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Radio Propagation : Space Weather : Sunspot Cycle Information

a live reference resource site for solar and geomagnetic data and images
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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

PropLab Pro
Best ionospheric ray-tracing software for Radio Operators
PropLab Pro Ray-tracing Software

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

Take a listen to the Space Weather Podcast!

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:

+ Sunspot Cycle/MUF/FOT Tables
+ Current Optimal Frequencies
+ Aurora Resources

How-To Articles:

- Is HF Propagation Reciprocal?
- De-mystifying HF Radio Propagation and Modeling

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.

Main Site Menu:

- Main NW7US Page
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This website is kept alive by Tomas (NW7US), out of "spare change" (which there's not always enough of), and, by the kind, helpful people who visit this website. Would you like to help me keep this site running 24/7? If you are able to help me keep this website up and running, please: help me keep this site running for everyone... click on this donation button:

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Other links of interest:

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Want to learn about Propagation and Space Weather? - Take the STD Space Weather Education Course, today!

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Comments? Please use the feedback form. I look forward to hearing your comments.

Check out some of the other activities that I am involved in:

Web hfradio.org

Subscribe to my Space WX RSS Feed:
(Opera 9.x):

Warnings/Alerts issued
in the last 24 hours, if any:

(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

+ SpaceW.com 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 24 Planetary A Index (Ap) Monthly Progress
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.

(Use http://hfradio.org/propsupport/prop.rss as your RSS channel url)

This page was rendered on 30-Nov-15 1135 UTC.
This page was first created in 1998, by Tomas David Hood (NW7US)

Current Sunspot Cycle 24 Activity and Space Weather

Sun Spots: 47 as of 11/29/2015 :: 10.7-cm Flux: 96 SFU
(SFU=Solar Flux Units)

Space Weather Overview Graphic from SWPC

Watch Five Very Intense X-class X-ray Flares Erupt, Back-to-back!
(From the largest sunspot region in 20+ years...)

Check out the X2.7 X-ray Flare (May 5 2015) - 'Biggest' of 2015, so far

See highlights of the last five years of the Sun, as seen by SDO

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.

Planetary A-index (Ap): 9 | Planetary K-index (Kp): 5
Solar Wind: 541 km/s at 3.0 protons/cm3, Bz is -2.0 nT
(Nov 30, 2015 at 1130 UT)

X-ray Solar Flares:
6h hi [B8.7][0837Z 11/30] 24h hi [B8.7][0837Z 11/30]

Background X-ray Level, Last Six Days

Nov 29 2015 :: B1.6
Nov 28 2015 :: B1.6
Nov 27 2015 :: B2.0
Nov 26 2015 :: B2.8
Nov 25 2015 :: B3.1
Nov 24 2015 :: B3.7

Check out the current Aurora Oval and activity.

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:

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 1100Z on 30 Nov, 2015
High Latitude: Fair-Poor
Middle Latitude: Fair
Low Latitude: Normal

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

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 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: 16 - 22 November 2015

Solar activity was at very low to low levels over the period. Low levels occurred on 17-18 November and 21-22 November with Regions 2454 (N13, L=121, class/area Dac/130 on 22 Nov) and 2457 (N11, L=032, class/area Dsi/130 on 21 Nov) responsible for the C-class flare activity. The largest flares of the period were a pair of C5/Sf flares at 22/0210 UTC and 22/0538 UTC originating from Region 2454 which was in a growth phase after 21 November.

Two filament eruptions were observed at the beginning of the period that resulted in coronal mass ejections (CMEs). The first was an approximate 21 degree long filament, centered near S11W17, that lifted off around 15/2114 UTC. The second was an approximate 19 degree filament, centered near S26W24 that lifted off around 16/0114 UTC. Two CMEs were observed lifting off the SW limb in SOHO/LASCO C2 imagery at 15/2336 UTC and 16/0312 UTC, respectively. Analysis of these CMEs indicated a likely glancing blow early on 19 November. Later in the period, another filament eruption, centered near S20E10, occurred around 22/0600 UTC. An associated CME, observed in C2 imagery beginning at 22/0836 UTC, was mostly directed off the east limb. Subsequent analysis of this CME indicated a very low chance for a glancing blow.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was at high levels on 16 November with a maximum flux of 3,129 pfu at 16/1525 UTC. Normal to moderate levels were observed from 17-22 November.

