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Post by af4ex on Mar 23, 2011 4:03:25 GMT
heather> ... when you are monitoring the sunspots, what are you looking at? We're primarily interested in the solar magnetic activity cycle (aka "solar cycle" or "solar activity"), which are periodic changes in the sun's radiation due to various magnetic processes happening inside the sun. The main cycle has a period of 11 years, but there are others, most of which are not completely understood. Right now we're in the burgeoning phase of Solar Cycle 24, seeing a lot of solar activity (sunspots and microwave flux) on a spike of activity that started around Valentine's Day. The activity spikes will probably go up and down until SC24 peaks, maybe in 2012. en.wikipedia.org/wiki/Solar_variationen.wikipedia.org/wiki/Solar_cycleMany of us at this site are ham radio operators, who are interested in radio propagation in the HF Band (3MHz-30Mhz), which is strongly affected by the 11-year cycle. At the peak of the cycle, world-wide HF communication is possible up to 30 MHz. At the cycle minimum, communication is more restricted to lower frequencies. So, we're enthusiastic about big flares and geomagnetic storms, as hams, because they tend to stir up propagation conditions. (Whereas other folks might view these events as 'bad news'). ;D There is also speculation that solar cycle variations have something to do with climate change, but these theories are fiercely debated. (We tend to steer clear of those issues in this forum). This cycle is also interesting because it seems to be one of the smallest magnitude cycles in about a hundred years. Other than that, it's hard to explain exactly why we're so nutty about the sun. 
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Post by maundalt on Mar 23, 2011 15:58:49 GMT
heather> ... when you are monitoring the sunspots, what are you looking at? We're primarily interested in the solar magnetic activity cycle (or "solar cycle" or "solar activity"), which are periodic changes in the sun's radiation due to various magnetic processes happening inside the sun. The main cycle has a period of 11 years, but there are others, most of which are not completely understood. Right now we're in the burgeoning phase of Solar Cycle 24, seeing a lot of solar activity (sunspots and microwave flux) on a spike of activity that started around Valentine's Day. The activty spikes will probably go up and down until SC24 peaks, maybe in 2012. en.wikipedia.org/wiki/Solar_variationen.wikipedia.org/wiki/Solar_cycleMany of us at this site are ham radio operators, who are interested in radio propagation in the HF Band (3MHz-30Mhz), which is strongly affected by the 11-year cycle. At the peak of the cycle, world-wide HF communication is possible up to 30 MHz. At the cycle minimum, communication is more restricted to lower frequencies. So, we're enthusiastic about big flares and geomagnetic storms, as hams, because they tend to stir up propagation conditions. (Whereas other folks might view these events as 'bad news'). ;D There is also speculation that solar cycle variations have something to do with climate change, but these theories are fiercely debated. (We tend to steer clear of those issues in this forum). This cycle is also interesting because it seems to be one of the smallest cycles in about a hundred years. Other than that, it's hard to explain exactly why we're so nutty about the sun. Also, some people are interested in a solar minimum in a similar way to how ham radio operators are interested in a solar maximum. It is an interesting scientific endeavor to learn what happens in a solar minimum. Also, there are some (mostly on other forums, though a few such as myself have leaked over to this forum) who would greatly enjoy a few of the debatable effects of a solar minimum (such as the negative Arctic Oscillation... which is a little more solidly defined than a few other, more controversial effects [NASA did an article on the Maunder around 10 years ago that mentioned the AO]). |
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Post by THEO BAKALEXIS on Mar 23, 2011 21:36:47 GMT
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bradk
Level 3 Rank
Posts: 199
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Post by bradk on Mar 24, 2011 2:01:07 GMT
VERY equatorial spots gentlemen...
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Post by af4ex on Mar 24, 2011 2:05:38 GMT
Look at the elongated umbral region (green circle) in 1176. Normally the umbras are roughly circular shaped, which is probably a stable or energy minimizing configuration. So it's amazing that this Neptune-sized 'grand canyon' is stable enough to even exist for a few minutes. How is this possible? Or is the physical reality here much different than it appears optically in visible light? (i.e. some kind of optical illusion?) Attachments:
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Post by heather on Mar 24, 2011 4:18:46 GMT
thank you! I never knew that  would you all have other sites i can dig into to read more about? to save you all from me ;D |
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Post by Bob k6tr on Mar 24, 2011 4:52:05 GMT
thank you! I never knew that would you all have other sites i can dig into to read more about? to save you all from me ;D Not much in the way of Heliophysics Basics but a great deal of info www.solen.info/solar |
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Post by sergiof on Mar 24, 2011 18:25:46 GMT
Dear fellows
By now it is posible to "predict" that the former prediction on the present sunspot and solar flux, see the graphs, is no longer an accurate estimative of this solar cycle. Once I brought here a question about the meaning of such phenomena, raising the question on wether the present low activity would represent an accumulation of energy in the Sun, energy that will have to be release sooner or latter.
