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I highly recommend the following...

This is the best propagation modeling and circuit simulation software for Amateur and Shortwave Radio Operators
ACE-HF Modeling Software

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Hot: STD Space Weather Course
This is an excellent self-study course on Space Weather and Radio Propagation. This is a very in-depth and rich course that will equip you with the knowledge you need for understanding Space Weather, the ionosphere, how radio signals propagate via the ionosphere, and much more. Check it out!
STD Space Weather Course

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NW7US Space Weather / Radio Proapgation Podcast; E4 - Subject: No more sunspots by 2015!? It is possible, if the trend revealed in current sunspot research at Kitt Peak, AZ, continues. Listen now!

Podcast home: NW7US Podcast

Gain the on-air edge: This article explains how the ANTENNA is the key! -> Read this introduction to Antenna Modeling



X-ray Conditions (Flares) 5-min.

X-ray plot

X-ray Conditions (Flares) 1-min.

X-ray plot

Geomagnetic Conditions (Kp)

plot of Kp

Satellite Environment Plot:

Satellite Environment Plot

Main Propagation Menu:

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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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Warnings/Alerts issued
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(Key: NOAA Scales)

[ live aurora display ]
[ auroral power maps ]

[ d-layer conditions ]

[ latest solar images 1 ]
[ latest solar images 2 ]
[ latest solar images 3 ]

[ active solar regions ]
[ current solar region image ]

[ What is a flare and its class? ]

Recent Space Environment Reports:

+ Reports of Solar & Geophysical Activity
+ Solar & Geophysical Activity Summaries

From the Space Environment Center:

Solar X-ray Flux

+ A 3 day plot of 5-minute solar X-ray flux values measured on the GOES 8 and 10 satellites.
+ A 6-hour 1-min Solar X-ray Flux plot

Satellite Environment Plot

[ Proton Flux ] [Electron Flux ]
[ GEOS Hp ] [ Estimated Kp ]

Additional Resources

+ Aurora Network
+ D-Layer Absorption Conditions/Predictions
+ 160 Meter Propagation Forecast
+ Solar Physics Department of the Royal Observatory of Belgium, the official keepers of sunspot data.

Solar Activity Forecast
The Forecast of Solar Activity as well as Geomagnetic Activity

Probability of Flares
and Proton Events
0-24 hrs
24-48 hrs
Geomagnetic Activity Probabilities

Middle latitudes
High latitudes

0-24 hrs
24-48 hrs
0-24 hrs
24-48 hrs
Minor Storm
Major-severe Storm

Solar Sunspot Cycle 24 Progress

Solar Cycle 24 Smoothed Sunspot Progress
Solar Cycle 24 10.7-cm Monthly Progress
[ Solar Cycle Details ]

Do you want the latest solar conditions sent to you as an RSS feed? Click: XML RSS propagation feed

You will need a newsreader for RSS/XML.

This RSS is Validated:
This Propagation RSS Feed is a Valid RSS feed.

(Use as your RSS channel url)

This page was rendered on 23-Apr-14 1921 UTC.
This page was first created in 1998, by Tomas David Hood (NW7US)

Current Sunspot Cycle 24 Activity and Space Weather

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Sun Spots: 136 as of 04/22/2014 :: 10.7-cm Flux: 145 SFU
(SFU=Solar Flux Units)

NOAA Scales Activity
Range 1 (minor) to 5 (extreme)
NOAA Scale
Past 24 hrs

Planetary A-index (Ap): 5 | Planetary K-index (Kp): 2
Solar Wind: 413 km/s at 3.0 protons/cm3, Bz is 2.0 nT
(Apr 23, 2014 at 1914 UT)

X-ray Solar Flares:
6h hi [C1.8][1130Z 10/26] 24h hi [C1.8][1130Z 10/26]

Background X-ray Level, Last Six Days

Apr 22 2014 :: B2.8
Apr 21 2014 :: B7.9
Apr 20 2014 :: B8.5
Apr 19 2014 :: B8.1
Apr 18 2014 :: B8.1
Apr 17 2014 :: B8.1

Check out the current Aurora Oval and activity.

