Check out the ACE-HF propagation software - the latest is version 2.05. ACE-HF is propagation forecasting and modeling for Amateur Radio as well as for Shortwave radio Listening and general HF operation. This software is even used by the military and other clients around the world. This software is developed and maintained by the same engineers that keep VOACAP up-to-date. As a result, this software is the most accurate user interface integrated with VOACAP. CHECK IT OUT, TODAY. This software is the most accurate modeling software available, and is endorsed by NW7US. Read the details to find out why.
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Map, Above: Conditions in the D region of the ionosphere have a dramatic effect on high frequency (HF) communications and low frequency (LF) navigation systems. The global D Region Absorption Predictions (D-RAP) depicts the D region at high latitudes where it is driven by particles as well as low latitudes, where photons cause the prompt changes.
Note: At times, images may appear broken or missing, when SDO is working on the AIA/HMI instruments.
Planetary A-index (Ap): 16
| Planetary K-index (Kp): 3
Solar Wind: 601 km/s at 6.0 protons/cm3, Bz is -1.0 nT
(Jul 23, 2017 at 0240 UT)
Here is a video introduction to shortwave / HF amateur radio -- what is it that we amateur radio oprators listen to? If you have not yet been introduced to this world, this is a very basic introduction.
If you are using software utilities such as Ace-HF, that require a "smoothed" sunspot number
(Referred to as the SSN), or, the smoothed 10.7-cm Radio Flux Index,
use the following predicted values in this following table:
Predicted SMOOTHED Sunspot Number And Radio Flux Values
With Expected Ranges
At 0805 UTC, on 9 August 2011, a strong magnitude X6.9 X-ray flare -- the strongest yet in this current solar cycle (Cycle 24) -- erupted on the northwestern solar limb. Here is a HD Movie of the event:
Videos of Interest - Space Weather, Solar Dynamics Observatory, STEREO, and more... from the NW7US YouTube Channel. (Click on the small image to launch the video...)
Video: Voyager Finds Magnetic Foam at Solar Systems Edge
Video: Zoom View of Prominence Eruption and X-Ray Flare - M2.5 Magnitude - June 7 2011
Video: X-Ray Flare, Coronal Mass Ejection, Proton Storm - M2.5 Magnitude - June 7 2011 (Close-up of the video, above)
Video: Stunning Close-up View of M3 X-Ray Flare 24 February 2011
Video: June 2011 20-meter (14-Mhz) JT65A Coverage Map of NW7US Radio Signal
The NW7US Current Sunspot and Geophysical Activity Report
The observations, prognastications, and comments by NW7US
NW7US is Tomas David Hood, Propagation and Space Weather Columnist
for CQ Communications
More about Background X-rays
The hard X-ray energy present from the wavelengths of 1 to 8 Angstroms provide the most effective ionizing energy throughout all of the ionospheric layers in our atmosphere. The GEOS satellites measure these wavelengths and the resulting measurements are reported as the "background X-ray level" throughout the day. A daily average is reported, as well.
Just like X-ray flares, the background hard X-ray level is measured in watts per square meter (W/m2), reported using the categories, A, B, C, M, and X. These letters are multipliers; each class has a peak flux ten times greater than the preceding one. Within a class there is a linear scale from 1 to 9.
If one records the daily background X-ray levels for the course of a sunspot cycle, one would discover that the background X-ray levels remained at the A class level during the sunspot cycle minumum. During the rise and fall of a solar cycle, the background X-ray energy levels remained mostly in the B range. During peak solar cycle periods, the background energy reached the C and sometimes even M levels.
Armed with this information, can we discover any clues as to the current status of Sunspot Cycle 24? Below is a graph plotting the background hard X-ray energy reported by the GEOS satellites since the end of Sunspot Cycle 22. Clearly, we see a noticeable rise in Cycle 24 activity. We're seeing the energy mostly in the B level more often, supporting the view that Cycle 24 is alive and moving along toward an eventual sunspot cycle peak in several years.
