Talk:Sunspot

Solar cycle

It would be nice if people who contributed to this page could also help with the solar cycle (and solar maximum/solar minimum, etc... pages), which really need some extra information. USferdinand 03:13, 16 January 2007 (UTC)

This line: "...and while the observation of a reverse polarity sunspot on 4 January 2008 officially began Cycle 24, no additional sunspots have yet been seen in this cycle." Needs to be updated now that additional sunspots have been sighted - but they are not the right polarity for the new cycle. In light of this - and the fact that cycles do not have definite starting dates anyways - IMHO this reference to Solar Cycle 24 starting on Jan.4 should be removed. —Preceding unsigned comment added by 65.215.33.194 (talk) 15:31, 26 March 2008 (UTC)

Galileo

Galileo was blinded late in life by an eye infection; his extensive observations of sunspots were 20 years earlier. The warning against direct observation has been corrected. Dandrake 02:42, Oct 28, 2003 (UTC)

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2003 X28 Flare

I'll go ahead and update the history to include the Nov 4 2003 record-setting X28 flare. Holographic images show there's still amazing activity on the far side of the sun. We'll see in a handful of days what might sweep across the ecliptic when that part of the Sun comes back into view. SEWilco 02:10, 13 Nov 2003 (UTC) co

concnerning the sunspost story a detail review are given in wilfried schröder, das phänomen des polarlichts, darmstadt, wissenschaftliche buchgesellschaft, 1984 (revised version Bremen: 2000)

The politics of the intro

Tsk tsk, Mr. Poor. The lines you added to the Intro support your politico-scientific views; and so far as I know, what they assert is accurate. But does this really belong in the Intro, where we are trying to say succinctly what sunspots are? Dandrake 18:47, Aug 6, 2004 (UTC)

Where in the cycle

One of the most obvious questions anyone who knows just a little about sunspots might want to ask is... Where are we in the sunspot cycle at the moment?

Neither this article nor any of the references seem to address this question, since after all, anyone who's reading technical stuff about sunspots would obviously already know!

As best I can tell from the charts included in the article, we're approaching a minima; would someone who actually knows like to confirm this by adding something to the article to this effect?

Seems a fair question. I put it into the intro from one of the refs. I'm not sure if it belongs there. William M. Connolley 21:29, 7 January 2006 (UTC).

History

The last sentence in the sixth paragraph says "Even the lack of a solar corona during lunar eclipses was noted prior to 1715." Shouldn't it be solar eclipses? RWinther, January 10, 2006, 02:55 (UTC)

Date of first observation

How certian is the date, 28 BC for the Chinese first observation? Here is a source that gives 170 BC. -MrFizyx 15:31, 14 August 2006 (UTC)

• This article from the UNESCO Courier cites afew earlier observations and the 28 BC observation, looks like we should go with 4th century BC or 165 BC. -MrFizyx 15:39, 14 August 2006 (UTC)

Event of 1 September 1859

It would be nice to have some more information on this event, does it have a name? I have heard some fascinating stories about it. Maybe it even deserves its own page, after all, it is the most powerful solar flare in recorded history, it's definitely an important topic. This has major practical importance too because a repeat of this magnetude of solar flare would be devistating.Dru007 01:15, 21 October 2007 (UTC)

August 2008, no sunspot activity for the first time in over a century

Would it be appropriate to mention somewhere that August 2008 was the first month in over 100 years that no sunspot activity was recorded? —Preceding unsigned comment added by 66.245.212.66 (talk) 01:05, 3 September 2008 (UTC)

Could we see graphs like these? http://dreamofthought.blogspot.com/ (Sunspots for the last 10,000 years and more)please? —Preceding unsigned comment added by 90.59.169.175 (talk) 18:55, 14 October 2008 (UTC)

Sunspots and revolutions

William M. Connolley thinks that William James Sidis was into astrology. Sidis couldn't even listen to irrational things (like the bible). Read his biography! as I wrote in edit summary: link talks about correlation of ionization from the sun radiation on human mood etc. You can compare this with seasonal affective disorder. Lakinekaki 23:11, 31 January 2006 (UTC)

Nope, I think CarolMoore is [1], whoever she may be. Sidis is probably of historical interest; his theory is junk, because he has it the wrong way round To explain this, I may say that sun spots are rifts in the surface of the sun, exposing a lower layer. This lower layer gives less light and heat than the surface, and therefore, the more spots there are on the sun, the less heat the sun will give, and the cooler will be the climate. However, he's a useful example, so I thank you for providing him! William M. Connolley 23:19, 31 January 2006 (UTC).