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 flux index,
use the following predicted values in this table:

To understand more about the Maximum Usable Frequencies, and related
science, please read the MUF Basics Page.

Global HF Propagation Conditions
Global HF Propagation Conditions for 1900Z on 23 Apr, 2014
High Latitude: Normal
Middle Latitude: Normal
Low Latitude: Normal

Geomagnetic Latitude Ranges:
High: 60-90 degrees
Middle: 20-60 degrees
Low: 0-20 degrees

At about 2030 UTC on August 31, 2012, a beautiful, huge solar filament broke away from the Sun. Watch this movie:

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: 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: 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
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: 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
Video: June 2011 20-meter (14-Mhz) JT65A Coverage Map of NW7US Radio Signal

The Solar Dynamics Observatory (SDO) Latest Solar Images
Click on an image for full-sized view

SDO - Solar Dynamics Observatory     SDO - Solar Dynamics Observatory

D Region Absorption Predictions (D-RAP) Global Map

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.

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.

Background X-ray (1 to 8 Angstrom) Plot

Highlights of Solar and Geomagnetic Activity
Covering the period: 14 - 20 April 2014

Solar activity began the period at low levels but reached moderate levels toward the end of the period due to a pair of M-class x-ray flares. The first M-class event was an M1/1n flare (NOAA Scale R1-minor radio blackout) at 16/1959 UTC from Region 2035 (S15, L=223, class/area=Ekc/340 on 18 Apr) that had an associated Type-II radio sweep (estimated speed 1,071 km/s). A subsequent coronal mass ejection (CME) was observed in SOHO/LASCO coronagraph imagery beginning at 17/0125 UTC that had a partial Earth-directed component with a line-of-sight speed estimated at 642 km/s, although the bulk of the ejecta being directed south of the ecliptic plane.

The second M-class event of the period was an M7 flare (NOAA Scale R2-moderate radio blackout) at 18/1303 UTC from Region 2036 (S15, L=246, class/area=Dhc/510 on 17 Apr) that had an associated Tenflare (1,000 sfu), a complex Castelli-U radio burst signature, a Type-II radio sweep (estimated speed 851 km/s), and a Type-IV radio sweep. A subsequent Earth-directed, asymmetric-halo CME was observed in SOHO/LASCO coronagraph imagery beginning at 18/1325 UTC with a line-of-sight speed estimated at 1,000 km/s.

A pair of very faint CMEs were observed late on 15 Apr and early on 16 Apr but the source regions for these CMEs were difficult to determine.

Regions 2035 and 2036 were the most productive regions on the disk this period and were amongst the most magnetically complex regions on the disk, joining Regions 2034 (N04, L=244, class/area=Ekc/480 on 18 Apr) and 2037 (S09, L=245, class/area=Dai/110 on 17 Apr) as regions with beta-gamma magnetic configurations.

Late in the period Region 2032 (N12, L=274, class/area=Cso/160 on 15 Apr) produced three low-level C-class flares as it transited the west limb with numerous subsequent non-Earth-directed CMEs that were narrow and directed away from Earth.

An energetic particle enhancement was observed following the M7 flare detailed above. The greater than 10 MeV proton flux exceeded 10 pfu (NOAA Scale S1-minor solar radiation storm) at 18/1525 UTC and reached a maximum value of 58 pfu at 19/0105 UTC before beginning to decline. The decline was interrupted with the passage of an interplanetary (IP) shock that was observed at the ACE spacecraft at 20/1057 UTC where 10 MeV proton flux values briefly increased from 15 pfu to 30 pfu before rapidly plummeting below the S1 threshold at 20/1155 UTC. The greater than 100 MeV proton flux also become enhanced during the M7 flare, reaching a maximum value of 0.6 pfu, but ultimately remained below alert levels.

