Chapter 1: Introduction to Tabby's Star

Have you ever wondered what occurs when a massive planet, akin to Jupiter, transits in front of its host star? If you track the light emitted by that star, you would observe a decrease in its brightness—typically around 1%. This method, known as Transit Photometry, is a prevalent technique employed by scientists to detect new exoplanets. The Kepler Space Telescope utilized this method to survey the sky for such celestial bodies, observing the light curves of 100,000 stars within specific regions of the Cygnus and Lyra constellations. Based on the findings from the Kepler mission, the Planet Hunters Project identified a star exhibiting an astonishing 22% reduction in brightness.

An Unprecedented Discovery

One might ask: if a planet the size of Jupiter can only diminish a star's brightness by 1%, what could account for such a dramatic 22% reduction? This implies the object causing the dip is at least 1,000 times larger than Earth. The astronomical community was left bewildered by this unprecedented observation.

What makes this discovery even more fascinating is that it was made not by seasoned professionals, but by citizen scientists involved in the Planet Hunters Project.

The Groundbreaking Announcement

In 2015, Tabetha Boyajian, a leading astronomer for the Planet Hunters Project, published a research paper detailing these fluctuations, intriguingly titled "WTF: Where's the Flux?"—a nod to the missing flux of the star. This announcement sent shockwaves through the astronomy community, prompting a wave of global investigations.

Chapter 2: The Peculiar Nature of KIC 8462852

The star known as KIC 8462852, or Tabby's Star, is located in the Cygnus constellation, approximately 1,470 light-years away. This binary star system comprises an F-type main-sequence star and a red dwarf companion, first documented in 1890. The unusual characteristics of this star stem from not only the substantial dip in luminosity but also from its aperiodic fluctuations that manifest sporadically. After the initial dimming observed in 2009, Tabby's Star displayed normal brightness for two years before experiencing another significant drop of 15% in March 2011.

The odd behavior of Tabby's Star didn't stop there. In February 2013, the star exhibited an erratic pattern, with a complex dimming event lasting 100 days and multiple dimming occurrences. These dimming events showed varying percentages and durations, marking the longest such event recorded in modern astronomy.

Understanding the Dimming Phenomena

Astronomers have noted that the asymmetrical nature of the luminosity dips sets Tabby's Star apart from other celestial bodies. While several stars exhibit notable dimming, they often belong to a class of young stellar objects with distinct dimming characteristics, unlike those of Tabby's Star.

Chapter 3: Theories and Explanations for the Anomalies

The substantial luminosity dips of Tabby's Star have ignited a plethora of theories among astronomers. These hypotheses must be testable, falsifiable, and simple while explaining the data and making predictions. Here are some possible explanations for the star's unique behavior:

1. Protoplanetary Disk: This theory suggests that a disk of material surrounding a young star could account for the varied density and composition of dust, leading to the unusual dimming. However, Tabby's Star is too old for this model to apply effectively.
2. Catastrophic Collision: A significant impact between celestial bodies could generate debris that obstructs the star's light. Yet, this model also lacks supporting infrared emissions in observational data.
3. Dusty Comet Swarm: The gravitational influence of Tabby's red dwarf companion could dislodge comets from a surrounding Oort-like cloud, creating a swarm that intermittently blocks the star's light.
4. Orphaned Exomoons: Gaseous moons that have lost their orbit could pass in front of Tabby's Star, leading to notable dimming events.
5. Intrinsic Luminosity Variations: Changes within the star itself might be responsible for the observed brightness fluctuations, suggesting the cause may lie internally rather than externally.

The Alien Hypothesis

One of the more sensational theories posits that an advanced extraterrestrial civilization could have constructed a vast structure—known as a Dyson Swarm—designed to capture energy from their star, resulting in the unusual dimming of Tabby's Star. While this idea has captured public imagination, many scientists remain skeptical.

The interest in the potential alien connection has led to numerous investigations, including attempts by the Search for Extraterrestrial Intelligence (SETI) to detect radio signals from alien life, though no conclusive evidence has been found so far.

Chapter 4: Conclusion

The quest to unravel the mysteries surrounding Tabby's Star serves as a reminder of the vast unknowns within our universe. Despite our collective knowledge and technological advances, this peculiar star continues to elude definitive explanation. As we delve deeper into its enigmas, we may uncover new insights that challenge our understanding of the cosmos.

I invite you to share your thoughts on the various hypotheses surrounding Tabby's Star. If citizen scientists can contribute to such groundbreaking discoveries, perhaps someone among you might help solve one of the greatest mysteries in astrophysics. Stay curious and continue to ask intriguing questions.

Sources:

Boyajian, T. S., et al. (2015). "Where's the Flux?" Monthly Notices of the Royal Astronomical Society.

Wright, J. T., et al. (2016). "The Search for Extraterrestrial Civilizations with Large Energy Supplies." The Astrophysical Journal.

Ballesteros, F. J., et al. (2017). "A Possible Explanation for the Dimming of KIC 8462852." Astronomy & Astrophysics.

Montet, B. T., & Simon, J. D. (2016). "KIC 8462852 Faded Throughout the Kepler Mission." The Astrophysical Journal.

Boyajian, T. (2016, March). The most mysterious star in the universe [Video]. TED Conferences.