SOLAR PHYSICS WITH 20 MHZ ANTENNAS

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SOLAR PHYSICS WITH 20 MHZ ANTENNAS Powered By Docstoc
					    NRAO
June 27-30, 2004
  Plasma
  Bubble
 Detection
     &
 Analysis
    at
   20 MHz


Professor John C. Mannone            Professor Wanda Diaz
Central Piedmont Community College   University of Puerto Rico
Duke-Cogema-Stone & Webster          Department of Physics
     Spectral Analysis Techniques Developed

SARA Conference July 2003
     Solar Physics with 20 MHz Antennas
     Focus on Solar Flares
     Understanding Solar Radio Propagation Encounters
     Frequency Analysis Computer Simulation

Website Creation Sept 2003
NASA/Radio Jove Bulletin Article October 2003
ORION Lecture October 2003
       Solar-Ionosphere Connection
       Simultaneous Comparative Solar Burst Analysis
       Development of Radio Scintillation Experiments

SARA Conference June 2004
     Plasma Bubble Detection & Analysis
"DETECTION AND ANALYSIS OF PLASMA
BUBBLES AT 20 MHz RADIO FREQUENCY"

ABSTRACT
Charge deficient holes in the F-region, called plasma bubbles, are
typically detected above the equatorial zone. Some of the traditional
techniques of detection involve sensitive receivers called riometers tuned
to 30 MHz to record time variations or rocket-borne Langmuir probes
measure the fluctuation of electron number density. In this work, the
electron number density variations are recorded indirectly. Astrophysical
radio waves are modulated by these variations as they travel through the
ionosphere. Spectral analysis of decametric radio signals acquired with
20 MHz antennas will provide similar information about the ionosphere.
The behavior of the radio noise floor will show if radio light is
scintillated. This technique is applied to data from Puerto Rico. Though
just north of the magnetic equatorial zone, power spectra disclose radio
twinkling by the sudden post-sunset onset of plasma bubbles just before
local midnight.
Irregularities and Radio Scintillation




Optical Twinkle- Variation refractive index caused by fluctuations
in mass density in the turbulent atmosphere (troposphere)

Radio Twinkle- caused by random fluctuations in electron number
density in the ionosphere

Important in
       Navigation
       Communication
       Pulsar Research
Science & Industry Radio Scintillation Detection


30 MHz Riometer- very sensitive low noise receiver and 4-element
Yagi arrays

Radar Backscatter

Satellite Transmission- FLEETSAT (254 MHz), GPS Satellites
(~1.2 - 1.6 MHz)

Rockets Instrumented with Langmuir Probes- ne fluctuations

Global UV Imager maps ionospheric ions fluctuations (volume
emission rate in the far UV at 135.6 nm, due to the radiative
recombination of the F-layer predominant ion O+, is proportional
to ne2)
Our Methodology on Radio Scintillation Detection

The extent of amplitude modulation of 20 MHz galactic radio
background noise by the medium in its path (not necessarily
restricted to the ionosphere) is determined and compared with
known characteristics.

The signal is too noisy to see the scintillations directly with the
simple inexpensive receiver and phased array dipoles used;
however, spectral analysis reveals the behavior of the noise floor.

In concert with additional information, such as the time and
location of the disturbance, geomagnetic activity, space weather,
etc., the spectral analysis is a good tool that will help determine or
corroborate the state of the ionosphere.

               The Ionosphere is a Plasma
Hot Plasma
Electric and Magnetic Fields Govern the Solar Plasma
Radio Emission Mechanisms



Continuous
             Thermal (Coulomb Scattering)
             Non-thermal (Synchrotron Radiation)

      Discrete
             Atom Transitions (High Rydberg States)
             Hyperfine Transition ( 21 cm spin-flip)
             Molecular Transitions (methanol lines; water masers)
                     p = -0.65




   Radio Spectra
of Various Sources
          20
 Frequency, MHz
             Anatomy of the Ionosphere

Layout, Composition, Formation
Dynamics of Fields and Sources (g, E, B, v, P, m, n, j)
Connectivity/Nonlinear Dynamics
Boundary Flows/Shocks
Space Weather/Terrestrial Weather (El Nina South Atlantic
Oscillation, Hurricanes)
Diurnal, Seasonal, Solar Cycle Effects
Exosphere (space weather)
 40,000 miles / 64,400km
(contains Plasmasphere & Magnetosphere)

Mesosphere
        50 miles / 80km
Thermosphere
        400 miles /640km
(Ionosphere straddle these two spheres)

Stratosphere
         ~30 miles / 50km
Troposphere (neutral atmosphere/weather)
         5 miles / 8.1km at poles
         10 miles / 16.1km at equator
 Solar Wind Deforms Earths Dipolar Magnetic Field


A constant stream of particles flowing 106 mph from the Sun’s
corona extends beyond Pluto’s orbit.
        (106 cm3 = 1 m3 )


                             Note: green line is for Martian ionosphere
                             Chapman profile 120 km, max ne = 5x104 cm-3
Ionospheric Plasma

