Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from beak.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests) ID ; Sun, 2 Dec 1990 02:36:35 -0500 (EST) Message-ID: Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Sun, 2 Dec 1990 02:36:02 -0500 (EST) Subject: SPACE Digest V12 #609 SPACE Digest Volume 12 : Issue 609 Today's Topics: SOLAR TERRESTRIAL FORECAST AND REVIEW Administrivia: Submissions to the SPACE Digest/sci.space should be mailed to space+@andrew.cmu.edu. Other mail, esp. [un]subscription notices, should be sent to space-request+@andrew.cmu.edu, or, if urgent, to tm2b+@andrew.cmu.edu ---------------------------------------------------------------------- Date: Sun, 25 Nov 90 15:28:19 MST From: std_oler%HG.ULeth.CA@vma.cc.cmu.edu (Cary Oler) Subject: SOLAR TERRESTRIAL FORECAST AND REVIEW X-St-Vmsmail-To: ST%"space+@andrew.cmu.edu" /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\ Please Note: A few modifications have been made to these reports. In addition to the new 20-day solar flux forecasts, new prediction charts have been added for potential VHF DX propagation. Included with the VHF DX propagation prediction charts are SID and auroral backscatter enhancement predictions charts. Comments regarding the inclusion/removal of these new features are welcomed. In order to keep the size of these reports down, some of the extraneous information has been removed. An informational document is being prepared to aid those who are interested in understanding and using these reports in practical applications. To obtain this file, request the document "Understanding Solar Terrestrial Reports" from: "std_oler@hg.uleth.ca". /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\ --- SOLAR TERRESTRIAL FORECAST AND REVIEW --- November 24 to December 04, 1990 Report Based In-Part from Data Obtained from the Space Environment Services Center Boulder Colorado -------- SOLAR TERRESTRIAL REVIEW FOR 18 NOVEMBER TO 24 NOVEMBER. Solar activity over the last week was mostly moderate. Numerous M-class flare's occurred throughout the week. Almost all of the activity was attributed to Region 6368, which dominated the disk with its large size and magnetic complexity. Region 6368 attained a maximum size of 9,240 million square kilometers (3,610 million square miles) on 18 November, encompassing a total of 107 spots. It is a magnetically complex Beta-Gamma-Delta region. The trailer spot complex was most active and has consistently held a delta-configuration. This region was uncharacteristically inactive considering the size and magnetic complexity that it attained. No major flares occurred from this region, although warnings were issued earlier in the week regarding the potential developement of major flare activity. Region 6368 showed signs of decay on 20 November although it continued to produce a healthy barrage of C-class and occassional M-class flares. The largest flare from this region was a class M3.5/1N at 09:54 UT on 19 November. This region was believed responsible for producing a Type II sweep between 13:46 UT and 13:49 UT on 18 November. The estimated shock velocity was 1,000 km/sec. No terrestrial impacts occurred from this event. Region 6368 has continued a very gradual decay since 20 November, maintaining a complex delta configuration in the trailing spot group. It has also continued frequent subflaring with modest amounts of C-class flaring. M-class flares have dropped in frequency since 20 November. Region 6377 (S04W01) has developed rapidly over the past 24 hours and managed to produce a healthy class M3.1/1B Tenflare at 14:25 UT on 24 November. Other minor discrete radio emissions were observed from this flare. The location of this flare was at S04E04. It lasted 57 minutes, ending at 15:09 UT on 24 November. Region 6368 also managed to produce a class M1.2/SF flare at 23:46 UT