来自蛇夫RS白矮星的新星爆发

2021年8月22日

Explosions from White Dwarf Star RS Oph
Illustration Credit & Copyright: David A. Hardy & PPARC

Explanation: Spectacular explosions keep occurring in the binary star system named RS Ophiuchi. Every 20 years or so, the red giant star dumps enough hydrogen gas onto its companion white dwarf star to set off a brilliant thermonuclear explosion on the white dwarf’s surface. At about 5,000 light years distant, the resulting nova explosions cause the RS Oph system to brighten up by a huge factor and become visible to the unaided eye. The red giant star is depicted on the right of the above drawing, while the white dwarf is at the center of the bright accretion disk on the left. As the stars orbit each other, a stream of gas moves from the giant star to the white dwarf. Astronomers speculate that at some time in the next 100,000 years, enough matter will have accumulated on the white dwarf to push it over the Chandrasekhar Limit, causing a much more powerful and final explosion known as a supernova. Starting early this month, RS Oph was again seen exploding in a bright nova.

Tomorrow’s picture: one galaxy tripled

来自蛇夫RS白矮星的新星爆发
图示版权与提供: David A. Hardy & PPARC

说明: 在名为蛇夫RS的双星系统里，壮观的爆炸不停的重覆发生。大约每隔20年，当红巨星倾泄足量的氢气到它的白矮伴星之后，就会在白矮星的表面触发炽亮的热核爆炸。让离我们有5,000光年远的蛇夫RS星，因新星爆炸而大幅增亮，成为肉眼可见的天体。在上面这幅图示中，右方的天体就是这颗红巨星，白矮星则位在左侧明亮吸积盘的中心。随着恒星相互绕行，云气不断地由红巨星流向白矮星。天文学家认为在接下来100,000年的某个时间点，当足量的物质累积在白矮星上，让它的质量超过钱氏极限时，就会造成远更强烈的终结性超新星爆炸。在这个月稍早发现，蛇夫RS星又发生明亮的新星爆发。

明日的图片: one galaxy tripled