 1 1, Tiangong-1 was successfully launched from Jiuquan Satellite Launch Center, which is the closest to the autumnal equinox among the four solar terms, that is, near ② in the figure.

Therefore, choose: B.