Overall, the monthly average background 'hard' X-ray level is rising (as seen by the following plot), showing a change from deep solar cycle minimum. We are certainly in the rising phase of Sunspot Cycle 24. While it has been a slow up-tick over the last eighteen months, I expect to see a more rapid rise during mid to late 2011.
Highlights of Solar and Geomagnetic Activity
Covering the period: 10 - 16 July 2017
Solar activity was at very low levels on 12 Jul, low levels on 10, 11, 13, 15 and 16 Jul and moderate (R1-Minor) levels on 14 Jul. Region 2665 (S06, L=111, class/area Ekc/710 on 09 Jul) produced a majority of the flare activity. However, new Region 2667 (N12, L=155, class/area Axx/010 on 14 Jul) produced all of the C-class activity on 13 Jul including a C8 x-ray event with a Type II radio emission (770 km/s). The largest event of the summary period was a long-duration M2/1n flare from Region 2665 observed at 14/0209 UTC. Associated with this event was a Tenflare (130 sfu) and Type IV radio emission. At 14/0125 UTC, LASCO C2 imagery detected an asymmetric halo CME that was analyzed and modelled to reveal an Earth-directed component with a likely arrival at Earth on 16 Jul.
A greater than 10 MeV at greater than or equal to 10 pfu proton event (S1-Minor) began at 14/0900 UTC, reached a maximum flux of 22 pfu at 14/2320 UTC and ended at 15/1115 UTC.
The greater than 2 MeV electron flux at geosynchronous orbit was at moderate flux levels then entire summary period. A maximum flux of 942 pfu was observed at 14/1750 UTC.
Geomagnetic field activity was at quiet to unsettled levels, with isolated active intervals, on 10-11 Jul due to waning effects from a positive polarity CH HSS. Solar wind speeds reached a peak of about 650 km/s early on 11 Jul and steadily decreased through the summary period to reach a low speed of 287 km/s at 16/0446 UTC. Quiet levels were recorded from mid-day 11 Jul through early on 16 Jul.
At 16/0515 UTC, an interplanetary shock associated with the arrival of the 14 Jul CME, was observed in DSCOVR solar wind data. Solar wind speeds sharply increased from around 320 km/s to 502 km/s. Solar wind speeds then slowly increased to a peak value of 643 km/s observed at 16/2037 UTC. Total field strength values reached 28 nT at 16/0836 UTC while the Bz component was sustained at around -23 nT for a prolonged period following the shock arrival. Solar wind density reached a peak of around 56 particles/cubic cm following the shock and the phi angle became highly variable after 16/0515 UTC. Phi angle settled into a mostly positive (away) solar sector after 16/1100 UTC. The geomagnetic field was quiet until 16/0601 UTC when a geomagnetic sudden impulse was observed (40 nT at Hartland magnetometer) indicating the arrival of the 14 Jul CME. The geomagnetic field responded with active to G1 and G2 (Minor to Moderate) geomagnetic storm levels through the remainder of 16 Jul.
Monthly and smoothed sunspot number - The monthly mean sunspot number (blue) and 13-month smoothed monthly sunspot number (red) for the last five cycles. You can see that this current cycle, Cycle 24, is a weak cycle, compared to the last few.
(Click to see actual size)
Daily and monthly sunspot number (last 13 years)
Daily sunspot number (yellow), monthly mean sunspot number (blue), smoothed monthly sunspot number (red) for the last 13 years and 12-month ahead predictions of the monthly smoothed sunspot number:
SC (red dots) : prediction method based on an interpolation of Waldmeier's standard curves; It is only based on the sunspot number series.
CM (red dashes) : method (from K. Denkmayr and P. Cugnon) combining a regression technique applied to the sunspot number series with the aa geomagnetic index used as a precursor (improved predictions during the minimum phase between solar cycles).
