Cohorts of stars orbiting black holes (with planets, moons, and eclipses!)

Cohorts of stars orbiting black holes (with planets, moons, and eclipses!)

This post starts off with some world-building, jumps into eclipses and moons’ orbits, and finishes with a brand new Kalgash system that Isaac Asimov would be proud of (dropped into darkness every 2000 years!). More than one planet can share the same orbit around a star. This is not big news: the concept of Trojan…

Real-life Sci-Fi world 11: Kalgash, a planet in permanent daytime (from Asimov’s Nightfall)

Real-life Sci-Fi world 11: Kalgash, a planet in permanent daytime (from Asimov’s Nightfall)

Isaac Asimov‘s sci-fi stories are one reason I wanted to become an astronomer (I talked about this in a recent interview). So I’m a little sad to shoot down a classic…. Nightfall is a classic Asimov story (and later, novel). The residents of a planet called Kalgash live in system of six stars that leaves…

Real-life sci-fi world #6: Pandora (from the movie Avatar), the habitable moon of a gas giant planet

Real-life sci-fi world #6: Pandora (from the movie Avatar), the habitable moon of a gas giant planet

Welcome to Real-life Sci-fi worlds.  I use science to explore life-bearing worlds that are the settings for science fiction stories.  Up today: can the moon of a gas giant planet — like Pandora from the movie Avatar — really be habitable? Pandora is one of the coolest-ever settings for a science fiction story.  The life-bearing…

Real-life sci-fi world #4: Earth around a brown dwarf

Real-life sci-fi world #4: Earth around a brown dwarf

Welcome to Real-life Sci-fi worlds.  We are using science to explore life-bearing worlds that are the settings for science fiction stories.  Up today: an Earth-like planet orbiting a brown dwarf. Setting Planets have been found orbiting all kinds of stars.  Stars like the Sun.  Stars brighter and fainter than the Sun.  Giant stars.  Planets have…

Real-life sci-fi worlds #3: the oscillating Earth

Real-life sci-fi worlds #3: the oscillating Earth

Welcome to Real-life Sci-fi worlds.  We are using science to explore life-bearing worlds that are the settings for science fiction stories.  Up today: the oscillating Earth. Setting Earth’s orbit is not fixed.  Gravitational kicks from the other planets change the shape of Earth’s orbit.  Earth’s orbit oscillates between being perfectly circular (having an “eccentricity” of…