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Date: Fri, 25 Jan 91 09:45:20 -0500 (EST)
Subject: SPACE Digest V13 #068
SPACE Digest Volume 13 : Issue 68
Today's Topics:
MONTHLY SOLAR TERRESTRIAL REVIEW
Re: SPACE Digest V13 #029
Administrivia:
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----------------------------------------------------------------------
Date: Fri, 18 Jan 91 20:46:01 MST
From: std_oler%HG.ULeth.CA@vma.cc.cmu.edu (Cary Oler)
Subject: MONTHLY SOLAR TERRESTRIAL REVIEW
X-St-Vmsmail-To: ST%"space+@andrew.cmu.edu"
--- MONTHLY SOLAR TERRESTRIAL REVIEW ---
December 1990
Report Issued In-Part from Data Released by the
Space Environment Services Center
Boulder Colorado
--------
MONTHLY ACTIVITY SUMMARY AND SOLAR CYCLE OUTLOOK JANUARY 1991 - JULY 1991
We are now in month 52 of solar cycle 22. Activity levels made a
dramatic increase in December when compared to the last several months.
There were a total of 53 energetic events (M1 flares or greater), nine of
these were major flares (M5 or greater) and of these nine, three reached X
flare classification. To put this in perspective, in November, there were 25
energetic events, only one was a major flare. This is the first X-class
activity since August 1990, when just one event occurred. In response, solar
indices were also up, nearly 10% over November levels. Although this is a
substantial increase, indices would have to remain at this level for a number
of months to unseat July 1989 as solar maximum. This scenario seems unlikely
at this time.
Region 6412 was one of the most prolific flare producers of this month.
Eight energetic events, including two X-class flares, an X1/2B Tenflare at
09:52 UT on 23 December and an X1/1B Tenflare at 15:41 UT on 24 December were
attributed to this region. Region 6412 was the return of old Region 6368
described in Novembers summary as the second largest region of this solar
cycle. Although Region 6412 was only about one third the size of last
rotation, magnetic complexity and gradients increased this rotation, hence the
flare activity. Another major contributor to this month's activity was
Region 6420. It produced 10 energetic events including an X1/2B Tenflare at
14:02 UT on 26 December. This region never attained very large proportions,
but it was a member of a complex of regions, and interaction with these
regions may have contributed to Region 6420's flare production. Satellite
level protons became enhanced at 18:50 UT on 24 December and peaked at 3 pfu
(particle flux units) at greater than 10 MeV at 20:35 UT on 24 December.
This activity was most likely in response to the X1/1B Tenflare which
occurred about four hours earlier. Proton levels remained slightly enhanced
until early on 26 December. The geomagnetic field was quiet to unsettled
throughout the month, with the exception of three days when high latitudes
experienced active conditions.
SIX MONTH SOLAR CYCLE OUTLOOK
The activity over the past month was the expected pulse that was
anticipated earlier in October and November. It occurred a bit earlier than
was expected from the models, but attained levels similar to the predictions
made by the models. Geomagnetic activity was far below levels anticipated by
models for this pulse of activity.
Prediction models are now indicating a second "maximum" in solar
activity is possible in March or April 1991. This secondary peak is not
expected to surpass the activity which occurred in July 1989, although the
activity is expected to be enhanced with a notable increase in flaring.
Also, the risk for terrestrial impacts appears to be greater with this
expected secondary peak (or at least, extended activity period) as the
earth's orbital configuration changes to permit more efficient geomagnetic
coupling during the vernal equinox. Hence, mass ejections from the sun will
have a greater impact than we have witnessed over the past several months
(assuming the models are correct).
Solar activity in January and February is expected to remain mostly low
with occassional periods of moderate activity and isolated infrequent periods
of major flaring. Activity could begin to become enhanced in late February
or sometime in March. During this next expected peak of activity, M-class
flaring will become more frequent. Background x-ray flux levels will become
enhanced and the incidence of major flares will increase (again, assuming the
models are correct). There is also an increased risk for terrestrial impacts
from proton flaring in this next peak of activity. PCA and satellite proton
events may again be observed if activity attains or surpasses levels currently
predicted.
