The Star Wars movies popularized the idea that a planet could orbit more than one star. The famous scene where Luke Skywalker gazes over the planet Tatooine’s double-sunset seemed impossible, however, circumbinary planets are more common than previously believed. In fact, up to eighty-five percent of the stars in the Milky Way are in binary systems, most of them with exoplanets.

Yet even though the idea of a dual (or even more) star system is exciting, it can’t hurt to wonder: are two suns better than one?

Since a circumbinary planet orbits more than one star, it gets more than one gravitational pull. Unfortunately, this means that most of the planets’ orbits would be unstable. An unstable orbit could lead to the planet being flung from its system and possibly becoming a nomad (a planet without a sun). This would make it excruciatingly cold, but it might be favorable to meeting a fiery death in a collision with one of its stars.

On the contrary, more suns could mean more energy. As sunlight is the foundation for life on earth, having multiple stars could increase the chances of life evolving by providing separate types of sunlight depending on the luminosity of each star. Additionally, two mid-sized stars would have a longer lifespan than one giant or supergiant star (the life of the system relies on one of the two stars which would be smaller than a giant, and smaller stars have longer lives) and have added energy compared to a single mid-sized star. This means that the “Goldilocks Zone” of the solar system could be larger while leaving more time for life to develop. Following the Karadashev scale, a Type II civilization’s technological advancement depends on the energy available in its solar system. In some cases, two stars would have more energy than one and therefore, the potential for higher advancement.

In conclusion, binary stars are not just science fiction, but very real. Whether they are superior to a single star system like the Sun would depend on the situation. However, the prospect of alien worlds with dual suns is certainly thrilling. I know I’m not alone in the hope for space travel to take us there one day.

Related Articles:

https://warwick.ac.uk/newsandevents/knowledgecentre/science/physics-astrophysics/two_star_planets/

https://phys.org/news/2021-04-star-potentially-suitable-life.html

https://blogs.scientificamerican.com/cocktail-party-physics/twin-suns-better-than-one/