(Click to see actual size)
What is 'Space Weather'? Click on these two information slides to view them in full size:
Solar Flares: Quiet conditions (<50% probability of C-class flares) Geo-Disturbance: Quiet (A<20 and K<4) Solar Proton Event: Quiet
Comment from the SIDC (RWC Belgium): With no spotted regions on disk, no Solar flaring activity was recorded and this is expected to remain so. No Earth directed CMEs have been observed in coronagraph data. Solar proton fluxes are at background values and are expected to remain so.
Three Day Forecast of Solar and Geomagnetic Activity
(as of 2200Z on 07 Dec 2014)
Solar activity is expected to be low with a chance for M-class flares on days one, two, and three (08 Dec, 09 Dec, 10 Dec).
The geomagnetic field is expected to be at quiet to minor storm levels on day one (08 Dec), quiet to active levels on day two (09 Dec) and quiet levels on day three (10 Dec).
Forecast of Solar and Geomagnetic Activity
17 July - 12 August 2017
Solar activity is expected to be low with a chance for M-class flare activity (R1-R2 / Minor-Moderate) through 19 Jul when Region 2665 exits the visible disk. Very low to low levels are expected from 20-28 Jul. A chance for R1-R2 activity is possible with the return of old Region 2665 from 29 Jul - 12 Aug.
There is a chance for an S1 (Minor) solar radiation storm through 19 Jul due to potential significant flare activity from Region 2665. No proton events are expected from 20-28 Jul. A chance for S1 (Minor) solar radiation storms is possible with the return of old Region 2665 from 29 Jul - 12 Aug.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to be reach high levels on 19-20 Jul due to influence from the 14 Jul CME. Normal to moderate levels are expected for the remainder of the outlook period.
Geomagnetic field activity is expected to be at G1-G2 (Minor-Moderate) geomagnetic storm levels on 17 Jul due to continued CME effects. Unsettled to active levels are expected on 21-22 Jul and again on 05-06 Aug, with G1 (Minor) geomagnetic storm levels likely on 05 Aug, due to positive polarity CH HSS influence. Quiet to unsettled levels are expected for the remainder of the outlook period.
Be sure to check the Date shown in each photo - is it today's date?
(click to enlarge)
Check out these books on Radio Propagation:
+ The New Shortwave Propagation Handbook (Paperback) - by George Jacobs, Theodore J. Cohen, R. B. Rose. The NEW Shortwave Progagation Handbook may well be the only book you'll need on the subject of ionospheric propagation! It is a "must read" for Radio Amateurs, Shortwave Listeners, and radio communicators of any type who need to make the most productive use of the radio spectrum, regardless of the time of day, the season of the year, or the state of the sunspot cycle. It will become your ever-present companion a the operating table as you master the art of shortwave radio progagation.
+ How Radio Signals Work (Paperback) - by Jim Sinclair. This book provides a basic understanding of the way radio signals work-without becoming bogged down with the technicalities. It covers all kinds of radio signal types--including mobile communications, short-wave, satellite, and microwave. No detailed knowledge of electronics or mathematics is required. A-Z coverage of radio signals including satellites, mobile communications, and short-wave radio. No math or electronics background necessary.
+ Introduction to RF Propagation (Hardcover) - by John S. Seybold. This book provides readers with a solid understanding of the concepts involved in the propagation of electromagnetic waves and of the commonly used modeling techniques. While many books cover RF propagation, most are geared to cellular telephone systems and, therefore, are limited in scope. This title is comprehensive-it treats the growing number of wireless applications that range well beyond the mobile telecommunications industry, including radar and satellite communications.
Data and images courtesy of IPS Australia, NOAA, NASA, SWPC, SIDC
Layout, analysis, commentary, and certain forecasts and content is Copyright, 2017, Tomas David Hood (NW7US), all rights reserved.
No part, except for the space weather 'banners', may be copied without express permission.