The geomagnetic activity outlook for January and much of February looks
relatively good. Generally quiet to unsettled conditions are expected
throughout January and much of February, barring unexpected energetic solar
activity. The recurrent patterns indicate a decline in overall coronal hole
activity over the past several months. This pattern could change rapidly,
however, with the onset of a potentially energetic increase in solar activity
around March or April 1991.
Auroral activity is likewise expected to remain generally dormant
throughout January and most of February. Some isolated periods of increased
auroral activity may occur in late February or March. The general consensus
still seems to be that some significant auroral activity could occur during
this predicted peak of activity. It all depends on the extent of the
increased solar activity and how energetic it becomes. We are currently
following the models which suggest at least one potentially significant
auroral and geomagnetic storm could occur during this secondary "maximum."
Although it is still far too early to make reliable predictions regarding
the extent of the activity, the models currently project a potential storm
period sometime in March or April (or sometime thereabouts) which could
produce planetary magnetic A-index values of between 45 and 60, with
high-latitude projections of the A-index reaching perhaps higher than 100.
These are preliminary, however and should be regarded as rough projections of
possible activity. Indeed, the magnitude of any geophysical activity is
heavily dependent on the intensity of solar activity, and the extent of the
solar activity could very well differ greatly from what has been predicted.
HF radio propagation conditions will be abnormally good during January
and much of February, possibly even spilling into March. Stable DX is
expected throughout most of January and much of February, excluding brief
periods (of a day or two) of somewhat degraded conditions due to the few
coronal holes which appear to be longer-lived. Overall, some very good DX
potential exists for January and February. March may be somewhat of a
mixed-bag for radio communications. Possibly increased solar activity during
this month could lead to increased SID/SWF occurrences, increased geomagnetic
and auroral activity and hence degraded HF stability. However, the increased
activity could push solar indices and radiation levels to values sufficient
to provide good openings on 6 meters or higher. Thus, March and April could
include numerous days of excellent HF propagation and numerous days of poor
HF propagation.
VHF propagation conditions will remain normal throughout January and
most of February with little opportunity for significant DX or auroral
backscatter. March and April, however, may herald increased potentials for
DX, particularly on the lower frequencies near 6 meters. As well, the chance
for auroral backscatter is higher during March and April than it has been for
many months. The probabilities for increased SID enhancements in March and
April are a likelihood if solar activity attains the levels currently
predicted. Hence, VHF propagation is also expected to experience days of
enhanced communications and increased DX potential, as well as days of normal
or below normal conditions in association with disturbed geomagnetic and
auroral periods during the months of March and April.
Models suggest that the predicted peak in activity expected in March or
April may be tardy by up to a month, possibly occurring in May as opposed to
March or April. However, analysis of recent activity pulses indicate that
March or April are much more likely to produce the secondary "maximum" than
the models which suggest the maximum may occur slightly later. The other
realistic option being explored is the possibility that this next secondary
maximum may in fact manifest itself as an extended period of enhanced
activity, occurring perhaps into late May or June. This is not improbable.
Such an occurrence has been observed in several previous solar cycles, most
notably solar cycle 18.
Although the probability for another peak in activity sufficiently
powerful to unseat July 1989 as "solar max" for Cycle 22 is quite low, the
possibility does still statistically exist. It should be noted that the next
few months, particularly March and/or April, represents the statistical periods
when this secondary peak could occur. It is based on the behavior of most of
the previous solar cycles. Although a pulse of activity is likely to occur
sometime near this period, the extent of the activity (if it does indeed
occur) is still uncertain. What has been reported herein is what is known
and expected at present. This could change as we approach this uncertain
statistically important period.
