现在看看天上，南边天空上的一颗亮的星星是什么星？
- 主题发起人 cvictor
- 开始时间
the Dog Star ---sirius
How to see Sirius. Most people in the Northern Hemisphere notice Sirius in the southeast – south – or southwest on evenings from winter to mid-spring. February evenings are a grand time to see it. It’s also fun to spot Sirius as it ascends in the east before dawn on late summer mornings. Whenever you see Sirius, you’ll recognize it easily because it is our sky’s brightest star.
Although white to blue white in color, Sirius might be called a rainbow star, as it often flickers with many colors.
The brightness, twinkling and color changes sometimes prompt first-time observers to report Sirius as a UFO. But these changes have nothing to do with Sirius. Rather, they are what happens when such a bright star as Sirius shines through the blanket of Earth’s atmosphere. The light from Sirius, which often appears fairly low in the sky from the mid-north latitudes, passes through a long column of air before it reaches our eyes. Changes in density and temperature of this air affect the light and cause the flickering and shimmering we see when we gaze at this star. This happens for other stars, too, but it is more noticeable for Sirius because it is so bright, and because it appears low in the sky.
From the mid-northern latitudes such as most of the U.S., Sirius rises in the southeast, arcs across the southern sky, and sets in the southwest. In December, you’ll find Sirius rising in mid-evening. By mid-April, Sirius is setting in the southwest in mid-evening.
Sirius is always easy to find. It’s the sky’s brightest star! Plus, anyone familiar with the constellation Orion can simply draw a line through Orion’s Belt, to the left. This line will point to Sirius, which is roughly 8 times as far from the Belt as the Belt is wide.
Although white to blue white in color, Sirius might be called a rainbow star, as it often flickers with many colors.
The brightness, twinkling and color changes sometimes prompt first-time observers to report Sirius as a UFO. But these changes have nothing to do with Sirius. Rather, they are what happens when such a bright star as Sirius shines through the blanket of Earth’s atmosphere. The light from Sirius, which often appears fairly low in the sky from the mid-north latitudes, passes through a long column of air before it reaches our eyes. Changes in density and temperature of this air affect the light and cause the flickering and shimmering we see when we gaze at this star. This happens for other stars, too, but it is more noticeable for Sirius because it is so bright, and because it appears low in the sky.
From the mid-northern latitudes such as most of the U.S., Sirius rises in the southeast, arcs across the southern sky, and sets in the southwest. In December, you’ll find Sirius rising in mid-evening. By mid-April, Sirius is setting in the southwest in mid-evening.
Sirius is always easy to find. It’s the sky’s brightest star! Plus, anyone familiar with the constellation Orion can simply draw a line through Orion’s Belt, to the left. This line will point to Sirius, which is roughly 8 times as far from the Belt as the Belt is wide.
不是Sirius, 是金星。Sirius看起来只比普通星星亮一点。
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