on 24 November. Both of these flares produced a SID/SWF. Geomagnetic activity was unexpectedly low this week. Activity was predicted to be unsettled to active, but maintained almost exclusively quiet conditions throughout the week. Effects from a coronal hole never materialized. As well, predicted solar activity never reached anticipated levels and thus did not produce expected terrestrial impacts. Auroral activity likewise did not reach anticipated levels. Auroral activity was not visible at middle and low latitudes. Some higher latitudes spotted moderate auroral activity on 18 November, but activity dwindled as the week progressed. Radio propagation conditions were normal to above normal this week. Relatively strong and stable signals occurred throughout the week at low and middle latitudes due to the unexpectedly quiet geomagnetic and auroral activity. Some increased levels of noise were evident on 18 November due to subsiding geomagnetic activity over higher latitudes. There were numerous short wave fades (SWFs) throughout the week, all attributed to the M-class flare activity from Region 6368. None of the SWF's were intense. The majority of frequencies affected were below 10 MHz. It is not known whether the SWF's were accompanied by VHF enhancements. Ionization levels were likely not high enough to produce any significant VHF signal enhancements, although there were probably localized area's of enhanced sporadic E during these periods. As of 25 November, two additional SID/SWF's were observed. The first began at 14:12 UT and ended at 15:05 UT on 24 November. The second began at 23:30 UT and ended at 00:31 UT on 25 November. Both of these events were of low to moderate intensity and were flare-related. SHORT TERM SOLAR TERRESTRIAL FORECAST Solar activity is expected to remain mostly low with the possibility for occassional M-class flaring from departing Region 6368 and Region 6377. The Space Environment Services Center is continuing a condition YELLOW alert status for potential PCA and proton events. Region 6368 continues to sport a Beta-Gamma-Delta magnetic configuration with particular delta complexity in the trailer spot group. Probability for a major class X flare is stationary at 10% over the next two days, dropping to 5% on 27 November with the passage of Region 6368 beyond the west limb. There is a 5% probability of a major proton flare from this region. Although these probabilities are low, they warrant attention. The solar flux is expected to drop quite dramatically with the passage of Region 6368 beyond the west limb on 26 and 27 November. Geomagnetic activity is expected to remain mostly quiet until 26 November when models suggest activity should increase to unsettled levels over all latitudes with a risk of active periods over middle and high latitude regions. No significant activity or storming is expected, however. Conditions should return to quiet to unsettled levels by 28 November. Auroral activity will be dormant until near 26 November when some increase in activity may occur. Activity will remain confined to the high latitude regions where it is expected to be mostly of low intensity with possible bursts of moderate activity. Auroral activity is then expected to decline to non-visible levels on 27/28 November and remain quiet throughout the remainder of the week. HF radio propagation conditions should be quite good this week, with only a slight increase in noise and flutter expected near 26/27 November. The expected increase in geomagnetic and auroral activity should not have much of an impact on HF radio communications. So with the exception of 26 and 27 November, HF communications should be above normal on most of the other days this week. Sporadic degraded HF propagation is possible on the sunlit side of the earth due to expected persisting SIDs/SWFs caused by minor