RECENT SOLAR INDICES (PRELIMINARY) OF THE OBSERVED MONTHLY MEAN VALUES
Updated for December, 1990
Sunspot Numbers Radio Flux Geomagnetic
------------------------------------ ------------- -----------
Observed Ratio Smooth Values Ottawa Smooth Smooth
SESC RI RI/SESC SESC RI 10 cm Value Ap Value
------------------------------------ ------------- -----------
YEAR = 1989
Jan: 203.2 161.6 .80 189.2 141.9 235.4 190.2 19 16.7
Feb: 211.0 164.5 .78 196.0 144.7 222.4 194.0 15 17.0
Mar: 176.8 131.0 .74 204.1 149.4 205.1 199.7 41 17.6
Apr: 172.3 129.3 .75 209.9 153.1 189.6 204.4 23 18.2
May: 207.0 138.4 .67 216.4 156.5 190.1 209.3 16 18.8
Jun: 297.3 196.0 .66 220.1 157.9 239.6 213.1 17 19.2
Jul: 193.9 126.8 .65 221.1 158.1 181.9 212.6 8 19.1
Aug: 243.0 166.8 .69 221.5 157.4 217.1 209.7 20 19.3
Sep: 240.7 176.8 .74 221.3 156.3 225.9 207.2 17 18.8
Oct: 217.4 158.5 .73 223.2 157.1 208.7 206.3 21 18.3
Nov: 255.0 173.0 .68 223.4 157.3 235.1 206.1 19 18.4
Dec: 217.8 166.1 .76 217.3 153.3 213.0 203.3 16 18.4
YEAR = 1990
Jan: 239.3 179.4 .75 212.4 150.3 210.1 200.4 14 18.6
Feb: 184.7 128.4 .71 213.9 152.5 178.3 200.5 23 18.8
Mar: 198.6 140.8 .71 212.7 151.7 188.8 198.7 23 18.6
Apr: 196.1 139.8 .71 210.5 149.0 185.3 195.6 27 18.2*
May: 187.7 132.0 .70 208.1 146.7* 189.7 192.3* 16 17.5*
Jun: 168.9 105.2 .62 205.3 143.4* 170.9 189.8* 16 16.7*
Jul: 204.3 147.0 .72 180.7 14
Aug: 269.4 199.9 .74 222.6 19
Sep: 186.4 124.7 .67 177.4 14
Oct: 219.0 145.2 .66 182.0 14*
Nov: 196.1 130.5* .67* 183.1* 9*
Dec: 208.0 128.5* .62* 203.8* 7*
* = Preliminary estimates
The lowest smoothed sunspot number for Cycle 21, RI = 12.3, occurred in
September 1986. The preliminary sunspot maximum for this cycle (cycle 22)
remains July 1989, with a peak smoothed sunspot number of 158.1.
DAILY SOLAR DATA FOR DECEMBER, 1990.
ENERGETIC EVENT SUMMARY (MINOR AND MAJOR FLARES)
_____________________________________________________________________________
| Date | Time (U.T.) | X-Ray | Optical Information | Sweep Freq. |
| | Begin Max End | Class | Type Location Region | Intensity |
|------|-----------------|-------|------------------------------| II III IV V|
|01 Dec| 1649 1651 1656| M1.4 | SF N19W80 6368 | | 1 | | |
|03 Dec| 1914 1924 1937| M1.0 | SN N11E66 6397 | | | | |
|04 Dec| 0157 0203 0236| M6.6 | 1F N08E56 6397 | | 2 | | |
| | 1429 1439 1507| M1.8 | 1B N08E51 6397 | | | | |
|05 Dec| 0721 0727 0803| M2.7 | 2N N08E43 6397 | | | | |
|07 Dec| 1407 1411 1417| M1.0 | 1F N09E16 6397 | | | | |
|09 Dec| 0813 0821 0918| M2.8 | 1N N02E79 6410 | | 1 | | |
| | 0922 0928 0939| M1.0 | 1F N09W11 6397 | | | | |
|10 Dec| 0654 0754 0837| M5.8 | 2B N15W47 6398 | 3 | 3 | 3| 2|
|11 Dec| 0501 0508 0529| M1.1 | SF S25W88 6387 | | 2 | | |
| | 1127 1153 1214| M1.3 | 1N N11W61 6398 | | 2 | | |
| | 1808 1819 1853| M1.3 | SF N12W66 6398 | | | | 1|
| | 2030 2052 2107| M6.5 | SB S11W80 6402 | | | | |
| | 2255 2312 2340| M1.1 | SN N13W72 6398 | | 3 | | |