Formed from complex collision dynamics and photo-ionization
of air molecules involving cosmic rays and UV light.
                    Transparency of Earth’s Atmosphere




    O2 and N2 absorb all l < 290 nm       H2O and CO2 block 10m to 1 cm




Universe, 5th ed. Kaufmann and Friedman
Electron Plasma Frequency- Radio Wave Passage

Or the Langmuir Frequency of Plasma Oscillation

              wpe = (4pe2n0/me)1/2

~15 MHz
on the day side of the earth near sunspot maximum and

~10 MHz
on the night side near sunspot minimum

Layer opaque to all lower frequencies
        Significant Ionospheric Scintillation
                  of Radio Waves

              Caused by Plasma Instabilities

Polar/Auroral Zone
Particle Precipitation

Equatorial Zone
Plasma Plumes and Bubbles

Mid Latitudes
Storm Enhanced Density (SED) from high latitudes
Sudden Storm Enhancement (SSE) from low latitudes
             Plasma Plumes and Bubbles

Equatorial ionosphere illustration
Coupled Ionosphere-thermosphere forecast model

Linked to theoretical growth-rate model (left)
Linked to non-linear plasma bubble evolution (right)
Rayleigh-Taylor Instability
           &
       E x B Drift
RADIO JOVE SYSTEM
Improved version over Radio Jove RJ1.1 receiver, the RF-2001A is
used here (also designed by RF Associates, Dick Flagg)

Local oscillator generates a waveform at frequency around 20.1
MHz. The range of frequencies to tune at 19.950-20.250. The
JFET transistor amplify incoming signals by a factor of 10. The
receiver input circuitry is designed for a 50 Ohm antenna.

The double dipole antenna ( Radio JOVE) is 10 feet above the
ground, aligned east-west, in-phase so the beam is directly
overhead. The maximum gain for a horizontal dipole is 7.3 dBi.
Beam width is 115 degrees. The VSWR is below 1.5:1

Receiver noise figure < 5dB ( 620K). At the operating frequency
of 20.1 MHz the galactic background temperature on the order of
50,000 degrees (this is consistent with the plasma temperature vs.
ne chart).
    Can Equatorial Plasma Bubbles be Detected?

Phenomena normally in the equatorial zone
+/- 20 degrees from the magnetic equator

Most southern participating site is Puerto Rico with
Geographic latitude 18.3N, but Geomagnetic latitude 28.2 N

Data was collected hourly for a period before sunset to after
sunrise (6 AM to 6 PM Atlantic Standard Time). Arbitrarily, the
antenna signal was sampled for the first 10 minutes of each
hour. The sampling rate was 1 Hz.

Though the bubbles only survive around 30 minutes, the
antenna is seeing numerous irregularities. (Future experiments
will acquire more data over a shorter time interval and at a
higher sampling rate).
Greatly exaggerated for clarity
                                                   Plasma irregularity



                      Radio wave path
                                                    Simple trigonometry =>

                                                    sin(q-b)/sin(p-q) = R/(R + z)

                           3 dB       z
                                                             q is angle between the
                           q                                 vertical and the half power
      Antenna site                                           antenna beam width
                                  Latitude of zenith point
                                                             b is the maximum latitude
                       R
                           b                                 displacement
                                                             To see an irregularity at
                                                             height z (typically 600 km)

                                                             R is the radius of Earth:
                                                             6378 km
Questionably in the Zone:
need 8 degrees (28-8 = 20), may only have 3 degrees latitude

E-W phased dipole array with a 60 degree full beam width
and disturbance at 600 or 1100 km, allows no more than 2.8 or 4.8
degrees latitude difference, respectively. (E-W anti-phase
arrangement is preferred allowing 13-19.5 degree reprieve)

This configuration falls short. However, a free dipole array was
assumed.

With the antenna 10 ft (3 m) above the ground (1/5-wavelength),
the antenna pattern may become distorted. Though less sensitive,
it may now see into the equatorial zone similarly to the anti-phase
capability.                               Dipole pattern
                                 free space vs. close to the ground
       Preliminary Data Reduction Sequence


-Radio Skypipe Pro software SPD files converted to TXT files

-Save data in Word document which automatically delimits the
data into 3 columns: date, time, signal strength

-Correct logging errors
(37:.94 must be changed to 37:0.94;
often jumps at the minute intervals; other errors in format or
placement)

-Copy data into Excel and format illegible data


                                   Data Collection & Preparation
-Note that Excel truncates the Hour in Column B. Therefore, label
column as time, min:sec after the hour (e.g., after 22Z). However,
computations in Excel will treat this a fractional day.

-Compute sampling interval time (in seconds) in cell D4 type
 (=(B4-B3)*24*3600)

-Plot Signal Strength vs. Time to reproduce the time series.

-Compute sampling statistics

-Load FFT capability in Excel by executing the submenu path
       Tools/Add-Ins/check Analysis Toolpak/OK

-Excel algorithms require exactly 2N data points for FFT, Use 512.
1024, etc not to exceed 4096.. Truncate or pad as necessary.