Welcome!69.33.60.41

I see a quote saying "but new estimates suggest a delay until 2009" but no reference given. Is this along the lines of 'okay, there's no massive evidence of global warming this year...but just wait until next year when the sunspot cycle begins again (even though it's 2 years late by then)!' More in hope than in commonsense? —Preceding unsigned comment added by Go Away White (talk • contribs) 16:43, 19 September 2008 (UTC)

Disk viewer

I removed someone's claim that a floppy disk can be used to view the sun. Someone have a source that this is indeed safe (and preferably also that it is not an opaque material)? (SEWilco 01:47, 15 August 2006 (UTC))

No, it's not safe. They meant the floppy magnetic stuff on the inside of old-style floppy disks. Again, it's not safe and transmits dangerously high levels of infrared. Sagittarian Milky Way 21:35, 13 June 2007 (UTC)

I think that CD should be safer. Reflecting infrared is requirement for it's function. And CD's are easily available. (although it may take some time to find some without print.)

What about ultraviolet, huh? Don't do that stuff. Just get eclipse shades that cost a few dollars. They probably even give them out for free if your area's having a major eclipse. Sagittarian Milky Way 18:35, 5 November 2007 (UTC)

Regarding the second photo up: I see no reason to believe that's an actual sunspot, instead of the much more likely lens or digital chip dust-bunny. 70.61.22.110 16:05, 1 October 2007 (UTC)Ubiquitousnewt

Starspots?

Similar phenomena observed on stars other than the Sun are commonly called starspots. - do we really have the rez to see them on other stars? William M. Connolley 08:23, 28 October 2006 (UTC)

We can see changes in the brightness of other stars that are interpreted to be caused by spots. Dragons flight 19:51, 28 October 2006 (UTC)

OK, I thought it might be something like that. But the text seems misleading as written (not to mention unsourced) William M. Connolley 20:03, 28 October 2006 (UTC)

I have added Strassmeier as a source, and the already-referenced Svetlana Berdyugina's comprehensive review of methods and results contains many references to starspots in the literature. This gallery has some interesting "images" of starspots. -Wikianon (talk) 00:29, 20 February 2008 (UTC)

sunspot temperatures

I'm no expert but the listed temperatures are low compared to standard sources (e.g., Allen's astrophysical quantites; Ostlie+Carroll; Zirker) which quote 4000 K

• Not only that, but the article also says "umbra (temperatures around 2200 °C), penumbra (temperatures around 3000 °C)." Yet in the intro, it says they're between 4000 and 4500K. I'm no expert either, but I do know that there's a big difference between 3000C and 4000K... --TheSlyFox 07:48, 29 January 2007 (UTC)

Sunspots appear darker (relative to the unaffected areas of the sun) in the visible spectrum, however in the ultraviolet and higher frequency spectra they appear to be very much brighter. (Source - "The Sun" a one hour British science documentary shown on SBS television, Australia, March 18, 20:30).

This would seem to indicate that the emitted radiation has increased from the visible frequency band to a higher-energy band. This is consistent with an INCREASE in temperature. DrBob127 23:35, 19 March 2007 (UTC)

• Ok, if no-one is going to offer a differing viewpoint, then I am going to change the introduction to reflect the fact that sunspots are not cooler but in fact hotter than the surrounding area (with appropriate references of course) DrBob127 02:24, 29 March 2007 (UTC)

Ok, I was wrong, sunspots are cooler despite emitting higher energy radiation. DrBob127 02:43, 29 March 2007 (UTC)

Sunspot life cycle

Is it worth mentioning the life cycle of a sunspot? I.e. that they are born at the equator and die at the poles? Jamie 10:37, 5 January 2007 (UTC)

2011-2012?

http://www.cnn.com/2007/TECH/space/04/26/solar.cycle.ap/index.html

potentially affecting airline flights, communications satellites and electrical transmissions.

can it happen what the article says? Phu2734 11:44, 28 April 2007 (UTC)

Recent info NOAA

http://www.magazine.noaa.gov/stories/mag227.htm

Very informative. Answers to a lot of these questions

Removed from "Significant events"

I've removed the following from "Significant events":

In August 2008, a NOAA observatory reported only a half-sunspot, and another reported zero sunspots. The former had not happened in fifty years, and the latter in a hundred.

The reference was Sun Makes History: First Spotless Month in a Century (DailyTech).

It isn't that significant, really--the rate of sunspot production varies naturally over long periods of time. There were five sunspot groups in October, and four of these were from Cycle 24. This is uncharacteristic of recent cycle transitions but not a significant deviation from normal, according to David Hathaway of NASA [2]. --82.18.14.143 (talk) 09:46, 12 November 2008 (UTC)