The greater than 2 MeV electron flux at geosynchronous orbit was at normal to moderate levels throughout the period.

Geomagnetic field activity began the period at predominately quiet levels with isolated periods of unsettled conditions due to a mostly nominal solar wind environment. Active conditions were observed early on 19 Apr (0000-0600 UTC) followed by predominately unsettled conditions due to the likely arrival of one or both of the faint CMEs from 15/16 Apr. A weak IP shock was observed at the ACE spacecraft at 19/1754 UTC, presumably due to the arrival of the 16 Apr CME, causing quiet to unsettled conditions late on 19 Apr and into the early hours of 20 Apr. Another shock was observed at ACE at 20/1057 UTC, likely associated with passage of the 18 Apr CME, which caused minor geomagnetic storming (NOAA Scale G1-minor) from 1200-1500 UTC followed by three periods of active conditions (1800-2359 UTC) to end the period.

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View of numbered sunspot regions and plages (if any)
(Click for large view)

Active Regions and Plages

Active sunspot regions, and plages, identified by SIDC

SIDC Solar Disc with active regions and plages

Latest GOES 15 Image of the Sun

Latest GOES-15 Image of the Sun

STEREO Behind Image
What is coming
SOHO EIT 195 Image
Current View
STEREO Ahead Image
What was...

Real Time Solor Wind and Aurora:

On 2014 Apr 23 1808Z: Bz: -1.9 nT
Bx: 4.5 nT | By: -4.1 nT | Total: 6.4 nT
Most recent satellite polar pass:
Centered on 04/23/2014 : 1742 UTC
Aurora Activity Level was 6 at 1742 UTC
visit noaa for latest.

[ See this current Aurora Oval Map ]

This is a video of the simulation from May 27-28, 2011, showing
the Geomagnetic disturbance caused by the solar wind

All NICT images are Copyright@NICT,
used by express, written permission from NICT

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Space Weather and Propagation Forecast
Prepared by the US Dept. of Commerce, NOAA,
and the Space Weather Prediction Center

Three Day Forecast of Solar and Geomagnetic Activity
(as of 2200Z on 21 Apr 2014)

Solar Forecast:

Solar activity is expected to be low with a chance for M-class flares and a slight chance for an X-class flare on day one (22 Apr) and expected to be low with a chance for M-class flares on days two and three (23 Apr, 24 Apr).

Geomagnetic Forecast:

The geomagnetic field is expected to be at quiet to active levels on day one (22 Apr) and quiet to unsettled levels on days two and three (23 Apr, 24 Apr). Protons greater than 10 Mev have a slight chance of crossing threshold on day one (22 Apr).

Forecast of Solar and Geomagnetic Activity
21 April - 17 May 2014

Solar activity is expected to be at low levels with a chance for moderate (R1-R2 (Minor-Moderate)) events throughout the period.

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at normal to moderate levels throughout the period.

Geomagnetic field activity is expected to be at active to G1 (Minor) levels on 21 Apr due to coronal mass ejection (CME) effects, decreasing to unsettled to active conditons on 22 Apr as CME effects diminish. Quiet to unsettled levels are expected on 23-25 Apr due to a weak negative polarity coronal hole high speed stream (CH HSS). Predominately quiet conditions are expected for 26 Apr-13 May barring any influence from transient features. Isolated unsettled conditions are possible on 14-15 May due to an unclassified recurrent solar wind feature with quiet conditions returning for 16-17 May to end the period.

