Questions tagged [sunspots]

Questions regarding the darker areas on the solar disk formed by emerging magnetic fields.

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Help finding a database or analysis of plage regions on the Sun

Plages are phenomena of stellar activity. A plage is a bright region in the chromosphere of the Sun, typically found in and around active regions. The term itself is poetically taken from the French ...
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What do "P" and "F" mean in the compass legend of Carrington's sunspot drawing?

In Richard Carrington's drawing of sunspots, he has a compass labeled "N", "P", "S", and "F". If "N" is North and "S" is South, what do &...
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What are Ellerman bombs and how can we identify them?

Have you ever heard about Ellerman bombs? Spaceweather.com talks about them on their news page. You could see some of them around sunspot AR2835: Ellerman bombs are magnetic explosions about one-...
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Why do sunspot rise in number "precisely" every eleven years?

Every eleven years (more or less precisely) sunspots are seen to rise in numbers. The magnetic field of the sun changes polarity over eleven years and this is the reason the number of spots can vary. ...
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Why is the 11 yr sunspot cycle less predictable recently?

I quoted from a similar question on solar minima and maxima. "...I guess the jury is still out, but this is quite "fringe" material. The solar cycle is certainly thought to be a product ...
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8 votes
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Wilson effect: How "deep" are sunspots?

I recently learned about the Wilson effect of the Sun's atmosphere. The 2009 Saas Fee Advanced Course 39 states: Near the solar limb, the umbra [the circular dark region of a sunspot] and the centre-...
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Are sunspots named or individually tracked?

This is a follow-up question to How are the solar flares from May 23, 2021 extraordinary? which is about news of spaceweather.org. In the present question, I am curious solely about sun-spots and why ...
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How are the solar flares from May 23, 2021 extraordinary?

The Space Weather News for May 23, 2021 reads (with some highlighting by me) Yesterday, the sun produced a sequence of solar flares unlike anything we've seen in years movie. Earth-orbiting ...
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Why can't stars be multicolored like gas giants?

Gas giants like Jupiter and Saturn have bands of different colors in their atmosphere. These are due to the rotation of the planets. Stars rotate too, so why do most stars have patches/blotches of ...
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Sun (star) spots (size)

My question is about sunspots size. Does these spots have a 'typical' size for all kinds of stars (dwarves or super giants), or are they dependent on a star size? In another words, is the statement ...
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Density of a sunspot compared to the surrounding photosphere?

Is the density of a sunspot different by more than a factor of ten compared to the area surrounding the sunspot?
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4 votes
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Is there a database of past sunspots?

I would like to plot a butterfly diagram. I've been looking through the SOHO archive for a table that would indicate the date and position of each sunspot, but to no avail. The closest I got was to ...
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6 votes
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Can we see evidence of sunspots on other stars? (starspots)

Searching for exoplanets by measuring the change of a stars brightness when an exoplanet transits the star's disk also has the potential to detect exo-sunspots (starspots). Have they ever been ...
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Could Tabby's star be beamed by a neutron star's jet causing irregular star spots?

There have been some other questions here about what might cause the light curve dips of star KIC 8462852 as observed by Kepler Space Telescope. Here's one I haven't heard before: Could it be that a ...
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Is the longitude assigned to sunspots spherical or projected?

Sunspot maps are created from a projection of the sun, so the coordinates of sunspots (or active regions in general) are assigned according to it. Do these coordinates correspond to actual spherical ...
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Why do sunspots appear dark?

Sunspots, such as this one, appear dark: Why?
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