Illustration Credit & Copyright: Mark A. Garlick(Space-art.co.uk)
Explanation: Will this dawn bring another nova?Such dilemmas might be pondered one day by future humans living on a planet orbiting a cataclysmic variablebinary star system. Cataclysmic variables involve gas falling from a large star onto an accretion disk surrounding a massive but compact white dwarf star. Explosive cataclysmic events such as adwarf novacan occur when a clump of gas in the interior of the accretion disk heats up past a certain temperature. At that point, the clump will fall more quickly onto thewhite dwarf and land with a bright flash.Such dwarf novas will not destroy either star, and may occur irregularly on time scales from a few days to tens of years. Although a nova is much less energetic than a supernova, ifrecurrent novas are notviolent enough to expel more gas than is falling in,mass will accumulate onto the white dwarf star until it passes its Chandrasekhar limit. At that point, a foreground cave may provide little protection, as the entire white dwarf star will explode in a tremendous supernova.
插圖提供與版權: Mark A. Garlick (Space-art.co.uk)
說明:
這次黎明是否會帶來另外一顆新星呢?這可能是當未來人們居住的行星,運轉於一個激變星的雙星系統下所需要擔憂的事情。激變星涵蓋了巨星上氣體物質掉入環繞著其巨大且緊實的白矮星,而產生圍繞白矮星的吸積盤。猛烈性的激變事件,是當吸積盤加熱內部的氣體達到一定溫度時,而產生矮新星,此時,氣體會快速地被白矮星吸引過去而轉變成一瞬閃光,這樣的矮新星並不會破壞任何恆星,出現在數天到數年的不規則的時間尺度下。雖然新星能量低於超新星,假使復發新星不夠猛烈而使拋射物質低於吸入物質的話,質量會累積到白矮星直到到達錢卓極限,此時,白矮星會爆炸成巨大的超新星,而前景的洞穴也無法提供任何的保護。