What important astronomical phenomena can be observed in the Yangtze River basin in China this Augus

15.The expression of the perfect law is wrong, so it is excluded and B is selected.

16.It is not reflected in the material, so choose B.

August 6 Penumbral lunar eclipse.

August 13 The Perseid meteor shower is extremely large.

August 15 Jupiter at opposition.

August 18 Neptune opposition.

August 25 Mercury's greatest eastern elongation.

On the evening of August 6, Jupiter is accompanied by the Moon in the southeast.

August 15 at 2 a.m. Jupiter opposition Magnitude Capricorn constellation August 15 at 11 a.m. Jupiter's closest Earth apparent radius"Jupiter is the largest planet in the solar system. At opposition, the Earth is halfway between the Sun and Jupiter, and the three are almost in a line, with the Sun setting in the northwest and Jupiter rising in the southeast. At this time, Jupiter's brightness increases to its maximum.

Through small astronomical telescopes, it is also possible to see Jupiter's four large moons, its four large moons. So far, scientists have discovered more than 60 moons of different sizes on Jupiter. Telescopes with larger aperture are also able to see Jupiter's cloud streaks.

August 18 Venus with the Moon in the northeast of dawn.

August 13 The Perseid meteor shower is extremely large.

As one of the three major meteor showers in the Northern Hemisphere, the Perseid meteor shower has a relatively stable flow, and the lowest ZHR value can reach about 100. In other words, it is very normal to see about 60 in an hour at maximum time. According to the forecast, there will be two maximums for the meteor shower this year, from 13:00 to 15:30 on August 13 and at 23:00 Beijing time.

It coincided with the first day of the seventh month, and the moonlight would not interfere with it all night. The Perseid meteor shower has a large number of bright stars and a moderate velocity of meteors, making it suitable for both visual and photographic observations.

August 14 Neptune at opposition.

Neptune is the only planet that we can't see with the naked eye, and it is only equal at opposition. In telescopes with longer focal lengths and greater magnification, Neptune is a celestial object with a dark blue visual surface. Now Neptune is in Capricorn.

August 28 Total lunar eclipse (only partial eclipse can be seen).

At 120°E standard hour, the penumbral eclipse begins at 15h52m

The initial loss was 16h51m

Food both 17h52m

The food is even 18h37m

Shine 19h23m

Restoration 20h24m

Penumbral eclipse terminal 24h22m

There will be a penumbral lunar eclipse on August 6, but the lunar eclipse will occur at dawn, most of China will not be able to observe, and this lunar eclipse is a small part of the moon into the penumbra of the earth, even if the shadow of the earth casts the largest area on the lunar surface, there is no obvious change with the naked eye. The Perseid meteor shower on August 13 is undoubtedly the highlight of the summer night sky, the most stable meteor shower of the three major meteor showers in the Northern Hemisphere has begun to move, according to the analysis of the International Meteor Shower Organization, the hourly zenith flow of the meteor shower has reached 20, if the traditional flow will reach 100 at the maximum, but according to foreign astronomers' calculations, the hourly zenith flow of the Perseid meteor shower will reach 200, and the actual situation needs to be known after actual observation. The Earth may pass through the eruption of two meteor shower mother comets Swift-Tuttle many years ago during this meteor shower performance, but it was daytime in China at that time, fortunately China is more favorable to the traditional great observation, but the moonlight on the 23rd day of the lunar calendar will have a certain impact on the observation in the second half of the night.

Observers try to go to the open terrain and less lit suburbs to make observations, and they can go into battle soon after dark. Let's wait and see what kind of performance the Perseid meteor shower will perform this year! Jupiter at opposition on August 15, the sun sets in the west and Jupiter rises in the east, and Jupiter can be seen throughout the night, because Jupiter's retinitude with the sun is 180 degrees different from the sun, which means that the sun is on one side of the earth and Jupiter is on the other side of the earth from outside the earth.

