By Nicole Strossman, Biochemistry and Molecular Biology, ‘17
Author’s Note:
“I decided to write this piece after seeing news headlines announcing the potential of life on planets in a nearby star system. As this is a topic that fascinates many people, myself included, I decided to investigate the new discoveries. While the research on the particular planet mentioned in the various news articles is still fairly new, it has brought about renewed interest in the search for life beyond our planet. This article aims to describe what these recent discoveries are, and show the implications they have for astronomers.”
With numerous movies, TV shows, and books in popular culture depicting fascinating stories about alien visits to Earth, it is easy to simply regard the subject of extraterrestrial life forms as science fiction. However, recent discoveries are demonstrating that ideas about life outside of Earth may not be so far-fetched.
Alpha Centauri, a star system located 4.3 light years away from our solar system, is comprised of three stars: Alpha Centauri A, Alpha Centauri B, and Proxima Centauri. Although scientists have known about this star system for centuries, the discovery in late 2016 of a planet orbiting Proxima Centauri, called Proxima b, has sparked new interest in this star system.
Proxima b, a planet similar in size to Earth, initially looked like a good candidate for life, as it is located in the habitable zone of its star, meaning that it could support liquid water. However, as research on this planet has continued, conflicting arguments have arisen about whether or not life on this planet is possible.
Proxima b orbits two class M dwarf stars, a type of red dwarf star, in contrast to our sun, which is a yellow dwarf. Although not much is known about red dwarf stars, it is thought that their habitable region is located very close to the star due to the lower temperature, thus putting the nearby planet at risk of radiation and solar flares. Consequently, some scientists argue that water and life are not probable on Proxima b.
In contrast, other scientists believe that life there is in fact possible. Simulations conducted at the Blue Marble Space Institute of Science in Seattle, Washington have demonstrated that if certain conditions are met, Proxima b could support life. For instance, if the planet has a strong magnetic field, or if past water evaporation created an oxygen-rich atmosphere, life on this planet is certainly feasible. Additionally, as red dwarfs take longer to burn out into a white dwarf than yellow dwarfs do, researchers argue that this longer lifespan allows more time for complex life to evolve.
The discovery of a potentially habitable planet has generated excitement with regards to finding more planets in the Alpha Centauri star system. Breakthrough Initiatives and the European Southern Observatory (ESO), two groups with goals to explore our vast universe, have partnered together for a project that involves studying Alpha Centauri. Both of these groups have the ultimate goal of finding intelligent life beyond Earth and are thus searching for planets that have the ability to support life, as discoveries in this area would prove to be beneficial to human civilization for a number of reasons.
Specifically, the groups will be utilizing ESO’s Very Large Telescope in Chile to examine the star system in detail, in an effort to identify any other planets in the habitable zones around the stars. Furthermore, they will continue to investigate Proxima b to learn more about whether or not life is possible.
Although these discoveries about the potential for life on other planets are different from how alien life forms are typically portrayed in movies, these recent findings breathe life into to the idea that we may not be alone in the universe.
Sources
- Billings, Lee. “A Breakthrough in the Search for Alpha Centauri’s Planets.” Scientific American. N.p., 12 Jan. 2017. Web.
- “Found! Potentially Earth-Like Planet at Proxima Centauri Is Closest Ever.” Space.com. 24 Aug. 2016. Web
- “Giant Telescope To Seek Habitable Planets in Alpha Centauri.” SciTech Today RSS. 11 Jan. 2017. Web.
- “The Nearest Alien Planet to Earth Has Three Suns.” Inverse. 22 Dec. 2016. Web.
- “New Study Says Proxima B Could Support Life.” Universe Today. 24 Dec. 2016. Web.
- “Planet Found in Habitable Zone Around Nearest Star – Pale Red Dot Campaign Reveals Earth-mass World in Orbit around Proxima Centauri.” ESO. 24 Aug. 2016. Web.
- “Red Dwarfs: The Most Common and Longest-Lived Stars.” Space.com. 21 Dec. 2016. Web.