Potential For Life
The primary component has a metallicity of =−0.19, i.e. about 65 per cent of the solar metallicity, thus providing a probably sufficient heavy element abundance for the formation of terrestrial planets. However, no planet orbiting a member of 40 Eridani is known so far. The habitable zone of 40 Eridani A, where a planet could exist with liquid water, is near 0.68 (calculated from habitable zone) AU from A. At this distance a planet would complete a revolution in 223 Earth days (according to the third Kepler's law) and 40 Eridani A would appear nearly 20% wider than the Sun does on Earth. An observer on a planet in the 40 Eridani A system would see the B/C pair as unusually bright (magnitudes -8 and -6) white and reddish-orange stars in the night sky. This is not bright enough to diminish the darkness at night, though they would be visible in daylight (assuming an Earth-normal atmosphere). (By comparison, Earth's full moon is magnitude −12.6, and Venus at its brightest is −4.7.) It is extremely unlikely that habitable planets exist around the B star because planets circling 40 Eridani B would probably have been destroyed or sterilized by its evolution into a white dwarf. As for 40 Eridani C, it is prone to flares, which cause large momentary increases in the emission of X-rays as well as visible light. This would be lethal to life on a planet in the habitable zone.
Read more about this topic: 40 Eridani
Famous quotes containing the words potential for, potential and/or life:
“While each child is born with his or her own distinct genetic potential for physical, social, emotional and cognitive development, the possibilities for reaching that potential remain tied to early life experiences and the parent-child relationship within the family.”
—Bernice Weissbourd (20th century)
“The planet on which we live is poorly organized, many areas are overpopulated, others are reserved for a few, technology’s potential is only in part realized, and most people are starving.”
—Friedrich Dürrenmatt (1921–1990)
“Since it is impossible to know what’s really happening, we Peruvians lie, invent, dream and take refuge in illusion. Because of these strange circumstances, Peruvian life, a life in which so few actually do read, has become literary.”
—Mario Vargas Llosa (b. 1936)