solar flaring. VHF radio propagation should remain normal this week. There is the potential for sporadic DX contacts during SID periods which are expected to occur on the sunlit hemisphere of the earth this week due to minor flaring from departing Region 6368 and Region 6377. Other than these slight possibilities, conditions will not be sufficient to provide widespread DX opportunities this week. SUMMARY OF ALL ACTIVE REGIONS VISIBLE ON THE SOLAR DISK AS OF 25 NOVEMBER Region # Location LO Area Class LL Spots Magnetic Type -------- -------- --- ---- ----- -- ----- ------------- 6368 N18W65 025 5460 FKI 23 045 BETA-GAMMA-DELTA 6372 S18W27 347 0120 HAX 02 002 ALPHA 6376 S17W82 042 0000 AXX 00 001 ALPHA 6377 S04W01 321 0540 DAI 09 030 BETA 6378 S09E11 309 0030 BXO 04 004 BETA 6379 S06E59 261 0180 CSO 06 006 BETA 6380 S07W11 331 0000 AXX 00 001 ALPHA 6381 S04E73 247 0150 HAX 02 001 ALPHA NOTES: Area is in million square kilometers. Angular extent (LL) and solar longitude (LO) are in degree's. For more information regarding the terminology used above, request the Glossary of Solar Terrestrial Terms from: "std_oler@hg.uleth.ca". H-ALPHA PLAGES WITHOUT SPOTS. LOCATIONS VALID AS OF 24:00 UT ON 24 NOVEMBER. REGION LOCATION LO COMMENTS (IF ANY) ------ -------- --- ------------------------------- 6375 N25W42 002 NONE ACTIVE REGIONS DUE TO RETURN BETWEEN 25 AND 27 NOVEMBER Region Latitude Longitude (Helio.) ------ -------- --------- 6355 N17 223 6347 S18 216 6350 S24 213 6349 S16 198 NOTES: For definitions regarding the above, request the "Glossary of Solar Terrestrial Terms" from "std_oler@hg.uleth.ca". GRAPHICAL ANALYSIS OF RECENT GEOMAGNETIC ACTIVITY - BOULDER COLORADO Cumulative Geomagnetic Activity History Peak Geomagnetic Activity during the past 87 hours _________________________________________________________________ | EXTREMELY SEVERE | | | | | VERY HIGH! | | VERY SEVERE STORM | | | | | HIGH | | SEVERE STORM | | | | | MODERATE | | MAJOR STORM | | | | | MODERATE | | MINOR STORM | | | | | LOW | | VERY ACTIVE | | | | | NONE - LOW | | ACTIVE | | | | | NONE | | UNSETTLED | * | * **| | * *| NONE | | QUIET | ***|* ******|* **|*****| NONE | | VERY QUIET |********|********|********|*****| NONE | |-------------------|--------|--------|--------|-----|------------| | Geomagnetic Field | Thu. | Fri. | Sat. | Sun.| Anomaly | | Conditions | Given in 3-hour intervals | Intensity | |_________________________________________________________________| NOTES: This graph ONLY depicts geomagnetic conditions observed at Boulder, Colorado for the past 87 hours. Conditions to the north of Boulder will generally have slightly higher activity than Boulder, while conditions to the south of Boulder will likely have lower activity than those depicted here. However, the plots should present a good approximate average of planetary geomagnetic conditions. For information regarding the interpretation and/or use of these charts, send a request for the document "Understanding Solar Terrestrial Reports" to: std_oler@hg.uleth.ca PLANETARY 10-DAY GEOMAGNETIC ACTIVITY OUTLOOK (25 NOVEMBER - 04 DECEMBER) ________________________________________________________________________ | EXTREMELY SEVERE | | | | | | | | | | | VERY HIGH! | | VERY SEVERE STORM | | | | | | | | | | | HIGH | | SEVERE STORM | | | | | | | | | | | MODERATE | | MAJOR STORM | | | | | | | | | | | MODERATE | | MINOR STORM | | | | | | | | | | | LOW | | VERY ACTIVE | | | | | | | | | | | NONE - LOW | | ACTIVE | | | | | | | | | | | NONE | | UNSETTLED | |***|***| * | | | | * | * |***| NONE | | QUIET |***|***|***|***|***|***|***|***|***|***| NONE | | VERY QUIET |***|***|***|***|***|***|***|***|***|***| NONE | |-------------------|---|---|---|---|---|---|---|---|---|---|------------| | Geomagnetic Field |Sun|Mon|Tue|Wed|Thu|Fri|Sat|Sun|Mon|Tue| Anomaly | | Conditions | Given in 8-hour