                                                   Sampling Statistics
-Perform FFT (Tools/Data Analysis/Fourier Analysis/OK):
        Input the range of data for the signal strength   matching 2N
        points; e.g., C4:C515; direct output, e.g., F4:F515

-Decimate the frequency according to N. That is, step-wise increase the
frequency (sampling frequency/N).

-Calculate spectral power: square the magnitude of the complex number
returned by the FFT (=IMABS(F4)2); propagate to N/2 -1 points to
avoid reflection of results.

-Plot Power Spectrum: Power vs. Frequency.

-Scale the plot down by a factor of around 104 to105 to see the spectral
components above the noise.

-Plot Log Power vs. Log Frequency with close attention to the 100 to
1000 millihertz range for behavior of the noise floor.
                                                     Spectral Analysis
Left Portion of Excel Spreadsheet Analysis



                    Spreadsheet Calculations
The frequency is stepped in about 2 mHz increments
(step = sampling frequency/N = 990 mHz/512 samples)



      Right Portion of Excel Spreadsheet Analysis


                                            Spreadsheet Calculations
        20 MHz Radio Background Noise
University of Puerto Rico, June 6, 2004 11 PM local time




                                        Apparently uneventful
                                      radio noise, just a dc off-set




  Signal Strength vs. Time Graph Reconstruction in Excel
  10 minute time series sampled at 1 Hz (990 +/- 7 mHz)
Typical Power Spectral Density (Power vs. Frequency)
         not very revealing except for ringing
Diffraction and Scattering Models p1

Scintillation caused by change in refractive index, n,
caused by diffraction on irregularities related to electron
number density fluctuations or atmospheric turbulence.
(Appleton-Hartree equation)

Irregularity size >> wavelength, wave front is disturbed,
get random phase modulation; further modulation occurs
before it reaches the antenna => complicated diffraction
pattern.

Temporal variation if source is moving relative to the
receiver.
Diffraction and Scattering Models p2

Phase screen, simplest model: irregular layer replace by
equivalent thin screen a distance z to the antenna (multiple
screen are necessary for extended medium and an
inhomogeneous background).

Fresnel Diffraction leads to power law frequency
dependence f-p where p is the spectral index.

Various types of scintillation lead to different spectral
indices: the quiet sky 0.65, typical ionospheric scintillation
8/3 (2.5), plasma bubbles range 2-8 with average 4,
tropospheric scintillation 11/3, interstellar scintillation like
ionospheric without the seasonal or geographic
restrictions.
Spectral Analysis

Fresnel Zone Speed of rising plasma bubble is estimated
from the corner frequency fc: (V = (lz)1/2 fc)

Spectral Index, p obtained from log Power vs. log
frequency plot after the roll-off (around 50 millihertz) to
about 1 Hz or perhaps 2 or 3 for very strong scintillation
(cut-off frequency for Fresnel filtering). Therefore,
spectral behavior is examined from about 100-1000
millihertz.

S4, Scintillation Index (normalized time averaged signal
strength) (not a good index for our experiment since our
receiver is not sensitive like a riometer).
        Spectral index p = 4 for plasma bubbles
                  over Varanasi, India




Ionospheric Plasma by VHF Waves, R.P. Patel, et al
Pramana Journal of Physics, India Academy of Sciences, Vol 55, No. 5 & 6,
Nov/Dec 2000, pp. 699-705
Spectral index p = 5 for plasma bubbles
      over San Juan, Puerto Rico
Before and After the Irregularity
  log power vs. log frequency
                   Time Variation of Spectral Index



June 6, 2004 6 PM

June 7, 2004 8 PM
             9 PM

           11 PM




           6 AM



                                    June 6, 2004 sunset 6:57 PM 23Z = -01Z 6/7/04
                                    June 7, 2004 sunrise 5:48 AM =    +10Z 6/7/04
Significant change in
slope suggests
multiple phenomena
                                  50 100         1000 mHz




    Corner frequency 316 mHz relates to the first Fresnel zone
    Size and speed of irregularity can be estimated from this
A major change is indicated in the condition of the ionized layer
during the measurement interval.

Each linear segment is analyzed between 100 and 1000 mHz,
the correct range for scintillation observations (the “trend line”
feature in Excel is used to obtain an unbiased linear regression)
Diurnal Variation of Plasma Bubble Growth




                            Radio sky background
                            spectral index -0.65




 Post-sunset (-01Z) and Pre-midnight (+04Z) Growth
             of Suspected Plasma Bubble
View of Eastern Sky/Milky Way from Puerto Rico June 6, 2004 11 PM
Geomagnetic Activity May Enhance the
    Occurrence of Irregularities
     in the Mid-latitude Region
Geomagnetic coordinate treated in this page is "geomagnetic dipole
coordinate" referring to the geocentric dipole field approximating the
geomagnetic field based on International Geomagnetic Reference Field
(IGRF). The poles are the intersections of the dipole axis with the Earth's
surface at (79.5N, 71.6W) and (79.5S, 108.4E)(IGRF 2000), and move
slowly according to "secular variation of the geomagnetic field".

