Having a uniform disk diameter of 57±5 mas, it is thought to be the extrasolar star with the largest apparent size as viewed from Earth.

[12] It is classified as a semiregular variable star of type SRb, indicating giants with slow poorly-defined variations, often alternating between periodic and irregular brightness changes.

[14] The star was discovered to be variable in 1874 by Benjamin Gould, and received the variable-star designation R Doradus.

The angular diameter and bolometric flux of R Doradus derive a cool surface effective temperature of 2,710±170 K.[7] Comparison of its properties with theoretical evolutionary tracks gives an age of between 6 and 14 billion years.

[8] Using ALMA facilities, researchers at Chalmers University, in July to August 2023, were able to record the movement of hot gas bubbles on the surface of the star.

Such bubbles, witness of the convective activity linked to deep nuclear fusion, would have a life of about a month, and a size more than 75 times that of the Sun.