intervals | Intensity | |________________________________________________________________________| NOTES: Predicted geomagnetic activity is based heavily on recurrent phenomena. Transient energetic solar events cannot be predicted reliably over periods in excess of several days. Hence, there may be some deviations from the predictions due to the unpredictable transient solar component. GRAPHICAL ANALYSIS OF SOLAR ACTIVITY OVER THE PAST 60 DAYS Cumulative Graphical Analysis of Solar Activity ____________________________________________________________ 242| | MOD. 235| F = Major Flare(s) | MOD. 227| * | MOD. 220| *** * * | MOD. 212| *** * ** * * | MOD. 205| **** * ** *** | MOD. 197| ****** *F **** * ***** | MOD. 190| **********F ******* ******* | LOW 182| * ***********F* **************** | LOW 175| ** ************F* ****************** | LOW 167| *****************F** *********************| LOW 160| ******************F*** * * *********************| LOW 152| ********************F********** **********************| LOW 145|***********************F********** * ***********************| LOW 137|***********************F************************************| LOW 130|***********************F************************************| LOW ------------------------------------------------------------ Cumulative 60 day Solar Activity Record Start Date: September 27, 1990 NOTES: Left-hand column digits represent the 10.7 cm solar radio flux obtained from Ottawa. The right-hand column describes the relative solar activity for that period based on the average number of major and minor flares that can be expected for related solar flux values. Plot lines labeled with the letter "F" represent days where at least one major flare occurred (ie. class M5 or greater flare). GRAPHICAL 20-DAY SOLAR ACTIVITY PREDICTION Solar Activity _________________________________________________________________ | 230 | | | | | | | | | | | | | | | | | | | | | | 224 | | | | | | | | | | | | | | | | | |**|**|**| | 218 | | | | | | | | | | | | | | | | |**|**|**|**| | 212 | | | | | | | | | | | | | | | | |**|**|**|**| | 206 | | | | | | | | | | | | | | | |**|**|**|**|**| | 200 | | | | | | | | | | | | |**|**|**|**|**|**|**|**| | 194 | | | | | | | | | | |**|**|**|**|**|**|**|**|**|**| | 188 | | | | | | | | | |**|**|**|**|**|**|**|**|**|**|**| | 182 | | | | | | | | |**|**|**|**|**|**|**|**|**|**|**|**| | 176 | | | | | | | |**|**|**|**|**|**|**|**|**|**|**|**|**| | 170 |**| | | | | | |**|**|**|**|**|**|**|**|**|**|**|**|**| | 164 |**| | | | | |**|**|**|**|**|**|**|**|**|**|**|**|**|**| | 158 |**|**| | | | |**|**|**|**|**|**|**|**|**|**|**|**|**|**| | 152 |**|**| | | |**|**|**|**|**|**|**|**|**|**|**|**|**|**|**| | 146 |**|**|**| |**|**|**|**|**|**|**|**|**|**|**|**|**|**|**|**| | 140 |**|**|**|**|**|**|**|**|**|**|**|**|**|**|**|**|**|**|**|**| |-----|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--| |Solar|25|26|27|28|29|30|01|02|03|04|05|06|07|08|09|10|11|12|13|14| |Flux | November | December | ----------------------------------------------------------------- HF RADIO SIGNAL PROPAGATION PREDICTIONS (25 NOVEMBER - 04 DECEMBER) High Latitude Paths ________________________________________________________ | EXTREMELY GOOD | | | | | | | | | | | | VERY GOOD | | | | | | | | | | | | GOOD | | | | | | | | | | | | FAIR |* *| | *|* *|***|***|***|***|* *| *| | POOR | * |***|** | * | | | | | * |** | | VERY POOR | | | | | | | | | | | | EXTREMELY POOR | | | | | | | | | | | |----------------|---|---|---|---|---|---|---|---|---|---| | PROPAGATION |Sun|Mon|Tue|Wed|Thu|Fri|Sat|Sun|Mon|Tue| | QUALITY | Given in 8-Hour UT Intervals | -------------------------------------------------------- Middle Latitude Paths ________________________________________________________ | EXTREMELY GOOD | | | | | | | | | | | | VERY GOOD |* *| | *|* *|***|***|***|* *|* | | | GOOD | * |***|** | * | | | | * | **|***| | FAIR | | | | | | | | | | | | POOR | | | | | | | | | | | | VERY POOR | | | | | | | | | | | | EXTREMELY POOR | | | | | | | | | | | |----------------|---|---|---|---|---|---|---|---|---|---| | PROPAGATION |Sun|Mon|Tue|Wed|Thu|Fri|Sat|Sun|Mon|Tue| | QUALITY | Given in 8-Hour UT Intervals | -------------------------------------------------------- Low Latitude Paths ________________________________________________________ | EXTREMELY GOOD | | | | | | | | | | | | VERY GOOD |***|* *|* *|***|***|***|***|***| *| *| | GOOD | | * | * | | | | | |** |** | | FAIR | | | | | | | | | | | | POOR | | | | | | | | | | | | VERY POOR | | | | | | | | | | | | EXTREMELY POOR | | | | | | | | | | | |----------------|---|---|---|---|---|---|---|---|---|---| | PROPAGATION |Sun|Mon|Tue|Wed|Thu|Fri|Sat|Sun|Mon|Tue| | QUALITY | Given in 8-Hour UT Intervals | -------------------------------------------------------- NOTES: High latitudes >= 55 degree's north latitude Middle latitudes >= 40 < 55 degree's north latitude Low latitudes < 40 degree's north latitude POTENTIAL VHF DX PROPAGATION PREDICTIONS (25 NOVEMBER - 04 DECEMBER) INCLUDES SID AND AURORAL BACKSCATTER ENHANCEMENT PREDICTIONS HIGH LATITUDES __________________________________________________ ___________________ | SIGNAL | Given in 8 hour local time intervals | | SID ENHANCEMENT | | QUALITY |Sun|Mon|Tue|Wed|Thu|Fri|Sat|Sun|Mon|Tue| |S|M|T|W|T|F|S|S|M|T| |__________|___|___|___|___|___|___|___|___|___|___| |-|-|-|-|-|-|-|-|-|-| | VERY GOOD| | | | | | | | | | | 0%|*|*|*|*|*|*|*|*|*|*| |ABOVE NORM| | | | | | | | | | | 20%|*|*|*| | | | | | | | | NORMAL|***| *| *|***|***|***|***|***| **| *| 40%| | | | | | | | | | | |BELOW NORM| |** |** | | | | | |* |** | 60%| | | | | | | | | | | | VERY POOR| | | | | | | | | | | 80%| | | | | | | | | | | | BLACKOUT| | | | | | | | | | |100%| | | | | | | | | | | |==========|===|===|===|===|===|===|===|===|===|===| |-------------------| | 100% | | | | | | | | | | |100%| | | | | | | | | | | | 80% | | | | | | | | | | | 80%| | | | | | | | | | | | 60% | | | | | | | | | | | 60%| | | | | | | | | | | | 40% | |* *|* *| | | | | | *|* *| 40%| |*|*| | | | | | |*| | 20% |***|***|***|***|***|***|***|***|***|***| 20%|*|*|*|*| | | |*|*|*| | 0% |***|***|***|***|***|***|***|***|***|***| 0%|*|*|*|*|*|*|*|*|*|*| |----------+---|---|---|---|---|---|---|---|---|---| |-|-|-|-|-|-|-|-|-|-| |CHANCE OF |Sun|Mon|Tue|Wed|Thu|Fri|Sat|Sun|Mon|Tue| |S|M|T|W|T|F|S|S|M|T| | VHF DX | Given in 8 hour local time intervals | |AURORAL BACKSCATTER| |__________|_______________________________________| |___________________| MIDDLE LATITUDES __________________________________________________ ___________________ | SIGNAL | Given in 8 hour local time intervals | | SID ENHANCEMENT | | QUALITY |Sun|Mon|Tue|Wed|Thu|Fri|Sat|Sun|Mon|Tue| |S|M|T|W|T|F|S|S|M|T| |__________|___|___|___|___|___|___|___|___|___|___| |-|-|-|-|-|-|-|-|-|-| | VERY GOOD| | | | | | | | | | | 0%|*|*|*|*|*|*|*|*|*|*| |ABOVE NORM| | | | | | | | | | | 20%|*|*|*|*|*|*|*| | | | | NORMAL|***| **| **|***|***|***|***|***|***| **| 40%|*|*| | | | | | | | | |BELOW NORM| |* |* | | | | | | |* | 60%| | | | | | | | | | | | VERY POOR| | | | | | | | | | | 80%| | | | | | | | | | | | BLACKOUT| | | | | | | | | | |100%| | | | | | | | | | | |==========|===|===|===|===|===|===|===|===|===|===| |-------------------| | 100% | | | | | | | | | | |100%| | | | | | | | | | | | 80% | | | | | | | | | | | 80%| | | | | | | | | | | | 60% | | | | | | | | | | | 60%| | | | | | | | | | | | 40% | | *| | | | | | | | | 40%| | | | | | | | | | | | 20% | **|***|***| *| *| *| *| |* *|* *| 20%| |*|*| | | | | | |*| | 0% |***|***|***|***|***|***|***|***|***|***| 0%|*|*|*|*|*|*|*|*|*|*| |----------+---|---|---|---|---|---|---|---|---|---| |-|-|-|-|-|-|-|-|-|-| |CHANCE OF |Sun|Mon|Tue|Wed|Thu|Fri|Sat|Sun|Mon|Tue| |S|M|T|W|T|F|S|S|M|T| | VHF