Geomagnetic latitude and longitude are defined as shown in the illustration.
                    HAARP Flux Magnetometer

               "H" component positive magnetic northward
               "D" component positive eastward
               "Z" component positive downward




Geomagnetic storminess is usually indicated in oscillatory variations in the
earth's magnetic field. Additional detail concerning the nature and severity of
the ionospheric disturbance can be found through analysis of the three
components of the field.
   The Geomagnetic Disturbance Storm Index
                  Dst (nT)


During a typical geomagnetic storm the magnetic field is
depressed (H component is negative) everywhere in the
middle and lower latitudes of the Earth.
 From Some of my Radio Astronomy Web Resources
        “Adventures in Astronomy by John C. Mannone”

Society for Amateur Radio Astronomers (SARA)
NASA Project Radio Jove
Space Physics & Aeronomy on the Web
Solar X-ray & Geomagnetic Storm Monitor
Sun-Earth Connection Data Availability Catalog Mission Overview
Matrix
WIND Daily Spectrogram Plots and Type II & IV Solar Burst Lists
SOHO Data
The Sun Now
SOHO Instruments
Solar & Heliospheric Weather Model (IMSAL)
Solar Physics on the Web
Latest Solar Events
Yohkoh GOES Data Base Browser
Australian Space Weather Agency
Aside
Storm Enhanced Density

SED is the ionospheric signature of the erosion of the outer
plasmasphere by ring current-induced disturbance electric
fields. The low-altitude ionosphere: appearance of sunward-
convecting regions of enhanced plasma density at mid latitudes.

Millstone Hill incoherent scatter radar has observed SEDs in
the pre-midnight sub-auroral ionosphere during the early stages
of magnetic storms.

These high-TEC plumes of ionization appear at the
equatorward edge of the mid-latitude ionospheric trough and
stream sunward driven by poleward-directed electric fields at
the equatorward limit of region of sunward convection.
SED

High TEC observed northern Florida ( July 15, 2000 Kp=9
event) and the north-central USA is more typical of pre-
midnight SED events for Kp=5 or 6.


                                 Snapshot of SED plume in
                                 the post-noon sector obtained
                                 vertical TEC from > 120
                                 GPS receiving sites during a
                                 15-min interval. Red contour
                                 denotes the instantaneous
                                 position of the SED/TEC
                                 enhancement.
                        CONCLUSIONS

-spectral analysis of radio signals provides a potential probe of the
intervening media the wave propagates through

-inexpensive and extensive equipment and readily available
resources renders this favorable to amateur radio astronomy

-state of ionosphere can be examined by monitoring the radio
noise floor as a function of time in concert with space weather and
geomagnetic parameters

-major irregularities like SEDs and plasma bubbles can be
detected in midlatitudes

-June 7 decametric data clearly shows the evolution of an
irregularity that fits the characteristics of a plasma bubble over
Puerto Rico. Geomagnetic conditions were not remarkable.
  Radio Poetry
       by
John C. Mannone
   Plasma Bubbles
The furious light sinks below
And air above is tempered so

And not just anywhere this air
But somewhere in equator’s care

The daytime heated air is trapped
While colder air on top is zapped

Which tampered atoms’ state of rest
And left as ions their new guest

Hapless misty heavy layer
Grows a wave of Rayleigh-Taylor
At first a ripple, then a wave
Which drive unstable air to crave

The upper reaches-- freedom bound
The bubbles soar to higher ground

Peculiar pockets rising fast
The air had seen a solar blast

Holes large left with charge in trouble
Rising high as plasma bubbles

Gently urged by E cross B
These fickle fields that they do see
Not seen with ocular bore
But quivers in the radio floor

Bubbled pockets confuse the ray
Frantically bend it everyway

And when still dark and very late
The plasma plumes do dissipate

No longer there in hassling poise
The radio whispers quite noise.



By John C. Mannone
April 30, 2004
            Credits



University of Puerto Rico
Wanda Diaz

Tamke-Allan Observatory
David Fields

NASA/Radio Jove Project
Jim Thieman, Chuck Higgins, Leonard Garcia



          And many others, but especially…
… My Lord, Jesus the Christ
                 APPENDIX
              MISCELLANEOUS
ARTICLES, RESOURCES, AND EXPANDED DETAILS
A Few FFT Basics
The Fourier Transform, FT is an
analog tool used to analyze the
frequency content of continuous
signals.

The Discrete Fourier Transform,
DFT is a digital tool used to analyze
the frequency content of discrete
signals.

The Fast Fourier Transform, FFT is
an algorithm to rapidly compute the
DFT.
                              N = total number of discrete samples
                              T = total sampling time; don’t confuse with period
                              Dt = time increment between samples = T/N
                              fs = the sampling frequency = 1/Dt

                              N is often restricted to powers of 2
Digitizing the analog signal must be frequent to faithfully reproduce it.

Nyquist criterion fsampling > 2fmaximum (Image processing considerations
of brightness and contrast suggest a factor of 2.57).

Aliasing (fold-over or mixing) occurs if Nyquist sampling is violated.