Real-time foF2 map from IPS (Ionospheric Prediction Service), Australian Space Weather Agency

foF2 Map from IPS, Australia

Space Weather Page

Click on image to
view larger versions

The following images
are from SOHO

C2 LASCO Image
C3 LASCO Image

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Check out this amazing NASA SDO (Solar Dynamics Observatory) video
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Additional Views of the Sun

Be sure to check the Date shown in each photo - is it today's date?
(click to enlarge)

Current Numbered Sunspots / MDI MagnetogramCatania Solar Disc

H-Alpha View 1H-Alpha View 2

Space Weather Information Monitor Software - sample screen shot Interested in keeping tabs on ALL of the current Space Weather information? Check out the Space Weather Information Monitor Software (SWIM) - support the NW7US / Propagation Resource Center and purchase your copy of SWIM, today.

With SWIM, you can monitor, display, animate or print to your printer over 200 default space-weather related Internet resources, in real-time. You can use SWIM to expand and manage THOUSANDS of additional internet resources quickly and easily. Simply cut and paste Internet URLs of resources you find interesting and SWIM will immediately begin managing those resources for you. Retrieve the latest space weather forecasts and summary reports. Add any number of other textual reports you find on the Internet.

Find out the full details about the Space Weather Information Monitor Software (SWIM).

Purchase the STD Internet Space Weather & Radio Propagation Forecasting Course

Solar Terrestrial Dispatch (STD) is a world-leader in space weather forecasting services, as was demonstrated in late October and early November 2003 (Oler, C., "Prediction Performance of Space Weather Forecast Centers during the Extreme Space Weather Events of October and November 2003," published in the peer-reviewed scientific journal "Space Weather" by the American Geophysical Union in 2004). A copy of this paper is available here.

STD expertise is used to provide high-quality space weather forecast services to many electrical power companies across North America, guidance to spacecraft operators and consultation to many others.

STD has developed a special space weather course designed to teach individuals without any background how to predict space weather (see below). The STD Space Weather Course was the recipient of the Study-Web Academic Excellence award.

The course is available on-line as a small group of downloadable Adobe Acrobat Reader documents comprising over 630 pages of printed material (for sample pages, click here). You can therefore choose to study the material on your computer or print it out for study.

The course, if you choose the option, also includes the STD workhorse, Space Weather Information Monitor (SWIM) software, which is the most comprehensive space and weather information monitor in the world. The course (if you choose the option, below) also includes the STD's powerful and popular Proplab-Pro HF Radio Propagation Laboratory software! All software products are optional elaborate tools that will contribute to your application of the knowledge obtained through this course.

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NOTE: After you finish ordering, through PayPal, please allow me time to process your order. I am not always in front of my computer, so it may take a while for me to finish the processing of your order. I shall e-mail you the moment I have processed the order, and will give you specific directions on how to download the Course file(s). PLEASE BE PATIENT WITH ME!