DX | Given in 8 hour local time intervals | |AURORAL BACKSCATTER| |__________|_______________________________________| |___________________| LOW LATITUDES __________________________________________________ ___________________ | SIGNAL | Given in 8 hour local time intervals | | SID ENHANCEMENT | | QUALITY |Sun|Mon|Tue|Wed|Thu|Fri|Sat|Sun|Mon|Tue| |S|M|T|W|T|F|S|S|M|T| |__________|___|___|___|___|___|___|___|___|___|___| |-|-|-|-|-|-|-|-|-|-| | VERY GOOD| | | | | | | | | | | 0%|*|*|*|*|*|*|*|*|*|*| |ABOVE NORM| | | | | | | | | | | 20%|*|*|*|*|*|*|*| | | | | NORMAL|***|***|***|***|***|***|***|***|***|***| 40%|*|*|*| | | | | | | | |BELOW NORM| | | | | | | | | | | 60%| |*| | | | | | | | | | VERY POOR| | | | | | | | | | | 80%| | | | | | | | | | | | BLACKOUT| | | | | | | | | | |100%| | | | | | | | | | | |==========|===|===|===|===|===|===|===|===|===|===| |-------------------| | 100% | | | | | | | | | | |100%| | | | | | | | | | | | 80% | | | | | | | | | | | 80%| | | | | | | | | | | | 60% | | | | | | | | | | | 60%| | | | | | | | | | | | 40% | **| **| | | | | | | | | 40%| | | | | | | | | | | | 20% |***|***| **| **| **| **| **| | | | 20%| | | | | | | | | | | | 0% |***|***|***|***|***|***|***|***|***|***| 0%|*|*|*|*|*|*|*|*|*|*| |----------+---|---|---|---|---|---|---|---|---|---| |-|-|-|-|-|-|-|-|-|-| |CHANCE OF |Sun|Mon|Tue|Wed|Thu|Fri|Sat|Sun|Mon|Tue| |S|M|T|W|T|F|S|S|M|T| | VHF DX | Given in 8 hour local time intervals | |AURORAL BACKSCATTER| |__________|_______________________________________| |___________________| NOTES: These VHF DX prediction charts are defined for the 50 MHz to 220 MHz bands. They are based primarily on phenomena which can affect VHF DX propagation globally. They should be used only as a guide to potential DX conditions on VHF bands. Latitudinal boundaries are the same as those for the HF predictions charts. For more information, request the document "Understanding Solar Terrestrial Reports" from: "std_oler@hg.uleth.ca". AURORAL ACTIVITY PREDICTIONS (25 NOVEMBER - 04 DECEMBER) High Latitude Locations ________________________________________________________ | EXTREMELY HIGH | | | | | | | | | | | | VERY HIGH | | | | | | | | | | | | HIGH | | | | | | | | | | | | MODERATE | | * | * | | | | | | | * | | LOW | **|***|***|***| | | | * | * |***| | NOT VISIBLE |***|***|***|***|***|***|***|***|***|***| |----------------|---|---|---|---|---|---|---|---|---|---| | AURORAL |Sun|Mon|Tue|Wed|Thu|Fri|Sat|Sun|Mon|Tue| | INTENSITY | Eve.Twilight/Midnight/Morn.Twilight | -------------------------------------------------------- Middle Latitude Locations ________________________________________________________ | EXTREMELY HIGH | | | | | | | | | | | | VERY HIGH | | | | | | | | | | | | HIGH | | | | | | | | | | | | MODERATE | | | | | | | | | | | | LOW | |***|***| | | | | | * |***| | NOT VISIBLE |***|***|***|***|***|***|***|***|***|***| |----------------|---|---|---|---|---|---|---|---|---|---| | AURORAL |Sun|Mon|Tue|Wed|Thu|Fri|Sat|Sun|Mon|Tue| | INTENSITY | Eve.Twilight/Midnight/Morn.Twilight | -------------------------------------------------------- Low Latitude Locations ________________________________________________________ | EXTREMELY HIGH | | | | | | | | | | | | VERY HIGH | | | | | | | | | | | | HIGH | | | | | | | | | | | | MODERATE | | | | | | | | | | | | LOW | | | | | | | | | | | | NOT VISIBLE |***|***|***|***|***|***|***|***|***|***| |----------------|---|---|---|---|---|---|---|---|---|---| | AURORAL |Sun|Mon|Tue|Wed|Thu|Fri|Sat|Sun|Mon|Tue| | INTENSITY | Eve.Twilight/Midnight/Morn.Twilight | -------------------------------------------------------- NOTE: For more information regarding these charts, send a request for the document, "Understanding Solar Terrestrial Reports" to: std_oler@hg.uleth.ca ** End of Report ** ------------------------------ End of SPACE Digest V12 #609 *******************