Now, I raise another question on astronomic cycles. We know that we live in accordance with a conjunction of cycles, the most known: day-night, seasons and the solar cycles. But how long, in Earth years please, it takes to the Sun to perform a complete turn in Via Lactea?
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Post by af4ex on Mar 24, 2011 18:52:41 GMT
sergiof> ... raising the question on wether the present low activity would > represent an accumulation of energy in the Sun, energy that > will have to be release sooner or latter. ... I think you're suggesting that solar activity is like tectonic stress on Earth. Tension builds up and is released eventually as earthquakes. Actually, the sun's surfaces are too 'slippery' for that. There are virtually no shear forces. In fact, the opposite action occurs, different parts of the sphere slide over each other all the time, causing different parts to rotate at different angular speeds. This gets the magnetic flux tubes all tangled up (like an 'overwound' model airplane rubber band motor). The 'knots' eventually protrude above as sunspots. There is a periodic rhythm to this, which makes up the main part of the solar magnetic activity cycle, every 11 years or so. > But how long, in Earth years please, it takes to the Sun to > perform a complete turn in Via Lactea? It takes exactly one "galactic year"! "The Sun orbits around the center of the galaxy in a galactic year—once every 225-250 million Earth years." en.wikipedia.org/wiki/Milky_Way:-|
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Post by justmeanu on Mar 24, 2011 19:54:10 GMT
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Post by sergiof on Mar 24, 2011 20:07:47 GMT
sergiof> ... raising the question on wether the present low activity would > represent an accumulation of energy in the Sun, energy that > will have to be release sooner or latter. ... I think you're suggesting that solar activity is like tectonic stress on Earth. Tension builds up and is released eventually as earthquakes. Actually, the sun's surfaces are too 'slippery' for that. There are virtually no shear forces. In fact, the opposite problem occurs, different parts of the sphere slide over each other all the time, causing different parts to rotate at different angular speeds. This gets the magnetic flux tubes all tangled up (like an 'overwound' model airplane rubber band motor). The 'knots' eventually protrude above as sunspots. There is a periodic rhythm to this, which makes up the main part of the solar magnetic activity cycle, every 11 years or so. > But how long, in Earth years please, it takes to the Sun to > perform a complete turn in Via Lactea? It takes exactly one "galactic year"! "The Sun orbits around the center of the galaxy in a galactic year—once every 225-250 million Earth years." en.wikipedia.org/wiki/Milky_Way:-| Thanks for your clear and clarifying answer. |
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Post by af4ex on Mar 25, 2011 11:03:15 GMT
Looks like GOES 15 had some kind of malfunction this morning and missed a very energetic XRAY event around 0610Z. Fortunately it happened while the sun was still above the horizon at Nobeyama, which got a good snapshot of the event, just minutes before microwave sunset. solar.nro.nao.ac.jp/norh/html/10mins/2011/03/25/movie.htmlI'm guessing it was an M-Class flare because it shows up on the correlating 34GHz light curve, which is normally flat for lower energy flares. Attachments:
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Post by af4ex on Mar 25, 2011 11:25:06 GMT
... here's a movie clip of the missed flare in 094A light. Note that 1176 had been pitching numerous smaller flares all night. The 'missing' XRAY flare is the last one in the sequence, a big one: SDO/AIA 094A 2011-03-25 0615 UTC  |
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Post by THEO BAKALEXIS on Mar 25, 2011 19:35:58 GMT
Report from the region 11176 today. Only a few C-class flares inside region 11176 early in the morning. The link of the HQ video in down of the first video. Press the HQ. www.solar-007.eu/site/ |
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Post by af4ex on Mar 26, 2011 12:40:33 GMT
I claim that there were two M-Class XRAY flares yesterday, 25 Mar. The first occurred around 0610Z and the second around 2330Z. Only the second flare was reported by NOAA because their x-ray sensors were not functioning for the first event. NOAA reported a two-minute "////" outage from 0608 to 0610, but the outage looks bigger judging from the size of the gap in the 1-8A plot. www.swpc.noaa.gov/ftpdir/indices/events/20110325events.txt The 0610Z event appears to have higher intensity (but shorter duration) than the second event, judging from the Nobeyama 17GHz/34GHz plots (below) for 25 Mar (recorded in two pieces because it spanned two operational days). Couldn't find any x-ray imagery depicting the earlier blast. Even the SDO soft-xray animation skipped it (or hadn't been posted yet). :-| Attachments:
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