                       ALIASING EXAMPLES

(1) Analog electronics: heterodyning is used for tuning; anti-aliasing
filters (low pass) filter unwanted signals before the A/D conversion.

(2) Engine timing: slow sampling by a strobe light can arrest the motion
of a rotating engine.

(3) Movie making: frames per second may be too slow and “wagon
wheels” will appear to stop or rotate backwards.

(4) Moiré patterns: slight motion of one of two overlapping
(semitransparent) repetitive patterns creates large scale changes in
patterns.
               Fourier Transform Examples




Also Gaussian pulse transforms to a Gaussian frequency
Random noise can be modeled as a series of spikes (think of a train of very
narrow Gaussians); transforms to huge Gaussian peak due to additive effect and
a noisy tail)
            Spectral Features Revealed
               Power vs. Frequency Plot


Dynamic nature of the ionosphere as well as the history of
travel through multiple media affecting the radio wave
leads to combs, bands, modulation envelopes. Visualize
Moiré patterns from multiple screen models.


Excited cavity modes and other ringing lead to resonant
lines: fundamental vibration and its harmonics.


Nonlinear interaction between boundaries may lead to
subharmonics.
Radio Jove Archive


    Comparative
  Solar Burst Data
 SC, MI, NM, MT, HI
March 26, 2002 22:23 Z


 Time & Frequency
 Analyzed in Excel
                   Radio Noise Floor
            log Power vs. log Frequency Plot


The spectral features are superimposed on a radio sky
background.


The behavior of this floor is an indicator of the state of the
media the radio wave propagates through.


Log-log plots reveal spectral index.
               HAARP 30 MHz VHF RIOMETER




HIGH FREQUENCY ACTIVE AURORAL RESEARCH PROGRAM


2 x 2 array of 5-element yagi antennas &
very sensitive low noise receiver
Flares and Prominences
Solar flares are tremendous explosions on the surface of the Sun. A billion
megatons of TNT energy release across the entire electromagnetic spectrum in
just a few minutes.
Coronal Mass Ejections
TH

Disruption of flow of the solar wind, compresses magnetopause
magnetic fields

dB/dt => strong currents induced on power grid

Coronal mass ejections are often associated with solar flares and
prominence eruptions but they can also occur in the absence of
either of these processes.
       Space Weather Forecasting

Measurement and Modeling Requirements


Living with a Star Measurements Workshop
       NASA Goddard Space Center

          February 9-10, 2000

             Gary Heckman

    NOAA Space Environment Center




                        NOAA SPACE ENVIRONMENT CENTER
                     SEC Users


Space Weather
Domain

Ionosphere


Geomagnetic field


Atmospheric
 density
Energetic particle
  environment



                            NOAA SPACE ENVIRONMENT CENTER
NOAA SPACE ENVIRONMENT CENTER
Products




           NOAA SPACE ENVIRONMENT CENTER
               Solar activity evolution--observations and models


                                                   Observing and Modeling
                                                       Requirements
Sun


      Interplanetary                                          Energetic particles
        disturbance
        initiation


                                                                   Earth
                       Interplanetary
                         observations


            Interplanetary/magnetosphere
              interaction models


In-situ observations and models within each domain
                                             NOAA SPACE ENVIRONMENT CENTER
Verification is a critical function




                    NOAA SPACE ENVIRONMENT CENTER
            Solar Measurement Priorities




• CME initiation in 3 dimensions to drive interplanetary models
         Direction
         Radial velocity
         Structure and configuration

• Coronal Holes—observation and prediction of Earth impact

• EUV/X-ray flux—observation and prediction

• Evidence of energetic particle acceleration and interplanetary injection

• X-ray flares and radio bursts—observation and forecasting

• Evolution of active structures--prediction

• Cycle evolution--prediction

                                           NOAA SPACE ENVIRONMENT CENTER
NOAA SPACE ENVIRONMENT CENTER
             Equatorial Scintillation                                C/NOFS                                        C/NOFS Ops

     Polar-Orbit Sun Synchronous            DMSP/POES                                                                            NPOESS

          Solar X-ray/EUV sensors           GOES XRS           Hard X-ray spectrometer     GOES EUV
           Solar X-ray/EUV Imager           YOHKOH       EIT     SXI                                                           Ops EIT
                 Solar Coronagraph         LASCO                 SMEI                                                          Ops CORONAGRAPH

     Solar Wind on Sun-Earth line          ACE

Particles and Fields (LEO to GEO to HEO)    GOES               DSP                             CEASE
                      Auroral Imager        IMAGE                                                                             Ops IMAGE

             Stereo Solar Observer                                     STEREO                                      Japan L5          STEREO VIEWER
                     GPS Occultation                                                                   COSMIC                            GPS/OCCULTER

  Scintillation--Polar and Low Lat                     SCINDA                                                             Ops SCINDA
                      TEC Networks         JPL Net                     FSL Net                                                   Ops TEC NET

               Ionosonde Sounders           IONOSONDES

          Magnetometer Networks             USGS/INTERMAGNET                             INTERMAGNET UPGRADES

