造父變星 的英文怎麼說
中文拼音 [zàofùbiànxīng]
造父變星
英文
cepheid variable-
The longer the period, the brighter the star is. thus, by measuring the period of a cepheid variable, we know its absolute magnitude, hence, we can tell how far it is away by comparing with its apparent magnitude
所以，只要知道某一造父變星的周期，我們便可得知它的絕對星等，只要和它的視星等作比較，便可以求得它和我們的距離。Cepheid variable is the foundation of this ladder
，而造父變星便是這階梯中不可或缺的其中一環。Cepheid variable stars are stars whose brightness changes at regular periods
造父變星是一種光線按規律周期發生變化的恆星。Double - mode cepheid
雙模造父變星This makes space telescope invaluable for identifying a rare class of pulsating stars, called cepheid variable stars embedded within m100 ' s spiral arms
這對于從m100的旋臂中分辨出暗藏的造父變星有著莫大價值。One of the key project of hubble s telescope is to gauge as many cepheid variables as possible in more distant galaxies up to 65 millions light years
哈勃太空望遠鏡的一個重點計劃，就是要測量更多更遠星系中的造父變星遠達Since delta cephei was one of the earliest members of a special kind of variables being discovered, all variables in this family are called cepheid variables or simply cepheids
星的中國名稱為造父一，由於它最早被發現的一種新變星類別，所以這類變星皆稱為造父變星。Cepheid variables are dimmer than the type i supernova. as a result, the supernova allows us to measure the distances of galaxies further away, but it happens much less often
I型超新星比造父變星光亮，所以能夠量度更遙遠星系的距離，唯一缺點是不經常有i型超新星爆發。Astronomers made observations of cepheid variable stars [ pictured above ] ? pulsating stars used to measure vast distances ? in the virgo and other clusters to establish the expansion rate and the universe ' s age
天文學家用哈勃觀測到仙女星座和其它星群中的造父變星（如圖） ，以確定宇宙的膨脹速度和宇宙的年齡。We have to use some other methods to measure the luminosity or equivalently the absolute magnitude of the cepheid variable. since we can readily measure the apparent magnitude of a cepheid variable, to measure the luminosity means measuring the distance. we use some distance measurement methods, for example, parallax, to determine the relation
要弄清這個關系，我們要知道不同造父變星的光度和光變周期數據，量度光變周期當然不是問題，但要得知一顆恆星的光度，我們首先要得知它的距離，這時便須藉助好像視差法等其他量度天體距離的方法。Except those celestial objects of several hundred light years, astronomers rely primarily on cepheid variables for measuring distances of celestial objects. using ground telescopes to gauge cepheid variables enable us to directly measure celestial objects within 20 to 30 millions light years. for more distant stars, other methods have to be used
除了幾百光年內的星體外，天文學家很主要倚靠測量造父變星來計算天體的距離，利用地面望遠鏡測量造父變星，可直接給出約二三千萬光年內星體的距離，而對于更遙遠的星體，天文學家便要藉助其他方法，但這些方法還是需要利用造父變星來作校正。Well, you may ask : how can we determine the luminosity - period relation
但你可能會問：我們怎樣得知造父變星的光變周期光度關系？The hubble space telescope captured the light variation of o e of the cepheids inside the spiral galaxy m100 which is at a distance of 56 million light years away from earth
距離地球五千六百萬光年的旋渦星系m100內，哈勃太空望遠鏡拍得當中一顆造父變星的光度變化Subsequently astronomers found more and more cepheids in different corners of the universe and discovered that there exists a simple relationship between their luminosities and light variation periods
其後的天文學家在宇宙不同角落陸續找到其他造父變星，並發現了它們光度跟光變周期間的簡單關系。By making use of this relationship, astronomers can turn cepheids into celestial yardsticks of the universe, enabling us to easily map the position of galaxies within 100 million light - years
利用這個簡單關系，天文學家使造父變星成了宇宙間的里程碑，讓我們可輕易給那些動輒遠達數千萬光年的星系定位。This usually means that we find out the relation using stars near us, then apply the relation to greater distances. in general, we use accurately determined distance indicators for small distance to calibrate distance indicators for greater distances
事實上，科學家首先找一些離我們較近的造父變星，找出它們的光變周期與光度的關系，然後假設這個關系對遙遠的同類變星依然適用。分享友人