white dwarf 【天文學】白矮星。
【天文學】白矮星。 “white“ 中文翻譯： adj. 1.白(色)的，雪白的；白晰的，帶白色的；蒼白 ...“dwarf“ 中文翻譯： n. 1. 矮小的動物[植物]；矮生植物。 2.【北歐神 ...“c-o white dwarf“ 中文翻譯： 碳氧白矮星“flickering white dwarf“ 中文翻譯： 閃變白矮星“helium white dwarf“ 中文翻譯： 氦白矮星“nonrotating white dwarf“ 中文翻譯： 無自轉白矮星“pre-white dwarf“ 中文翻譯： 白矮前身星“red white dwarf“ 中文翻譯： 紅白矮星“red white dwarf star“ 中文翻譯： 紅白矮星“white dwarf branch“ 中文翻譯： 白矮星支“white-blue dwarf“ 中文翻譯： 藍白矮星“o-ne-mg white dwarf“ 中文翻譯： 氧氖鎂白矮星“winter white russian dwarf hamster“ 中文翻譯： 短尾侏儒倉鼠“dwarf“ 中文翻譯： n. 1. 矮小的動物[植物]；矮生植物。 2.【北歐神話】(善做金屬小工藝品的)矮神。 3.【天文學】矮星 (＝dwarf star)。 adj. 矮小的。 a dwarf car 小型汽車。 vt. 使矮小，使(發育、智能等)受阻礙；使相形見絀。 dwarf all one's rivals 使所有的對手都相形見絀。 a dwarf(ed) tree 盆栽樹，盆景。 vi. 變矮小。 n. -ism 1.矮小。 2.【植物；植物學】矮態；【醫學】侏儒癥。 “dwarf (dwarf star)“ 中文翻譯： 白矮星“dwarf(dwarf star)“ 中文翻譯： 矮星“achondroplastic dwarf“ 中文翻譯： 軟骨發育不全性侏儒; 軟骨營養障礙性矮小“amsterdam dwarf“ 中文翻譯： 阿姆斯特丹侏儒“asexual dwarf“ 中文翻譯： 性欲缺乏侏儒“ateleiotic dwarf“ 中文翻譯： 發育不全侏儒“ateliotic dwarf“ 中文翻譯： 發育不全性侏儒“belgian dwarf“ 中文翻譯： 比利時侏儒兔“black dwarf“ 中文翻譯： 黑矮星“blue dwarf“ 中文翻譯： 藍矮星“brown dwarf“ 中文翻譯： 褐矮星; 棕矮星
white elephant |
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Matter will be transferred from the red giant to the white dwarf when the gravity of the red giant at its surface is weaker than that of the white dwarf . when sufficient matter is accreted onto the surface of the white dwarf , nuclear reactions will start and sustain for a short period on the white dwarf surface . enormous energy is produced 當紅巨星的表面引力比白矮星弱時，部分物質會盤旋流進白矮星內，當足夠的物質積聚在白矮星表面，便會燃點起熱核反應，產生出巨大的能量，這種爆發會維持下去，直至所有氫氣耗盡。 |
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The temperature range of quasisoft x - ray sources falls just right for an accreting black hole that is more massive than a stellar - mass black hole . however , we should be cautioned that in principle , the low temperatures of many quasisoft x - ray sources can be explained by stellar - mass black holes , neutron stars , and even white dwarfs under very specific physical conditions 就以類軟射線源的溫度范圍來說，雖然它完全符合那些比恒星型黑洞更大的吸積黑洞，但有一點不能忽略，就是這個溫度在理論上也可以是由恒星型黑洞中子星甚至白矮星在一些特殊物理情況下產生。 |
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If the mass of the core after a supernova explosion is more than 1 . 4 but less than about 3 solar masses , then electron degenerate pressure is not strong enough to support the star . the star will contract to a size even smaller than the white dwarf . the electrons are squeezed into the nuclei and are combined with the protons to form neutrons 假若在超新星爆發后，剩馀核心質量介乎太陽質量的1 . 4至3倍，那么核心中的電子簡并壓力便再不足以抵抗強大的引力，恒星會進一步收縮，直至電子亦被擠壓至原子核內，和質子結合成為中子。 |
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Topics include : planets , planet formation ; stars , the sun , “ normal “ stars , star formation ; stellar evolution , supernovae , compact objects ( white dwarfs , neutron stars , and black holes ) , plusars , binary x - ray sources ; star clusters , globular and open clusters ; interstellar medium , gas , dust , magnetic fields , cosmic rays ; distance ladder ; galaxies , normal and active galaxies , jets ; gravitational lensing ; large scaling structure ; newtonian cosmology , dynamical expansion and thermal history of the universe ; cosmic microwave background radiation ; big - bang nucleosynthesis 課程的主題包含了：行星、行星形成；恒星、太陽、正常的恒星、恒星形成；恒星演化、超新星、致密天體(白矮星、中子星及黑洞) 、波霎、雙x -射線源；星團、球狀及疏散星團；星際介質、氣體、塵埃、磁場、宇宙射線；距離階梯；星系、正常及活躍星系、噴流；重力透鏡；大尺度結構；牛頓宇宙學、宇宙的動力膨脹及溫度發展歷史；宇宙背景微波輻射；大霹靂核合成。 |
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More recently , dr . rosanne di stefano also from the harvard - smithsonian centre for astrophysics and i used the chandra x - ray observatory to detect objects dubbed “ quasisoft “ x - ray sources in nearby galaxies because of their low temperatures , which are at most four million degrees celsius . that is well below the temperatures expected for “ hard “ x - ray sources such as neutron stars or stellar mass black holes - which run between 10 million and 100 million degrees celsius - and still hotter than “ soft “ x - ray sources like white dwarfs 最近羅珊迪史提芬路博士她亦來自哈佛大學史密森天體物理中心和筆者利用錢德拉射線天文臺在鄰近星系偵測到一種奇怪的-射線源，我們稱之為類軟射線源，因為它們的溫度最高只有攝氏400萬度，遠低于一般硬射線源，例如中子星和恒星型黑洞溫度介乎攝氏1千萬至1億度，卻又比軟射線源例如白矮星為高。 |