                     All Sky Cameras                                                                                 ALL SKY Ops SYSTEM
                Solar Optical/Radio         SOON/RSTN          ISOON/SRBL/SRS
                     Riometer Chain         Thule                                                                                        Ops Riometer

              Ground-based radars                                     SuperDARN Radars

        Satellite Drag Observation                                                                                              DRAG Observer




                                   1999                                                       2004                                                      2009
                                                                                                                                                  Fully Capable Operational System
           R and D                     Less than fully capable operational system                        Observing Gap
                                                                                                                                                  Operational, funded, or planned
                                                                                           Early stages of definition or distance into future
                                Planned but doubt about deployment                                    NOAA SPACE ENVIRONMENT
                                                                                           lessens confidence of deployment, or no funding      CENTER
                                         Space Weather Operational Sensors Timeline

       Equatorial Scintillation                  C/NOFS           C/NOFS Ops
Polar-Orbit Sun Synchronous             DMSP/POES                NPOESS
                                        YOHKOH EIT   SXI              Ops EIT                                   Solar Polar Imager
     Solar X-ray/EUV Imager                                           Ops CORONAGRAPH
                                        LASCO
          Solar Coronagraph             AC                  Solar Wind Monitor                                          Solar Wind SENTRY
Solar Wind on Sun-Earth line            E
                                        GOES DSP GOES n/qCEASE                                                  Magnetospheric Constellation
 Particle Detectors (LEO to GEO to      IMAGE                       Ops IMAGE
                                 HEO)
                                                  STEREO Japan L5          STEREO VIEWER
                                                             COSMIC        GPS/OCCULT
                 Auroral Imager
                                                    SCINDA         Ops SCINDA
        Stereo Solar Observer                    JPL Net           Ops TEC NET
               GPS Occultation          IONOSONDES
   Scintillation--Polar and Low         USGS          INTERMAGNET UPGRADES

                             Lat                               ALL SKY Ops SYSTEM
                                        SOON/RSTN ISOON/SRBL/SRS
                  TEC Networks
                                        Thule                         OPS Riometer
           Ionosonde Sounders                                      DRAG Observer
     Magnetometer Networks
               All Sky Cameras
             Solar Optical/Radio
                Riometer Chain
    Satellite Drag Observation

            R and D                  Less than fully capable operational system            Observing                                 Fully Capable Operational System
                                                                                          Gap
                NOAA current, planned, or potential sensor or satellite set of sensors (e.g. GOES = GOES SEM)

Note: this version of the plan has not incorporated sensors from the NASA-interagency initiative Living with a Star




                                                                                            NOAA SPACE ENVIRONMENT CENTER
New Operational Measurement Priorities




                       NOAA SPACE ENVIRONMENT CENTER
NOAA SPACE ENVIRONMENT CENTER
NOAA SPACE ENVIRONMENT CENTER
NOAA SPACE ENVIRONMENT CENTER
NOAA SPACE ENVIRONMENT CENTER
NOAA SPACE ENVIRONMENT CENTER
NOAA SPACE ENVIRONMENT CENTER
             Radio Astronomy Web Resources

Society for Amateur Radio Astronomers (SARA)
NASA Project Radio Jove
Space Physics & Aeronomy on the Web

               SOLAR DATA RESOURCES

(1) A compilation of useful SOHO and GEOS satellite data
    are found at "Solar Physics on the Web." Below is a solar
    storm and geomagnetic storm monitor from the site and a
    link to it which shows current x-ray and particle flux as
    well as other data like magnetometer readings. From

   Solar X-ray & Geomagnetic Storm Monitor
(2) A comprehensive listing of NASA space-borne
laboratories (ACE, Cluster, FAST, IMAGE, Polar, RHESSI,
SAMPEX, SOHO, TIMED, TRACE, Ulysses, Voyager, and
Wind) is extractable from the Sun-Earth Connection Data
Availability Catalog Mission Overview Matrix. This is an
extremely useful table and links to project descriptions and to
live and archived data.

SECDAC Mission Overview Matrix
A useful item in the matrix is the link to various homepages
and mission matrices for each of the above. These in turn
have links to real-time data as well as to archived data. For
example,

(3) Follow the links to the WIND spacecraft/WAVES
instrument package/Waves homepage for electronic data
products. Useful spectrograms of 20-14,000 KHz radio
emissions are available from 1994 as well a a listing of Type
II & IV solar burst events:

WIND Daily Spectrogram Plots and Type II & IV Solar Burst
Lists
(4) Follow the links from the overview matrix to, say,
SOHO/GONG/. It will show all the available SOHO data:

SOHO Data

Near Real Time Images and Movies, which features 3 of the 12
SOHO instruments:

       EIT (Extreme UV Imaging Telescope)
       MDI (Michelson-Doppler Imager) Continuum and
       Magnetogram
       LASCO (Low Angle and Spectrometric Coronagraph
       Experiment)

(4a) The latest solar images with these instruments are found on

The Sun Now
(4b) From the SOHO Data page, choose the specific
instruments under "Other Near Real Time Data," which
represent other instruments aboard SOHO:

       -VIRGO (Variability of Solar Irradiance and Gravity
       Oscillations)
       -Total Solar Irradiance
       -CELIAS (Charge, Element and Isotope Analysis
       System)
       -Proton and Energetic Particle Flare Activity
       Monitors, X-ray Flare Monitor
       -ERNE (Energetic and Relativistic Nuclei and
       Electron) Proton and Helium Intensity
       -MDI Far Side Imaging
       -SWAN ((Solar Wind Anisotropies) Far Side Imaging

For a description of the 12 SOHO Instruments, see the link
below: SOHO Instruments
(4c) SOHO Data page also has the "Other Near Real Time
Data" list, which has the particularly useful
"Solar/Heliospheric Forecast" and "Recent Solar Activity"
subheadings.