|12 Dec| 0324 0328 0334| M1.7 | 1B N23W68 6399 | | | | |
| | 0336 0344 0438| M4.0 | Uncorrelated Optical Event | | 3 | | |
| | 0624 0707 0743| M1.6 | 1B N20W73 6399 | | 2 | | |
| | 0754 0803 0851| M5.1 | SF N20W73 6399 | | | | |
| | 1105 1112 1141| M1.6 | SF N19W74 6399 | 2 | | | |
| | 1401 1410 1512| M8.9 | SF N10W72 6398 | | 1 | | |
| | 1921 1939 2014| M1.6 | Uncorrelated Optical Event | | | | |
|13 Dec| 1352 1359 1413| M1.1 | 1N N03E27 6410 | | | | |
| | 1620 1630 1654| M1.5 | SF N16W78 6398 | | | | |
|14 Dec| 1116 1124 1133| M1.0 | Uncorrelated Optical Event | | | | |
| | 1331 1334 1337| M3.9 | SF N16E32 6412 | | | | |
|15 Dec| 0537 0544 0549| M1.8 | 1N N12E35 6412 | | 2 | | |
|17 Dec| 0635 0642 0650| M1.1 | 1B N14E10 6412 | | | | |
| | 1515 1529 1536| M2.4 | 1B N14E04 6412 | | | | |
|18 Dec| 0147 0155 0205| M1.8 | 1N N14W17 6415 | | 3 | | |
| | 1003 1038 1105| M1.5 | 1N N11W22 6415 | | | | |
| | 2026 2048 2109| M1.0 | SN N13W26 6415 | | | | |
|19 Dec| 0040 0146 0322| M1.1 | SF N12W30 6415 | | 1+| | |
| | 0404 0441 0538| M1.7 | SF N14W31 6415 | | 2 | | |
| | 1449 1505 1544| M3.0 | 2B N15W23 6412 | | 1 | | |
|20 Dec| 0704 0726 0801| M3.7 | 1N N14W47 6415 | 3 | 2 | | |
| | 2035 2044 2049| M1.2 | 1N N12W39 6412 | | 1+| | |
|21 Dec| 0318 0331 0420| M1.4 | Uncorrelated Optical Event | | | | |
| | 1546 1602 1615| M1.0 | SF S19E69 6420 | | 1 | | |
|22 Dec| 1537 1548 1606| M1.2 | SF S25E66 6420 | | | | |
| | 2212 2246 2311| M5.3 | 2B S25E63 6420 | | 2 | | |
| | 2313 2321 2344| M4.3 | 1N N13W87 6415 | 2 | 3 | 1| 3|
| | 2356 2358 0002| M1.4 | SB S21E55 6420 | | | | |
|23 Dec| 0933 0952 1013| X1.0 | 2B N11W68 6412 | 3 | 2 | | |
|24 Dec| 0054 0106 0126| M1.0 | SF S25E44 6420 | | | | |
| | 1319 1326 1410| M2.2 | 1F S24E47 6420 | | | | |
| | 1530 1541 1600| X1.8 | 1B N10W80 6412 | | | | 1|
| | 2238 2300 2353| M1.0 | 1F S27E39 6420 | | 1 | | |
|26 Dec| 0203 0226 0259| M1.8 | 1N S26E25 6420 | | 1 | | |
| | 1115 1128 1157| M1.7 | 1F S26E25 6420 | | | | |
| | 1356 1402 1427| X1.9 | 2B S26E21 6420 | | | | |
|30 Dec| 1315 1321 1323| M1.7 | SB S07W43 6424 | | | | |
| | 1510 1516 1520| M4.0 | 1B S09W45 6424 | | | | 3|
| | 1828 1832 1834| M1.2 | SN S09W47 6424 | | | | |
|______|_________________|_______|______________________________|___|___|__|__|
NOTES:
- Xray Flare Classes (weak to strong): C, M, X (with sub-categories rated
from 0.0 to 9.9 in each class).
- Optical Flare Classes (weak to strong): S, 1, 2, 3, 4 (with an
attached figure identifying brightness: F-Faint, N-Normal, B-Brilliant).
- Locations are given in latitude and longitude as measured from the
central solar meridian.
- Sweep Frequency Intensity represents the intensity of detected solar radio
frequency bursts (bursts sweep over large frequencies). Type II and IV
almost always represent ejection of solar material through the solar corona
and into interplanetary space. Intensities are rated from 1 to 3+.
