傷心了，原圖太大，B站導入失敗。。。沒事，這有優(yōu)化版。

The Whirlpool Galaxy is a classic spiral galaxy. At only 30 million light years distant and fully 60 thousand light years across, M51, also known as NGC 5194, is one of the brightest and most picturesque galaxies on the sky. The featured image is a digital combination of images taken in different colors by the Earth-orbiting Hubble Space Telescope, highlighting many sharp features. Anyone with a good pair of binoculars, however, can see this Whirlpool toward the constellation of the Hunting Dogs (Canes Venatici). M51 is a spiral galaxy of type Sc and is the dominant member of a whole group of galaxies. Astronomers speculate that M51’s spiral structure is primarily due to its gravitational interaction with the smaller galaxy on the image left.

渦狀星系是個經(jīng)典的螺旋星系。離我們只有3千萬光年遠、寬為6萬光年、亦稱為NGC 5194的M51，是天空最明亮最美麗的星系之一。上面這幅主題影像，是由地球軌道上的哈勃太空望遠鏡攝于不同顏色波段的照片數(shù)位組合而成，以突顯數(shù)個不同的特征。不過，任何擁有一具好雙筒望遠鏡的觀星者，都應能在北天的獵犬座方向見到這個渦旋狀的美麗星系。M51的分類為Sc型螺旋星系，也是它所在的星系團最龐大之成員星系。天文學家認為M51的螺旋結構，主要是它與位在影像左側的小星系重力互擾下的產物。

明日預告：pinnacle satellites