Mercury East is staged on the 28th, the public is expected to see Mercury's beautiful shadow

Poster production: Feng Juan

On August 28, Mercury will usher in the fifth distance of 2022 and the third Dongda distance. Astronomical popular science experts said that during the large distance, Mercury's height was a bit low, and it was difficult to observe. At that time, if the weather is fine, the interesting public can use the binocular telescope or a small astronomical telescope to try to find the mysterious figure of Mercury on the southern part of the west part that day.

This is a photo of Mercury taken by Mercury probe in the United States. Xinhua News Agency/Reuters

Mercury is a planet closest to the sun. From the perspective of the earth, it always swings back and forth within a certain range near the sun. Because it is too close, Mercury is drowned in the glory of the sun all year round, and it is difficult to be observed. Only when the distance between Mercury and the sun is the largest, that is, "big distance" can people be more likely to observe Mercury at dawn or dusk.

Mercury's big distance schematic production: Hu Yanzhu

There are east and west. From the perspective of the earth, Mercury is called the east to the east of the sun, and it is called the west distance in the western side of the sun. Before and after Dongda, Mercury appeared above the western horizon at dusk. During this period, it was called "faint star"; before and after the west distance, Mercury appeared at the low altitude at the low altitude at dawn. Essence

Comic production: Hu Yanzhu

Because the eccentricity and inclination of Mercury's orbital are relatively large, each time the distance is large, the distance between Mercury and the sun changes between 18 degrees and 28 degrees. "During the distance of the Dongda distance, the distance between Mercury and the sun was 27 degrees, and the brightness was about 0.2, which was a visible range of the naked eye." Said Song Yuanyuan, a member of the Tianjin Astronomical Society and an astronomical popular science expert from Tianjin Science and Technology Museum.

Because Mercury operates around the sun for a short time, it is only 88 days, so there will be at least 6 and up to 7 times a year of Mercury. "Mercury has a total of 7 times in 2022. Among them, there are 3 times in the west and 4 times. At the end of August, this time is the worst observation condition." Song Yuanyuan said.

Whether Mercury is easily observed does not depend on the angle of the distance from the sun at a large distance, and more importantly, its horizon height during the sunrise or sunset.

"At this time, although Mercury's distance is large enough, Mercury's horizon is only 9 degrees, which is too low. If the low altitude transparency is not good, or there are some obscuration in the south of the west, it is difficult for the public to use it. See Mercury with the naked eye. "Song Yuanyuan said.

On April 29, 2022, Mercury east, Tianjin astronomical enthusiast Yang Jing, who shot in Tianjin on the evening of May 1, 2022 in Tianjin. (I have a picture)

Of course, the time to observe Mercury is not limited to the day of August 28, but more than 20 days before Dongda's distance. "During this period, Mercury's horizon will be higher, but it is still a bit low. Interested public can be observed from the sun for an hour after the sun. At this time, it is not completely dark. The telescope, "Song Yuanyuan said.

(Original title: Mercury East Big distance staged on the 28th, the public is expected to see Mercury's beautiful shadow)