Giant companion candidate detected orbiting the unusual Tabby's star

Star system: KIC 8462852 A | Distance from the Sun: 1470 light years

Tabby's star, known scientifically as KIC 8462852, has long puzzled observers due to its deep, irregular dimming events. While these events were often attributed to clouds of dust from disintegrating comets or asteroids, new data from the Transiting Exoplanet Survey Satellite (TESS) show a unique, symmetric transit signature. This pattern suggests the presence of a massive object, such as a large planet or a brown dwarf, moving in front of the star.

The analysis combined TESS data with radial velocity measurements—a method that detects the slight gravitational wobble a star experiences due to an orbiting companion's pull. These calculations indicate a potential orbit lasting at least 1,030 days. Testing various models, the data fit better with the presence of a giant companion rather than clouds of cometary debris, which failed to reproduce the observations without unrealistic physical assumptions.

Preliminary estimates suggest this object has a mass approximately 9.4 times that of Jupiter and a radius of 1.7 times that of Jupiter. While this supports the existence of a massive companion in the border between a giant planet and a brown dwarf, current detection confidence is at 2.3 standard deviations, requiring further observation to confirm the object's identity. Future data from the Gaia satellite are expected to clarify its nature.

Key findings
- Tentative evidence found for a companion orbiting Tabby's star with a period of at least 1,030 days.
- Estimated mass of the companion is 9.4 times that of Jupiter.
- Companion radius measured at 1.7 times that of Jupiter.
- Data favor a giant planet or brown dwarf model over the previous exocometary dust theory for the transit event.
- Future Gaia satellite observations will be essential for definitive classification.

Scientific study

Evidence for a giant companion orbiting Tabby's star (external link)