On July 31, Mars and the Earth "great approach", and Mars, whose brightness increased in the southeast night sky, shines brightly red.
This year's hot astronomical show.
Both Mars and Earth travel around the sun, but since the rotation speed of the Earth that rotates inside is faster, the closest approach to passing Mars every two years and two months before the meeting.
The distance is different every time, divided into small approach, medium approach, and large approach. This time, the geocentric distance is 57.59 million km, which is the first "large approach" in 15 years. Mars on this day is brighter than the first magnitude star, minus 2.8 mag.
It can be seen enough in the bright city center of the sky.
Until early September, it is the season of starry sky watching that makes it easy to observe Mars of minus 2 grade.
