The summer astronomical "big picture" is coming! Perseid Meteor Shower and "Super Moon" Don't Miss Meteor Shower | Eastern Distance | Astronomy
Summer is the best season for observing celestial phenomena. This month, Mercury will appear at a great distance to the east, Perseid meteor showers, and the "super moon" will appear one after another. Shi Wei, Minister of the Network Science Popularization Department of the Shanghai Astronomical Observatory and Deputy Secretary General of the Shanghai Astronomical Society, introduced that the Perseid meteor shower is an unmissable meteor shower. Astronomers should choose clear and dark nights for observation, and can go to open areas near tourist attractions according to weather forecasts to enjoy this summer astronomical "vast area".
The first celestial phenomenon to appear is Mercury at a large distance to the east. Shortly after sunset on August 10th, we can see the figure of Mercury in the low western sky. It is reported that Mercury is the planet closest to the Sun and often disappears in the radiance of the Sun. It is only when the angular distance between Mercury and the Sun is at its maximum, known as the "great distance," that there is hope of seeing it with the naked eye. When Mercury is located to the east of the Sun, it is called the eastern distance, and when it is located to the west of the Sun, it is called the western distance. At a great distance to the east, Mercury can be found above the western horizon at dusk; At a great distance to the west, it appears in the low eastern sky at dawn. For astronomy enthusiasts, observing in the evening is more convenient, so Mercury's eastward distance is more of a concern.
At 19:00 on August 10th, low altitude in the west
Shi Wei stated that this month's appearance of Mercury's eastward maximum distance is the largest of Mercury's three eastward maximum distances this year, reaching 27.4 °. However, due to Mercury's location to the south of the Sun, the horizon height at sunset is not the highest, but it is not much different from the one in April, and it is also the best observation time of the year.
This year's Perseid meteor shower occurred greatly on the morning of August 13th, which is beneficial for Chinese observers and coincides with the weekend. Therefore, many astronomy enthusiasts have prepared to go to the countryside for observation.
In terms of lunar phase, the age of the moon on the morning of August 13th is 26.4, which belongs to the remnant moon. The illuminated part is about 10.3%, and it is about 48 ° away from the radiation point of the Perseid meteor shower. The moon rises from the northeast direction at 2am and may cause some disturbance to the observation after 4am.
The Perseid meteor shower captured on August 12, 2020 in a small town in Austria by Xinhua News Agency/Ouxin
It is reported that the Perseid meteor shower, along with the Quadrant and Gemini meteor showers, is known as the "three major meteor showers in the Northern Hemisphere" and is also known as the "most suitable meteor shower for observation throughout the year" because its peak occurs in summer in the Northern Hemisphere, with stable annual flow and a large number of meteors. Its meteor group has a faster velocity, longer meteor paths, blue-green meteors, and more bright meteors.
On August 31st, the "Super Moon" will make its final appearance. The formation of the "supermoon" originated from the orbital characteristics of the moon's orbit. The orbit of the moon around the Earth is elliptical, with a distance of approximately 350000 kilometers from the Earth at its closest and over 400000 kilometers at its farthest, with an average distance of 380000 kilometers. Therefore, when viewed from Earth, there is a distinction between the "big moon" and the "small moon", with a difference of about 1/8 in apparent diameter between the two. If the moon passes through its perigee and happens to reach a full moon state, it is called a "supermoon".
The minimum and maximum full moons in 2023
The maximum full moon of this year occurred at 9:36 am on August 31st, when the moon was about 357341 kilometers away from Earth and had an apparent diameter of 33 ′ 25.0 ″, which was about 13.5% larger than the minimum full moon of this year. The moon's perigee occurred at 23:54 on August 30th, which was 9 and a half hours away from the moment when the maximum full moon appeared. Of course, this timing sequence will not affect our appreciation of the "super moon". At that time, the public can pay attention and observe whether the "supermoon" is larger than the usual full moon?