A list of the topics covered in this home-study course include:
  • The Sun
    • Basics of the Sun
    • Sunspots
      • Types of Sunspots
      • Sunspot Magnetic Fields
    • Solar Radiation and Radio Emissions
    • Solar Cycles
    • Techniques for Modelling Solar Cycles
    • Sources of Information and Imagery
  • Interplanetary Space
    • The Solar Wind
    • Magnetic Fields
    • Heliospheric Current Sheet
    • Solar Sector Structures
  • The Earth
    • Magnetosphere
      • The quiet magnetosphere
      • The disturbed magnetosphere
      • Understanding Magnetic Indices
      • Magnetic Storms
        • Sudden Storm Commencements (SSCs)
        • Gradual Storm Commencements
      • Geomagnetically Induced Currents (GICs)
        • Effects on Electrical Hydro Systems
        • Effects on Other Long Conductors
    • Ionosphere
      • Formation of Ionospheric Layers
      • Factors Affecting Ionospheric Layers
  • Solar Disturbances
    • Transient Solar Coronal Mass Ejections (CMEs)
      • Types and Structures of Coronal Mass Ejections
      • Understanding the Importance of CME Structures
      • Inferring CME Structures from Available Solar Data
      • Coronal Mass Ejection Detection Methods
      • Using IMPACT (software) to Aid in CME Disturbance Predictions
      • Solar Cycle Dependencies
    • Solar Flares
      • Basic Nature of Flares
      • Types of Flares
      • Flare Rating Systems
      • Significance of Proton Flares
      • Ground Level Events (GLEs)
      • Fast Transit Events
      • Interpreting Magnetograms
      • Determining Magnetic Shear and Flare Susceptability
      • Solar Flare (and Proton Flare) Prediction Techniques
      • Solar Flare Related Coronal Mass Ejection Prediction Techniques
      • Sources of Solar Flare Information
    • Solar Coronal Holes
      • Coronal Hole Basics
      • Recurrence
      • Solar Cycle Correlations
      • Associations with Near-Relativistic Electrons
      • Coronal Hole Related Disturbance Prediction Techniques
    • Filament Eruptions
      • Filaments and Prominences
      • Eruptive and Non-Eruptive Activity
      • Filament-Associated Coronal Mass Ejections
      • Filament-Related Disturbance Prediction Techniques
  • Auroral Activity
    • Basic Theory of the Northern/Southern Lights
    • Behavioral Characteristics of the Auroral Ovals
    • Sensitivity to Solar Disturbances
    • Affects on Satellite Health and Radio Communications
    • Mathematical Models of the Auroral Zones
    • Auroral Activity Prediction Techniques
    • Information Sources
  • Conditions Affecting Satellite Health
    • Atmospheric Drag
    • Surface Charging Anomalies
    • Deep Dialectric Charging Anomalies
    • Interplanetary Shocks
    • Magnetopause Crossings
  • Postulated Sun/Earth Climate Connections
    • Possible Long-Term Climatic Trends
      • Rainfall
      • Temperatures
      • Atmospheric Pressure
      • Storm Tracks
      • Ozone Correlations
    • Possible Short-Term Meteorological Trends
      • Pressure and Winds
      • Lightning
      • Storm Systems
      • Ozone Responses
  • Radio Propagation
    • Basic Theory (Non-Technical)
      • Characteristics and Components of Radio Signals
      • Understanding Plasmas
      • Importance of Electron Collisions
      • Appleton/Hartree Contributions
      • Signal Polarization and Coupling
      • Ionospheric Absorption
        • Deviative Absorption
        • Non-Deviative Absorption
      • Fading
      • Multipathing
      • Travelling Ionospheric Disturbances
      • Solar Related Disturbances
      • Structure of the Ionosphere
        • Ionospheric Layers
        • Importance of Sporadic-E
        • Effects of Spread-F
        • Solar-Cycle Dependencies
        • Models of the Ionosphere
          • Simple Mathematical Models
          • Numerical Maps
          • CCIR
          • URSI
          • The International Reference Ionosphere (IRI)
          • Others
        • Probing the Ionosphere
        • Probing Techniques
        • Probing Instruments
        • Sources of Ionosonde Information
    • Basic Ray-Tracing Concepts
      • Ordinary vs Extraordinary Signals
      • Becoming Familiar with Ray-Tracing Software
    • Ray-Tracing in Three-Dimensions
      • Ray-Tracing Software Considerations
      • Preparing for 3D Ray-Tracings
      • Performing 3D Ray-Tracings
      • Studying 3D Ray-Tracing Results
    • Vertical Radio Signal Propagation
      • Signal Reflection Behavior
      • Critical Frequencies
      • Ray-Tracing Vertically-Incident Signals
    • Oblique Radio Signal Propagation
      • Signal Refraction/Reflection Characteristics
      • Effects of Geomagnetic Activity
      • Effects of Solar Activity
      • Ray-Tracing Obliquely Incident Radio Signals
      • Determination of Maximum Usable Frequencies
        • Simple Empirical Methods
        • Ray-Tracing Techniques
      • Effects of Sporadic-E
      • Non-Great-Circle (NGC) Propagation
        • Responsible Conditions
        • Compensation Methods
        • Ray-Tracing Techniques to Analyze NGC Propagation
      • Chordal-Hop and Inter-Layer Ducting Propagation
        • Advantages and Disadvantages
        • Analysis using Ray-Tracing Techniques
      • Searching for and Exploiting Exotic Propagation Paths
        • Properties of Exotic Paths
        • Searching for Exotic Paths using 3D Ray-Tracing Techniques
        • Determining the Most Reliable Exotic Radio Paths
    • Ionospheric Disturbances
      • Solar Related Disturbances
        • Solar Flares and Related Coronal Mass Ejections
        • Coronal Holes and High Speed Solar Wind Streams
        • Filament Related Coronal Mass Ejections
        • Impact of Flare Related Radio Noise Bursts
      • Short Wave Fadeouts
      • Sudden Phase Anomalies
      • Sudden Frequency Deviations
      • Devastating Effects of Polar Cap Absorption
      • Disturbances and their Effects on Satellite Communications
  • Radio Propagation Prediction Methods
    • Short-Term Forecasting Techniques
    • Medium-Term Forecasting Techniques
    • Long-Term Forecasting Techniques
    • Sources of Forecasting Information
  • Applied Forecasting Techniques
    • Climatology
    • Pattern Recognition
    • Compiling Necessary Information
    • Exploiting Databases
    • Computer Related Aids
    • Studying Real-Life Examples
    • Developing Experience and "Intuition"
  • Field Experience
    • The STD SW Course presents you with some specific historic real-life scenarios. Using the information and techniques studied in this course, you are asked to develop your own space-weather and radio-propagation predictions. The actual real-life impacts are then studied and compared with your forecasts.
    • The Course presents you with several hypothetical (possible future) examples and ask you to develop your own forecasts.
  • Course Completed

