APOD: Sun Dance (2024 Jul 28)

[APOD Robot]

Sun Dance

Explanation: Sometimes, the surface of our Sun seems to dance. In the middle of 2012, for example, NASA's Sun-orbiting Solar Dynamic Observatory spacecraft imaged an impressive prominence that seemed to perform a running dive roll like an acrobatic dancer. The dramatic explosion was captured in ultraviolet light in the featured time-lapse video covering about three hours. A looping magnetic field directed the flow of hot plasma on the Sun. The scale of the dancing prominence is huge -- the entire Earth would easily fit under the flowing arch of hot gas. A quiescent prominence typically lasts about a month and may erupt in a Coronal Mass Ejection (CME), expelling hot gas into the Solar System. The energy mechanism that creates a solar prominence is still a topic of research. Like in 2012, this year the Sun's surface is again quite active and features many filaments and prominences.

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[Ann]

Well, the Sun dance is impressive, but...

The Sun is much more quiet than most other stars of its type!

The Sun's energy output compared to a typical similar star. Credit: MPS / hormesdesign.de

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New Atlas wrote:

To get a sense of how “normal” the Sun may be, astronomers have compared the Sun to hundreds of similar stars. It turns out that it’s actually far less active than its peers – but is this a permanent personality, or is it just going through a phase?
...
Using data from the Kepler and Gaia Space Telescopes, the team filtered the most Sun-like stars out of a catalogue of 150,000 main sequence stars. The main criterium was rotation period – the Sun rotates once every 24.5 days, so the researchers focused on stars with 20- to 30-day rotations. Then they narrowed down the list further by looking for stars with surface temperatures, ages and element ratios that most closely matched the Sun. In the end, they came up with 369 Sun-like stars to study.

To the surprise of the team, the Sun seems to be generally much quieter than most other stars. The Sun’s radiation fluctuates by just 0.07 percent between its active and inactive phases, while variations for other stars were usually five times stronger.

Perhaps the Sun's well-mannered behavior is another factor contributing to the life-friendliness of the Earth?

Ann

Oh, and... the number of posts I have right now, 13631, is a palindrome. I think.

[bls0326]

Hi Ann. Congratulations on your palindrome milestone. I have read many, many of your posts. They are quite informative and interesting!

Brian

[Ann]

Hi Ann. Congratulations on your palindrome milestone. I have read many, many of your posts. They are quite informative and interesting!

Brian

Thanks a bunch, Brian!

Ann

[johnnydeep]

It's a marvelous day for a Sun dance (with apologies to Van Morrison):

Click to play embedded YouTube video.