Astronomers Discover Exoplanet Orbiting Twin Stars, Similar to Tatooine

Astronomers have made a groundbreaking discovery with the identification of an unusual exoplanet, designated HD 143811 AB b, that orbits two stars closely in a binary star system. This significant finding was detailed in a study published in the journal Astronomy & Astrophysics. The planet, located approximately 446 light-years from Earth, shares similarities with the fictional planet Tatooine from the Star Wars saga, known for its twin suns.

Researchers from Northwestern University in Chicago, Illinois, released time-lapse imagery of HD 143811 AB b orbiting its luminous twin stars, which are closer than any previously recorded binary system exoplanet. This discovery offers astronomers a rare opportunity to analyze the trajectories of both the planet and the stars within this system.

According to Jason Wang, an expert in exoplanet imaging, “Of the 6,000 exoplanets that we know of, only a very small fraction of them orbit binaries.” He emphasized the significance of capturing images of both the planet and its binary stars, stating, “It’s the only type of planetary system where we can trace both the orbit of the binary star and the planet in the sky at the same time.”

Despite its proximity to its suns, HD 143811 AB b is still about 80 times further from its light sources than Earth is from the Sun. The planet takes about 300 years to complete one orbit around its stars, which themselves orbit each other once every 18 days. Notably, this gas giant is estimated to be six times the size of Jupiter.

Surprisingly, this is not a new discovery. The planet was uncovered from archival data collected a decade ago by the Gemini South telescope and its Gemini Planet Imager (GPI). Wang and his team revisited the data gathered between 2016 and 2019, cross-referencing it with information from the W.M. Keck Observatory. Their efforts led to the identification of a faint object moving alongside a star, which indicated that it was likely an orbiting planet.

Wang remarked on the significance of their findings: “If a planet is bound to a star, then it will move with the star.” He explained that if a planet does not move with its star, it is likely just a passing star. The confirmation of HD 143811 AB b as a planet was independently verified by astronomers from the University of Exeter in the UK.

Among the intriguing characteristics of HD 143811 AB b is its temperature of approximately 1,416°F, making it nearly twice as hot as Venus. The planet is also relatively young, estimated to be around 13 million years old, particularly when compared to Earth, which formed about 4.6 billion years ago.

The formation of this exoplanet around its twin stars remains uncertain. “Exactly how it works is still uncertain,” Wang stated, noting that the rarity of such systems makes it challenging to gather enough data for a comprehensive understanding. The research team plans to continue observing the orbits of the planet and its stars to gain further insights into the interactions between binary stars and their planets.

As astronomers delve deeper into this extraordinary discovery, the potential for new knowledge about planetary systems continues to expand. The study of HD 143811 AB b not only enriches our understanding of the cosmos but also connects the realms of science and popular culture through its resemblance to the iconic Tatooine.