Geomagnetic field activity ranged from quiet to minor storm periods over the period. Solar wind conditions began the period near nominal levels with prolonged periods of southward Bz near -6 nT on 16 November. Subsequently, the geomagnetic field responded with unsettled to active periods. Quiet to unsettled levels were observed on 17 November. At approximately 17/1941 UTC, a solar sector boundary crossing to a mostly negative (towards) sector occurred followed by an increase in solar wind speed from 370 km/s to around 530 km/s by early on 19 November. An abrupt increase in total field from 6 nT to 12 nT occurred at 18/1925 UTC with a maximum southward deflection of the Bz component to -11 nT indicating the likely arrival of the CMEs from 15-16 November coupled with influences from a negative polarity coronal hole high speed stream (CH HSS). A geomagnetic sudden impulse (70 nT at the Wingst magnetometer) was observed at 18/2010 UTC. The geomagnetic field responded with (G1) minor storming late in the period on 18 November with quiet to active conditions on 19 November. Solar wind speed continued a slow decay over the rest of the period to background levels resulting in quiet to unsettled levels on 20-21 November and quiet conditions on 22 November.

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)
Monthly and smoothed sunspot number chart

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)
Daily and monthly sunspot number (last 13 years)

What is 'Space Weather'? Click on these two information slides to view them in full size:

What is Space Weather? Slide 1 of 2 What is Space Weather? Slide 2 of 2

View of numbered sunspot regions and plages (if any)
Source: http://www.solarmonitor.org/.
(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 2015 Nov 30 1130Z: Bz: -2.1 nT
Bx: -6.1 nT | By: -2.1 nT | Total: 6.8 nT
Most recent satellite polar pass:
Centered on 12/09/2014 : 1725 UTC
Aurora Activity Level was 4 at 1725 UTC
visit noaa for latest.

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

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 07 Dec 2014)

Solar Forecast:

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).

Geomagnetic Forecast:

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
23 November - 19 December 2015

Solar activity is expected to be low with a chance for M-class (R1-R2, Minor-Moderate) flares from 23-25 November due to flare potential from Region 2454. Very low to low levels are expected from 26 November through 07 December. There is also a chance for M-class flare activity from 08-19 December with the return of old Region 2454 (N13, L=121).

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 with high levels likely from 26-28 November and again from 06-13 December due to CH HSS influence.

Geomagnetic field activity is expected to be at unsettled to active levels from 25-26 November and 05-12 December with (G1) minor storming likely on 06-07 December due to recurrent CH HSS activity.

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

foF2 Map from IPS, Australia

Space Weather + Ham Radio Resources

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
showing plasma rain on the Sun!

Check out this amazing NASA SDO (Solar Dynamics Observatory) video
showing a prominence the Sun:

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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

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'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.

NOTE: The certificate is no longer being offered. The course, never-the-less, still provides you with a very well-rounded knowledge base with which you can understand and work with space weather and radio propagation data.

Purchasing the Course

path Please choose one of the following course packages.
  • Purchase: The course alone (no software), delivered over the Internet.

    • Now: $79.99 - normally $250 USD
    • Pay Online by clicking the PayPal button:
      Note: This is only the course - no software. You are paying for the knowledge and content.

  • Purchase: The course with all software, delivered over the Internet.

    • SALE! BUY NOW AT $95.00 - compare to the normal price: $300 USD

    • Includes software: PropLab-pro Version 3.0
    • Pay Online by clicking the PayPal button:
      Note: You are paying for the knowledge and content of this course, PLUS GETTING THE SOFTWARE, TOO!

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


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, 2015, Tomas David Hood (NW7US), all rights reserved.
No part, except for the space weather 'banners', may be copied without express permission.

Last Update: August 20, 2015