#31
|
|||
|
|||
Huge Sunspots
http://www.sec.noaa.gov/today.html
Looks like that one went "past" the X portion of the scale http://www.sec.noaa.gov/rt_plots/xray_1m.html |
#32
|
|||
|
|||
Huge Sunspots
wrote in message news http://www.sec.noaa.gov/today.html Looks like that one went "past" the X portion of the scale http://www.sec.noaa.gov/rt_plots/xray_1m.html http://www.lmsal.com/solarsoft/last_events/ |
#33
|
|||
|
|||
Huge Sunspots
wrote in message news http://www.sec.noaa.gov/today.html Looks like that one went "past" the X portion of the scale http://www.sec.noaa.gov/rt_plots/xray_1m.html http://www.lmsal.com/solarsoft/last_events/ |
#34
|
|||
|
|||
Huge Sunspots
Bob posted:
Looks like that one went "past" the X portion of the scale There are several classes of solar events which are rated in terms of their X-ray output as well as their size (from the article OBSERVING THE SUN IN H-ALPHA on the Prairie Astronomy Club's website): Solar flares are ranked in importance by optical, X-ray, or radio flux. Soft X-ray intensity is measured in the 1-8 Angstrom range monitored by the GOES weather satellites. The classes are designated by the letters Bn (n x 10-7 w/m2), Cn (n x 10-6 w/m2), Mn (n x 10-5 w/m2), or Xn (n x 10-4 w/m2), where n is the integer for each power of ten. Thus a flare classed as M3 would produce a soft X-ray flux of .00003 watts per square meter. Optically, flares are ranked by the area in square degrees of heliocentric latitude they take up on the disk. A square degree at the center of the solar disk is 12,147 km on a side, or at the sun's mean distance, each side of the square would be about 17 seconds of arc across. The optical class ranges from S (subflares) to 4 (largest). AREA (sqr. deg) OPTICAL CLASS TYPICAL SOFT X-RAY CLASS 2.0 or less S (subflares) C2 2.1-5.1 1 M3 5.2-12.4 2 X1 12.5-24.7 3 X5 More than 24.7 4 X9 *A suffix (f, n, b) is added if the brightness is faint, normal, or bright, based on a visual estimate. This last flare was X17, so its X-ray output at peak was about 17 x 10^-4 watts per square meter, which is quite large (probably one of the largest seen during this cycle). Again, some of the more impressive solar flares tend to occur in the post-maximum part of the cycle. Clear skies to you. -- David W. Knisely Prairie Astronomy Club: http://www.prairieastronomyclub.org Hyde Memorial Observatory: http://www.hydeobservatory.info/ ********************************************** * Attend the 11th Annual NEBRASKA STAR PARTY * * July 18-23, 2004, Merritt Reservoir * * http://www.NebraskaStarParty.org * ********************************************** |
#35
|
|||
|
|||
Huge Sunspots
Bob posted:
Looks like that one went "past" the X portion of the scale There are several classes of solar events which are rated in terms of their X-ray output as well as their size (from the article OBSERVING THE SUN IN H-ALPHA on the Prairie Astronomy Club's website): Solar flares are ranked in importance by optical, X-ray, or radio flux. Soft X-ray intensity is measured in the 1-8 Angstrom range monitored by the GOES weather satellites. The classes are designated by the letters Bn (n x 10-7 w/m2), Cn (n x 10-6 w/m2), Mn (n x 10-5 w/m2), or Xn (n x 10-4 w/m2), where n is the integer for each power of ten. Thus a flare classed as M3 would produce a soft X-ray flux of .00003 watts per square meter. Optically, flares are ranked by the area in square degrees of heliocentric latitude they take up on the disk. A square degree at the center of the solar disk is 12,147 km on a side, or at the sun's mean distance, each side of the square would be about 17 seconds of arc across. The optical class ranges from S (subflares) to 4 (largest). AREA (sqr. deg) OPTICAL CLASS TYPICAL SOFT X-RAY CLASS 2.0 or less S (subflares) C2 2.1-5.1 1 M3 5.2-12.4 2 X1 12.5-24.7 3 X5 More than 24.7 4 X9 *A suffix (f, n, b) is added if the brightness is faint, normal, or bright, based on a visual estimate. This last flare was X17, so its X-ray output at peak was about 17 x 10^-4 watts per square meter, which is quite large (probably one of the largest seen during this cycle). Again, some of the more impressive solar flares tend to occur in the post-maximum part of the cycle. Clear skies to you. -- David W. Knisely Prairie Astronomy Club: http://www.prairieastronomyclub.org Hyde Memorial Observatory: http://www.hydeobservatory.info/ ********************************************** * Attend the 11th Annual NEBRASKA STAR PARTY * * July 18-23, 2004, Merritt Reservoir * * http://www.NebraskaStarParty.org * ********************************************** |
#36
|
|||
|
|||
Huge Sunspots
Martin wrote:
This latest appearance, the ring (or horseshoe), seems to reinforce my unexpected conclusion that sunspots/groups are far less stable than they were 2 or 3 years ago - they develope and fade with greater rapidity. They are and they aren't. Active regions can have lifetimes measured anywhere from days to over a month. Typically, they do not last much more than one solar rotation, although a few large ones have lasted longer. These Gamma-Delta groups are known for their activity and are the frequent site of major solar flares. The "ring" which you have seen is merely an odd-form of group and not necessarily indicative of life span or spot stability. If you want to know more about how active regions develop, you might want to read the article OBSERVING THE SUN IN H-ALPHA on the website of the Prairie Astronomy Club (see URL below). Clear skies to you. -- David W. Knisely Prairie Astronomy Club: http://www.prairieastronomyclub.org Hyde Memorial Observatory: http://www.hydeobservatory.info/ ********************************************** * Attend the 11th Annual NEBRASKA STAR PARTY * * July 18-23, 2004, Merritt Reservoir * * http://www.NebraskaStarParty.org * ********************************************** |
#37
|
|||
|
|||
Huge Sunspots
Martin wrote:
This latest appearance, the ring (or horseshoe), seems to reinforce my unexpected conclusion that sunspots/groups are far less stable than they were 2 or 3 years ago - they develope and fade with greater rapidity. They are and they aren't. Active regions can have lifetimes measured anywhere from days to over a month. Typically, they do not last much more than one solar rotation, although a few large ones have lasted longer. These Gamma-Delta groups are known for their activity and are the frequent site of major solar flares. The "ring" which you have seen is merely an odd-form of group and not necessarily indicative of life span or spot stability. If you want to know more about how active regions develop, you might want to read the article OBSERVING THE SUN IN H-ALPHA on the website of the Prairie Astronomy Club (see URL below). Clear skies to you. -- David W. Knisely Prairie Astronomy Club: http://www.prairieastronomyclub.org Hyde Memorial Observatory: http://www.hydeobservatory.info/ ********************************************** * Attend the 11th Annual NEBRASKA STAR PARTY * * July 18-23, 2004, Merritt Reservoir * * http://www.NebraskaStarParty.org * ********************************************** |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
how long does the sunspots stay? | md | Amateur Astronomy | 5 | July 27th 04 02:10 AM |
Turkey, Football, Stuffing and Sunspots. . . | Howard Lester | Amateur Astronomy | 0 | November 25th 03 03:19 PM |
SWAN observes fading sunspots on the back side of the Sun (Forwarded) | Andrew Yee | Astronomy Misc | 0 | November 19th 03 10:33 PM |
SWAN Observes Fading Sunspots On The Back Side Of The Sun | Ron Baalke | Science | 0 | November 19th 03 09:11 PM |