Yale Astronomers Develop New Way To Find Planets In Alpha Centauri

Yale astronomers have recently discovered a new way to locate habitable planets in the Alpha Centauri Star System.

Alpha Centauri
Image source: YouTube Video Screenshot

Alpha Centauri

A study in the Astronomical Journal authored by Professor Debra Fischer and graduate student Lily Zhao states that there may be small planets similar to Earth in nearby Alpha Centauri that have previously been overlooked. Additionally, the study disproved the existence of several larger planets that were theorized to exist.

SpaceDaily reports Fischer’s elaboration on this exciting new find:

“The universe has told us the most common types of planets are small planets, and our study shows these are exactly the ones that are most likely to be orbiting Alpha Centauri A and B…Because Alpha Centauri is so close, it is our first stop outside our solar system. There’s almost certain to be small, rocky planets around Alpha Centauri A and B.”

Assisting Fischer and Zhao in the study were John Brewer and Matt Giguere from Yale and Barbara Rojas-Ayala of Universidad Andres Bello in Chile.

The Alpha Centauri star system is located roughly 24.9 trillion miles away from Earth, which is an incredible distance. Despite the huge amount of space separating us, it’s the closest neighboring system to our own, making it easier to study than those even further away. The three stars in Alpha Centauri are Centauri A, Centauri B, and Proxima Centauri. A discovery of an Earth-like planet orbiting Proxima Centauri last year sparked a renewed interest in the system.

These most recent findings are from new and more advanced spectrographic instruments located in Chile. “The precision of our instruments hasn’t been good enough, until now,” said Fischer.

New Planets

Based on the equipment available previously, it was very reasonable to expect that even if there was a small planet, it would be next to impossible to detect. Zhao, the lead author of the paper, determined that there was a possibility that there are planets orbiting the three stars in Alpha Centauri. For Alpha Centauri A, planets smaller than 50 earth masses could be in orbit. For Alpha Centauri, that measurement is eight earth masses, with Proxima Centauri possibly having orbiting planets that are less than one-half of Earth’s mass.

As mentioned above, the study also eliminated the possibility for there to be larger planets in the star system. This information suggests that Jupiter-sized planets are not causing asteroids that could hit and change the orbits of smaller planets.

Zhao spoke on the implications of this research and asserted the importance of continuing research into this nearby star system.

“This is a very green study in that it recycles existing data to draw new conclusions…By using the data in a different way, we are able to rule out large planets that could endanger small, habitable worlds and narrow down the search area for future investigations.”

The information from this recent study will assist astronomers in their efforts to detect new planets in the system. The new spectrographic technology used to obtain this knowledge is also under continual development by the research team. With further advancements, we may be able to peer deeper into the world of Alpha Centauri — perhaps finding a world not unlike our own.