Jupiter is the largest planet in the solar system (note that there is no such thing as a "big planet" anymore), and it is the bright white star that has been seen in the southeast recently, and the stripes and the Great Red Spot above can be seen with a small and medium-sized telescope, as well as the four Galilean moons that orbit Jupiter. In addition, Neptune's position is near Jupiter, which means that the day of Neptune's opposition to the Sun is not far from Jupiter's opposition.

August 18 is the day of Neptune's opposition. Neptune is a gas planet like Jupiter, but it's so far away that we can only see the circle with a medium-sized telescope, and it's even more difficult to see the details. August is a great time to observe the celestial bodies of the solar system, and if you haven't seen Mercury, the closest planet to the Sun, you can't miss Mercury's eastern elongation on August 25.

The so-called great elongation means that the distance between the celestial bodies within the Earth's orbit and the Sun in the sky is the maximum on the Earth, and the eastern elongation of Mercury means that Mercury will be on the east side of the Sun and reach the farthest apparent distance from the Sun (note that it is not the actual physical distance). Because it is the largest eastern elongation, it has to be observed after sunset, because the declination of Mercury is lower than that of the Sun this time, so the altitude of Mercury after sunset is also very low, which requires a high observation environment, requires fine weather and an unobstructed western horizon, and also requires observers to search carefully to be able to see.

This year's Perseid meteor shower peaked around 9 p.m. on August 12, and the best place in the world to observe it was the Hawaiian Islands in the United States. In China, there are two mornings of continuous observation: one is from 1 a.m. on August 12 to before dawn; The other is from 0:00 a.m. to before dawn on August 13.

Two early mornings: the eastern part of China is basically unaffected by moonlight in the early morning of the first morning, but the number of meteors observed is relatively small; The first half of the latter morning was slightly disturbed by moonlight, but a relatively high number of meteors were observed.

1. Maximum point estimate: around 0:40 and 5:30 on the 13th.

2. Observation direction: northeast of the sky [because the radiant of the Perseid meteor shower does not rise from the horizon until 22 o'clock, and rises higher in the second half of the night].

The best time to observe this year is in the dark night sky just before dawn on August 12. If it is cloudy on that day, observations on the 11th and 13th are also important. Try observing the moon in the first half of the night for a few hours before it rises.

Unfortunately, at that time, the height of the radiant was still very low, and only a small percentage of the meteors in the group could be observed. At this time, the observed meteors of the Perseid meteor group usually have a long trajectory and produce meteor remnants, but they are very rare. There is no geographical restriction on the observation of meteor showers, as long as the weather is fine, you can observe it with the naked eye!!

This should be done by choosing a good location and bringing an astronomical telescope.

When the moon turns between the earth and the sun, the moon blocks the sun's light shining on the earth, leaving a ring area on the moon, we can't see the sun, which is a solar eclipse; Figure 1 can be drawn according to the relationship between the diameter and distance of the three spheres, and a total solar eclipse will be seen in the darkest region of the earth, and a partial or annular solar eclipse will be seen in other regions; Therefore, the option CD does not fit the topic;

When the earth, the sun, and the moon are in the same straight line, and the earth is in the middle of the moon and the sun, the sun's rays cannot reach the moon, so when the moon is observed on the earth, there is an area where shadows appear, which is a lunar eclipse; According to the relationship between the diameter and distance of the three spheres, Figure 2 can be drawn, the radius of the Moon is smaller than the radius of the Earth, and it is close to the Earth, and the Moon will have a total lunar eclipse or a partial lunar eclipse in all or part of the shadow of the Earth, but there will be no annular lunar eclipse; Therefore, option B does not fit the topic, and option A does not fit the topic

Therefore, a

If you want to find Beidou recently, it can be said that it is quite unfavorable, because recently it rises to the highest time at 9 o'clock in the morning, and more than 9 o'clock in the evening is the lowest time, and the southern region is not visible at 9 o'clock in the evening, because it sinks below the horizon, and the north can only find it very close to the northern horizon.

If the landlord has to see them, then look for them in the morning, when the sun has not yet risen, and they form a big spoon in the northeast sky.