- For more information, request the document "Understanding Solar
Terrestrial Reports" from: std_oler@hg.uleth.ca
GENERAL DAILY SOLAR STATISTICS
_____________________________________________________________________________
| | Radio Flux | | Sunspot | Flares |
| | Ottawa | Sunspot | Area | X-Ray Optical |
|Date | 10.7 cm | Number | mil.sq.km. | C M X | S 1 2 3 |
|-------|-------------|-----------|------------|--- --- --- | --- --- --- --- |
|01 Dec | 176 | 211 | 2,970 | 9 1 0 | 11 0 0 0 |
|02 Dec | 182 | 262 | 3,270 | 5 0 0 | 7 1 0 0 |
|03 Dec | 193 | 273 | 3,960 |11 1 0 | 13 0 0 0 |
|04 Dec | 203 | 284 | 4,200 |10 2 0 | 22 3 0 0 |
|05 Dec | 218 | 282 | 4,410 |11 1 0 | 32 0 1 0 |
|06 Dec | 228 | 289 | 3,510 | 5 0 0 | 15 0 0 0 |
|07 Dec | 226 | 336 | 3,270 | 6 1 0 | 17 1 0 0 |
|08 Dec | 230 | 343 | 4,410 |10 0 0 | 35 2 0 0 |
|09 Dec | 235 | 288 | 5,010 | 7 2 0 | 26 4 0 0 |
|10 Dec | 239 | 273 | 5,700 |20 1 0 | 43 1 1 0 |
|11 Dec | 239 | 242 | 6,150 |12 5 0 | 46 8 0 0 |
|12 Dec | 236 | 208 | 8,820 |13 7 0 | 29 3 0 0 |
|13 Dec | 221 | 191 | 7,080 |15 2 0 | 19 3 0 0 |
|14 Dec | 204 | 167 | 6,210 |18 2 0 | 22 0 0 0 |
|15 Dec | 198 | 136 | 5,790 |11 1 0 | 20 1 0 0 |
|16 Dec | 191 | 160 | 5,820 |11 0 0 | 24 0 0 0 |
|17 Dec | 200 | 170 | 6,420 |11 2 0 | 18 3 0 0 |
|18 Dec | 208 | 144 | 5,970 | 6 3 0 | 17 4 0 0 |
|19 Dec | 198 | 205 | 6,480 | 5 3 0 | 24 3 1 0 |
|20 Dec | 186 | 186 | 5,370 | 7 2 0 | 18 2 0 0 |
|21 Dec | 192 | 160 | 5,850 | 7 2 0 | 10 1 0 0 |
|22 Dec | 184 | 146 | 6,150 |12 4 0 | 12 1 1 0 |
|23 Dec | 191 | 126 | 6,180 | 7 0 1 | 14 1 1 0 |
|24 Dec | 189 | 138 | 3,540 | 6 3 1 | 12 3 0 0 |
|25 Dec | 190 | 139 | 1,980 |17 0 0 | 25 1 0 0 |
|26 Dec | 192 | 174 | 2,760 | 5 2 1 | 14 2 0 0 |
|27 Dec | 197 | 171 | 2,160 | 5 0 0 | 17 1 0 0 |
|28 Dec | 193 | 181 | 2,730 | 6 0 0 | 8 1 0 0 |
|29 Dec | 200 | 178 | 3,030 | 2 0 0 | 6 1 0 0 |
|30 Dec | 196 | 173 | 2,640 | 5 3 0 | 11 1 0 0 |
|31 Dec | 184 | 213 | 2,490 | 3 0 0 | 11 1 0 0 |
|_______|_____________|___________|____________|____________|_________________|
** End of Report **
------------------------------
Date: Sat, 19 Jan 91 20:31:05 EST
From: Tommy Mac <18084TM%MSU.BITNET@BITNET.CC.CMU.EDU>
Subject: Re: SPACE Digest V13 #029
Boy oh boy! John and Nick really went at it, huh. But neither of them gave a
clear indication of how they feel about the crucial issues involved in most of
their arguments.
John and Nick: Drop all the guff about Manned/unmanned, Govt/private, "indexed
dollars or resources".... Let's refer to resources when we mean energy, materi
als, knowledge and/or labor. Forget the time frame for now.
Do either of you believe that the resources we can return from or use in space
will exceed those used while launching?
Acknowledge-To: <18084TM@MSU>
------------------------------
End of SPACE Digest V13 #068
*******************