Although this course is largely self-taught, STD will provide support if you run into difficulties. There are no prerequisites.

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.

I write the propagation columns for the following magazines:

CQ Magazine CQ Magazine America's fastest growing magazine for the active ham radio operator. CQ is the world's leading independent magazine devoted to amateur radio. For more than a half-century, CQ has been on ham radio's leading edge -- the first to promote mobile operating (in the 1950s), semiconductors (in the 1960s) and packet radio -- the original e-mail (in the 1980s). The amateur satellite program got its start with an idea in the pages of CQ!

CQ VHF Magazine CQ VHF Magazine It is back! May 2002 saw the return of this quarterly magazines that focuses on amateur radio above 50 MHz. Articles and columns target both the beginner as well as the expert.

Popular Communications Magazine Popular Communications Magazine Exciting reading for the shortwave and scanner listener. It features authoritative information on scanner monitoring of police, fire, utility and aircraft transmissions as well as short wave listening, monitoring short wave digital, fax and teletype broadcasts, cb radio, alternative radio, clandestine radio, telephones and wiretapping, bugging, surveillance, pirate broadcasters, military communications, amateur radio, satellite tv reception, radio history and nostalgia.

Monitoring Times Magazine Monitoring Times Magazine Contains news, information, and tips on getting more out of radio listening. Do you own a radio, a shortwave receiver, a scanning receiver, or a ham radio? Then Monitoring Times® is your magazine! Open a copy of MT, and you will find 92 pages of news, information, and tips on getting more out of your radio listening. In fact, it's the most comprehensive radio hobby magazine in the U.S. Packed with up-to-date information concisely written by the top writers in the field, Monitoring Times® is your foremost guide to profiles of broadcasting and communications installations; home projects; and tips on monitoring everything from air, sea, and space to distant ports of call.

Data and images courtesy of IPS Australia, NOAA, NASA, SWPC, SIDC

Layout, analysis, commentary, and certain forecasts and content is
Copyright, 2013, Tomas David Hood (NW7US), all rights reserved.
No part, except for the space weather 'banners', may be copied without express permission.

Last Update: October 13, 2013