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In general , ba stars belong to binary system , and their heavy - element overabundances are due to the accreting material from the companions ( the former tp - agb stars and the present white dwarfs ) . carrying out a series of monte - carlo simulations , the changes of orbital elements of binaries are recalculated for wind accretion scenario of the total angular momentum conservation 研究表明，鋇星應該屬于雙星系統，其重元素超豐來自雙星吸積，它的伴星已經經歷了s -過程核合成，而且由在以前發生的同其伴星(以前是agb星，現已演化為白矮星)的質量傳輸過程中，從伴星那里獲得了富含重元素的物質，這樣造成了鋇星的重元素超豐。 |
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In a binary system , situations may become more complicated . for example , it could happen that one has evolved to a white dwarf figure to and the other is becoming a red giant . the two could be very closed to each other , maybe only about the earth - moon distance see figure to 在雙星系統里，有可能其中一顆恒星已演化為白矮星參閱a圖至d圖，但另一顆恒星只達紅巨星階段，而它們之間的距離和地月距離差不多參閱d圖至f圖。 |
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After 100 , 000 to one million years , depending on the original mass of the star , it ceases altogether , and the remnant star settles down as an extremely dense and hot white dwarf ? a stellar ember crushed by gravity into a nearly crystalline orb about the size of earth 經過10 ~ 100萬年（取決于恒星的原始質量） ，恒星風將驟然終止，而恒星的殘留物會演變成極致密高熱的白矮星：一種被重力擠壓成地球般大小，近乎晶質球體的恒星遺骸。 |
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Five billion years later , it will evolve along the curve to become a red giant . it will be unstable and eject the shell forming a planetary nebula , then move quickly along the curve to become white dwarf at the lower left 五十億年之后，太陽將會演化為一顆紅巨星，這個階段的恒星十分不穩定，最終將會把外殼拋掉，形成行星狀星云。 |
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The evolution of fixed star having something to do with nuclear reaction , the star generally loses partial mass in its final period and finally collapses into compact star ( white dwarf , neutron star or black hole ) 恒星的演化與核反應有關，演化到晚期的恒星一般要損失一部分質量，然后坍縮成致密星(白矮星、中子星或黑洞) 。 |
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It ' s customary among the stars to quietly burn the hydrogen they are made of , generously giving energy to the void , until they are reduced to a dignified thinness and end their career as modest white dwarfs 恒星，慣常是安靜的燃燒組成它們本身的氫，向空間里散發能量，直到達到一定的體積大小，它們作為白矮星的一生就抵達終點。 |
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This and the x - ray spectrum , which exhibits a high concentration of iron atoms relative to oxygen and silicon , convincingly show that the ejecta are the remains of an exploded white dwarf star 這幅圖連帶x射線光譜（顯示出了鐵相對氧與硅的高度集中）令人信服地說明，拋出的物質是爆發白矮星的殘余。 |
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Measuring 2 , 500 miles across and weighing five million trillion trillion pounds , the rock was found on valentine ' s day buried in the core of a white dwarf star in the constellation centaurus 這塊石頭直徑達2500英里，重5 10的42次方磅，藏在人馬座中一顆白矮星的中心，是在情人節那天被發現的。 |
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When it dies ( by swelling to become a red giant , a planetary nebula and finally a white dwarf ) , it will be much hotter than other , older white dwarfs of similar mass 當它（膨脹成紅巨星、行星狀星云并最后變成白矮星）死亡時，它的溫度將比其他質量相近的年老白矮星，要高上許多。 |
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The collapse of a star may produce a white dwarf or a neutron star ? a star , whose matter is so dense that it continually shrinks by the force of its own gravity 一些星星的瓦解可能會產生一顆白矮星或一顆中子星?一顆星，那些東西是如此的密集以至于被它們自己的引力不斷的縮短。 |
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Data from the chandra observation show that the central ten - million - degree celsius cloud is the remains of a supernova explosion that destroyed a white dwarf star 來自錢德拉的觀測數據表明，中心溫度達上千萬攝氏度的云湍團是超新星爆發的殘余，爆發摧毀了一顆白矮星。 |
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Meanwhile the agent of this catastrophe , the white dwarf , would continue blithely on its way ? not that we would be around to care about the injustice of it all 與此同時，此次大禍的元兇白矮星，則輕快地繼續它的旅程不消說，我們已無緣待在那里抗議不公平了。 |
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It has ejected masses of dust and gas and now for a few hundred thousand years , it is in this temporary state before it becomes what is known as a white dwarf 星云就是即將消逝的星體，它所含有的氦已經慢慢消失，然后產生內爆，這種暫時的狀態要維持數十萬年。 |
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After the explosion , if the mass left is less than 1 . 4 solar masses , a white dwarf will form . if it is between 1 . 4 to about 3 solar masses , a 在大爆炸后，若剩馀質量少于1 . 4個太陽質量，便會成為白矮星若質量介乎1 . 4至大約3個太陽質量，便會成為 |