GSFC: Swift Observes Mega Flares from a Mini Star

[bystander]

Swift Observes Mega Flares from a Mini Star
NASA | GSFC | Swift | 2014 Sep 30

Click to play embedded YouTube video.

On April 23, NASA's Swift satellite detected the strongest, hottest, and longest-lasting sequence of stellar flares ever seen from a nearby red dwarf star. The initial blast from this record-setting series of explosions was as much as 10,000 times more powerful than the largest solar flare ever recorded.

"We used to think major flaring episodes from red dwarfs lasted no more than a day, but Swift detected at least seven powerful eruptions over a period of about two weeks," said Stephen Drake, an astrophysicist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, who gave a presentation on the "superflare" at the August meeting of the American Astronomical Society’s High Energy Astrophysics Division. "This was a very complex event."

At its peak, the flare reached temperatures of 360 million degrees Fahrenheit (200 million Celsius), more than 12 times hotter than the center of the sun. ...

Swift Detection of a Superflare from DG CVn - S. Drake et al

• The Astronomer's Telegram #6121 (05 May 2014)

[Ann]

http://www.nasa.gov/content/goddard/nas ... CwX4jZhkhY wrote:
The star's brightness in visible and ultraviolet light, measured both by ground-based observatories and Swift's Optical/Ultraviolet Telescope, rose by 10 and 100 times, respectively.

This suggests that at least the initial flare was mostly blue in color! Imagine looking in the general direction of this tiny star and suddenly seeing a tremendous blue flash!

Of course, the main message of this observation is that tiny red dwarfs can be truly deadly. But I think I have heard that it is mostly young red dwarfs that behave so badly.

Ann