(5) Solar/Heliospheric Forecast has many good products
including Solar wind model and Virtual Star Lab:

Solar & Heliospheric Weather Model (IMSAL)

(6) From here, the Solar Data link is Solar Physics on the
Web, which has comprehensive live and easy-to-use archive
database (SOHO, GOES, WIND and the MEES Solar
Observatory in Hawaii). Recommend to have some of these
open when collecting Radio Jove data.

Solar Physics on the Web
(7) Recent Solar Activity: pinpoint the sunspot group that was
active. Choose an event in the time span given, perhaps the
strongest X-ray flare (in order of increasing intensity: A, B, C,
M, X)

Solarsoft (Lockheed Martin Solar and Astrophysics Laboratory)

Header Information: Event Number, GOES Flare Classification,
etc.

Flare sequence images (JavaScript frames w/ GOES flux plotted
above)

TRACE event sequences 171A images (JavaScript, GIF
Animations, or MPEGs), and Flare locator image

Latest Solar Events
(8) Archived data (item 7) is harder to come by. Solarsoft is
developing access to the database. However, the GOES data
is easily retrievable back to 1991 from their Yohkoh solar x-
ray telescope database:

Yohkoh GOES Data Base Browser

(9) IPS Radio and Space Services provides several excellent
resources under their "Space Weather" and "Solar" links.
Real time Coolgura (18-1800 MHz) and Learmonth (25-180
MHz) Spectrograms as well as daily historical data up to 3
months (Coolgora). Space weather and ionospheric data is
also provided.

Australian Space Weather Agency
           COMPLEMENTARY RESOURCES

(1) A series of graduate level lectures on plasma physics:
    International Max Planck Research School on Physical
    Processes in the Solar System and Beyond at the
    Universities of Göttingen and Braunschweig.

Solar System School

(2) Ground based facilities, like the Alaskan High Frequency
    Active Auroral Research Program (HAARP). Ionospheric
    data (real time and archived) is available under the
    various instruments (Magnetometer, Riometer, HF
    Ionosound, Total Electron Content, Spectrum Monitor,
    etc.). See "Scientific Data from the Site" in the Table of
    Contents below,

HAARP Table of Contents
(3) Services, like those of Northwest Research Associates
(NWRA) Space Weather and Ionospheric Scintillation
Predictions. Very helpful staff. Site has good links to
tutorials.

Space Weather Services
Ionospheric Scintillation Predictions

(4) Products from several weather and lightning satellite
databases.

Aviation Digital Data Service
Vaisala Lightning Explorer
(5) Some climatological data to be displayed on a 3-
dimensional globe that one can manipulate (a good option
but may require a free software download). (to 1995):

The GLOBE Program

Images provided by Weather Services International Corp.
(WSI) and NASA though the Global Energy and Water Cycle
Experiment Continental-Scale International Project.
Currently Available
1 April 1995 to 18 April 1997, Daily
19 April 1997 to 29 May 2004, Hourly
Select the Radar product in the link below:

NEXRAD Archived Radar
(6) Specialized Databases like the 81.5 MHz Interplanetary
Scintillation. Some animations are available for 1990-1993.

Interplanetary Scintillation (IPS) Data
IPS Hammer-Aitoff Projection March 1992

(7) Prediction of Jupiter storms is based on the interaction of
the Jovian moon, Io, with the Jovian magnetic field.
Professor Kazumasa Imai (Kochi National College of
Technology, Department of Electrical Engineering) has
prepared a useful prediction tool. This will prove invaluable
to assess the potential influence of certain Jovian storms
occurring concurrently with a solar burst (this speculation
will be defended later).

The Jovian Daily Ephemeris
(8) Solar and Jovian data files from October 1999 (mostly
decametric) can be accessed via the link on the Radio Jove
homepage (above). It can be directly accessed via "View
Current Data Archive," which allows one to specify the fields
to view (be sure to mark "Data Products").

Radio Jove Data Archive

(9) Other than to look at picture files of the signal traces in
the archive, one will need the SPD wave files to manipulate
the data. Radio Sky Publishing has free PC software that
allows strip chart recording and sharing files over the
internet. The affordable Pro version may be required for
some features, like converting the SPD files to TEXT files
which can be manipulated in EXCEL.

