91福利

White Dwarf Suns: Can Dead Stars Support Life in the Current and Future Universe?

The majority of stars in our Galaxy, and in other galaxies throughout the Universe, will eventually evolve into white dwarfs. This notably includes our own Sun. The effects that this process will have on the Solar System at large are of intrinsic interest to its inhabitants, since the consequences of the Sun's post-main sequence evolution will determine the Solar System's future contents and suitability for supporting life. Due to the presence of accreted photospheric metals and/or infrared excesses indicative of circumstellar dust disks, some white dwarfs are already known to harbor the remnants of a planetary system. Recently, this has been bolstered by the first detection of a dwarf planet-sized object transiting a white dwarf. Thus, if planetary systems can survive the post-main sequence evolution of their parent star, then white dwarfs will also become the most common hosts for planets in the future and, by extension, potential sites for the continuing existence of life as the Universe ages. I will review the effects on a planetary system of its host star's evolution into a white dwarf, and discuss the implications for providing conditions around the remnant white dwarf that can nominally support life (e.g., a planetary body with liquid water), resulting from both luminous and non-luminous energy flux.