How supersized a supergiant star is

[lpetrich]

Scientists reveal atmosphere of supergiant Antares | Space

Using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile and the National Science Foundation's Karl G. Jansky Very Large Array (VLA) in New Mexico, an international team of researchers has created the most detailed radio map yet of Antares' atmosphere. In fact, this is the most detailed radio map ever created of any star other than our sun.

While Antares' diameter is about 700 times larger than the sun in visible light, this map revealed that, as seen in radio light, the star's atmosphere stretches even farther and is even more enormous. With this detailed map, the team found that Antares' chromosphere, a gaseous layer that creates a star's outer atmosphere along with its corona, stretches to 2.5 times the star's radius. For context, our sun's chromosphere only extends to 0.5% of our star's radius.

"The longer wavelengths of the VLA revealed the supergiant's atmosphere out to nearly 12 times the star's radius."
Supergiant Atmosphere of Antares Revealed by Radio Telescopes - National Radio Astronomy Observatory

The team found that Antares' chromosphere is cooler than previous optical and ultraviolet observations suggested, peaking at 6,400 degrees Fahrenheit (3,500 degrees Celsius). This is significantly cooler than our sun's chromosphere, which is almost 36,032 degrees F (20,000 degrees C).

Betelgeuse: The Eventual Supernova | Space - about observations of a similar star.

 

[Worldtraveller]

Now that IS quite interesting.

Going to have to read the paper at some point and see how much I understand.