Radio Sky Publishing/SkyPipe Software
(10) Planetarium software

Starry Night Planetarium Software
Cartes du Ciel (Sky Charts)
SEDS Planetarium Software List

(11) Geographical Information is obtained from several
databases when the planetarium software falls short:

USGS Geographic Names Information System
Topographical Maps & Coordinates (Topozone)
Maporama: Lat/Lon for Specific Location
(12) Astronomical information

Greenwich Sidereal Time Calculator (Astro Java)

(13) Geomagnetic Latitude and Longitude

Convert Geographic to Geomagnetic Coordinates
Recorded Radio Signal Differences Explained

Receivers
      Design
      Electronic Noise
      Calibration

Antennas
      Frequency
      Antenna Pattern
      Location
             Local Obstructions
             Geographic Coordinates
      Ground Capacitance
             Distance Above Ground
             Soil Type
      Calibration
Recorded Radio Signal Differences Explained

Transmission Lines
              Impedance Mismatch
              Microphonic Cable/Wind Loading

Man-made Interferences
             Power Lines
             Cycling Electrical Equipment (motors)
             Transmitters (Radio, TV, proposed digital
                           phone lines…)
Recorded Radio Signal Differences Explained

Natural Interferences and Phenomena
       Atmosphere
               Lightning
               Weather
       Ionosphere
               Radio Twinkling
       Magnetopause
               Shocks
               Schumann Resonances (VLF Earth Cavity)
       Corona
               Coronal Loop Oscillations
               Plasma Instabilities
       Photosphere/Flares/Prominences
               Bunching/Stretching Magnetic Field Lines
       Solar Cavity
               Resonant “Acoustics”
               Tropospheric Scintillation


-Scintillation
   A rapid fluctuation in amplitude, phase and arrival angle

-Refractive Index
  Small irregularities caused by temperature inversions
  i.e., reverse of lapse rate due to:
  trade wind inversion, frontal inversion,turbulent boundary
                Tropospheric Scintillation
-Dry Scintillation: no fading
-Wet Scintillation: causes fading when raining
Absorption Bands
Elevation angle 90°
Latitude 45°N

Water Vapour
22.2, 182 and 325 GHz

Oxygen
60 and 119 GHz

Small losses < 10 GHz
The ionosphere, the closest naturally occurring plasma.

Signals transmitted to and from satellites for communication and
navigation purposes must pass through the irregularities in the
ionosphere (most common at equatorial latitudes, although they
can occur anywhere)

Computer simulations of ionospheric processes (ionospheric
model developed at the University of Alaska, Fairbanks.) The
development of visualizations of this type have allowed us to see
and appreciate the enormous variability and turbulence that
occurs in the ionosphere during a major solar geomagnetic
storm.

Adapted from “The Importance of Ionospheric Research”
http://www.haarp.alaska.edu/haarp/ion2.html
VHF Satellite Scintillation
ANTENNA     SLOPE OF     SLOPE OF     CORNER    IONOSPHERE
LOCATION    FIRST        SECOND       FREQUENCY
            SEGMENT      SEGMENT      mHz
Receiver    0            -            -              No bias
Noise
SC          0            -0.59        224            Normal Radio
                                                     Sky
MI          0            -1.05        363            Off-normal

NM          -1.25        0            227            Weak
                                                     Scintillation
MT          -2.48        0            413            Classic
                                                     Scintillation

HI          -4.67        -0.98        130            Strong
                                                     Scintillation

           March 26, 2002 Solar Burst Event 21:23Z
Excerpt prepared for NASA Radio Jove Bulletin; full details on my
web site Adventures in Astronomy by John C. Mannone

            The Solar-Ionospheric Connection: Physics
                      with the 20 MHz Antenna
At the 2003 SARA Conference, I discussed the increased utility of
the 20 MHz radio telescopes. Systems, such as Radio Jove, can be
an interesting probe for both solar physics and geophysics. A
variety of resources are used to compare antenna signals
originating from the sun. Simultaneous records from several
different locations show similar gross features. However, there are
differing finer details that present a challenge to reconcile. My new
web page, http://home.earthlink.net/~jcmannone/, presents some
very useful resources (Radio Astronomy Web Tools) that benefit
any effort to understand comparisons of solar bursts (or Jovian
storms).
In addition to these comparison tools, a frequency analysis of
the antenna signals will reveal even more. There are many
things that will affect a radio wave in its path to your
antenna. Most notably is turbulence. It causes fluctuations in
the solar wind and in our ionosphere. In turn, they cause the
radio wave to fluctuate. Even upper level winds in our
atmosphere can affect the radio wave in the same way
starlight is made to twinkle.

These different kinds of twinkle can be studied by signal
processing methods available in Microsoft Excel. The
mathematic tool is called an FFT from which a power
spectrum is plotted. It reveals these effects on the radio wave
and points to the physics causing it.
Radio twinkling is usually studied with more sophisticated
equipment and at much high frequencies (~250-1700 MHz)
because of their importance in communication, navigation,
and pulsar research. The exciting thing here is exploration of
“new ground” with the 20 MHz systems; and, we have a
virtual global antenna farm to do it with.

				
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