Chinanews client, Beijing, August 13th (Reporter Shangguanyun) As an anticipated "astronomical blockbuster" in the night sky in August, the Perseid meteor shower ushered in its maximum period on the evening of August 12 and the meteors struck The beautiful photos of the night sky also began to refresh.
Some netizens regret that the meteor shower could not be observed due to rain or other objective reasons. According to experts, there will be a Geminid meteor shower in December this year, and the flow is relatively stable. In addition, there are these "little secrets" for the formation of meteor showers.
When is the Perseid meteor shower active?
The observation history of the Perseid meteor shower is very long, and it is also known as "Saint Laurent's Tears".
Data map: On the evening of August 12, the Perseid meteor shower, one of the three largest meteor showers in the northern hemisphere, appeared in the night sky. On the top of Huangshan Mountain in Anhui, meteors travel through the Milky Way to complement each other. The starry sky is shining, the mountains stretch, and the summit of Huangshan Mountain is magnificent. Mei Jianshe
It is one of the three major meteor showers in the northern hemisphere, and the other two are the Quadrantid meteor shower and the Gemini meteor shower. However, the Perseid meteor shower appears in the northern hemisphere in summer, and for astronomers, the observation conditions are more comfortable.
According to reports, meteors belonging to the Perseid meteor group have a relatively fast speed of up to 59 km/s and belong to the high-speed meteor group. The time for the meteor itself to traverse the night sky is only a few tenths of a second, and some of the brighter meteors will leave a trail for several seconds after flashing.
However, many netizens pointed out that because of rain or other observational conditions, they did not enjoy the beauty of the dense meteor shower across the sky last night.
In fact, the annual activity period of the Perseid meteor shower is from July 17 to August 24, lasting for more than a month. In theory, the ZHR (zenith rate per hour) of this meteor shower is about 80-120.
"This time the maximum period of the Perseid meteor shower is on the 12th. After the maximum value, the flow rate will decrease, but if the observation conditions are suitable, it can still be seen in the next few days." National Astronomical Observatory of Chinese Academy of Sciences Li Geng, associate researcher, said.
The "little secret" of the meteor shower
Another point of knowledge about meteor showers is that it is generally believed that most meteor showers originate from the "fragments" left by comets in their orbits.
Data map: Star track map and Perseid meteor under multiple exposures in Yangtiangang National Forest Park, Xinyu City, Jiangxi Province. Photo by Zhao Chunliang
Generally speaking, a comet orbits the sun in a flat elliptical orbit, and every time it approaches the sun, some ice or other matter is thrown out to stay in the orbit.
Li Geng said that when the orbit of the earth intersects the orbit of the comet, the above-mentioned "fragments" thrown out will rush into the atmosphere and form a meteor shower. Because the earth passes through this "fragment belt" every year, that's why the dates we see specific meteor showers are basically the same and very regular every year.
It is worth noting that the "mother body" of the Perseid meteor shower is a comet named 109P/Swift-Tuttle. The return period of this comet is approximately 130 years.
"For example, every time this comet comes back, it will leave a bunch of new'fragments' again, so this'fragment belt' always exists." Li Geng explained.
On August 12, 2019 local time, Belarus, a Perseid meteor shower crossed the night sky on the ruins of a medieval castle in the village of Kriva, about 100 kilometers northwest of Minsk.
In December, the Geminid meteor shower can be expected
Many astronomers are looking forward to the beautiful meteor shower. Some media have summed up viewing strategies, such as going to a place with a wide view, and going to the outskirts away from city lights.
Li Geng said that observing meteor showers is not difficult and does not require special equipment. To view with the naked eye, just look for a relatively dark and flat place, find the direction of the meteor shower radiant point, and then wait and see.
However, due to the influence of ground light, moonlight, etc., the actual number of meteors that people look like will be less than the value of ZHR, so watching a meteor shower requires a little patience and luck.
In addition, on December 14 this year, there will be the famous Gemini meteor shower, and the annual flow of it and the Perseid meteor shower is relatively stable. It is said that when the Gemini meteor shower reaches its peak, several meteors will appear every minute, so it is also known as the "king of meteor shower." Will you watch this meteor shower? (Finish)