May I please ask how the drift rate is calculated from spectra ?

I download the published image and open it with the GIMP open source image editor:
http://www.gimp.org/downloads/

I use the GIMP measurement tool to measure distances in pixels and slopes in degrees and:

Compute the frequency scale [pixels per MHz].
Compute the time scale [pixels per second].
Measure the slope angle from the time axis to the burst estimated center line (many times difficult to do).

Finally compute:
DriftRate[MHz/second] = TimeScale[pixels/second]/FrequencyScale[pixels/MHz]*Tangent(SlopeAngle)
and write it in the summary and histogram.

There is another method described by Jim Sky on 130320, in a message to the Radio Jove Data list:

"...Hi Victor and All,

Radio-Sky Spectrograph (RSS) has a built in tool for measuring drift rates of features seen on the spectra.  Unfortunately, the help for RSS is woefully out of date.

The tool works with saved sps files in Stand Alone mode.
Load the chart and then place the mouse pointer at one end if the feature. Press the Right mouse button and  select Find Slope Between Points.

Now click on the other end of the feature (it does not matter which end you click first).  Below is a screen shot of the result of measuring a sweeper (ionosonde) using this method.  The result actually is drawn on the chart automatically.  This slope is +133 kHz/sec

Jim Sky..."

You may also use a power versus time graphic, for two frequencies, and measure the time difference. Whitham D. Reeve frequently publishes very good charts with 20.339 (red) and 32.537 (green), delta = 12.198 MHz, data.

Summary of recent solar drift rates

yymmdd hhmm UTC, Author, negative drift MHz/s

Type III


130430 1856 Ashcraft       1.0
130428 1633 Reeve          4.8
130413 1552 Reeve          3.1
130402 1558 Reeve          5.2
130330 2202 Flagg          >10
130320 1803 Flagg          2 
130320 1803 Typinski       3.8
130320 1803 Greenman       0.5
130320 1803 Reeve          0.4
130317 1806 Typinski       5.4
130316 1906 Typinski       7.4
130316 1903 Greenman       1.1

Histogram of the type III drift rate distribution, in 1 MHz/s bins:

0 xx
1 xx
2 x
3 xx
4 x
5 xx
6
7 x

Type II

130418 1832 Typinski      0.034
130330 1324 Nancay        0.06

Many thanks to the Authors.
 

J130425 -- Three Io-A arcs (red pass) at Nancay

Many thanks to the Taxpayers of France, and the Nancay Decametric Array Team at the Nancay Radio Astronomy Station of Paris Observatory.

I-LOFAR - Exploring the Universe from Ireland

http://www.lofar.ie/

Sonification for the visually impaired

Solar and Jovian radiation can be sonified:
http://radiojove.gsfc.nasa.gov/library/newsletters/2006Nov/#5
http://radiosky.com/sonification.htm

Many thanks to Jim Sky for developing sonification tools.

My Friend Wanda describes how losing her sight led her to investigate new ways of studying space physics, using sound rather than visual information:
http://www.iop.org/careers/workinglife/articles/page_51170.html

http://www.physicstoday.org/resource/1/phtoad/v65/i5/p20_s1?bypassSSO=1

http://cse.ssl.berkeley.edu/stereo_solarwind/sounds_links.html

Sonification Handbook Chapter 12:
http://sonification.de/handbook/download/TheSonificationHandbook-chapter12.pdf

Diaz-Merced et al. 2008, Sonification for the Analysis of Plasma Bubbles at 21 MHz
http://www.shao.az/SG/v3n1/SG_v3_No1_2008-p-42.pdf

Touch of The Universe Project:
http://astrokit.uv.es/
http://astrokit.uv.es/gallery.html

"...The beauty of the Universe never fails to amaze us. From poets, artists to astronomers and public, we all have been fascinated by its beauty. But, take a step back and think! What about people with vision impairments?

According to the World Health Organisation, about 285 million people have some degree of visual impairment. About 39 million are blind, and 246 million are visually impaired. About 90% of them live in developing countries of Africa, Asia, Latin America and the Pacific Regions, and they are 10 times more likely to go blind than those in developed countries.

To address this much neglected area, under the framework of Universal Design of Learning (UDL), we have created 'A Touch of The Universe' project. It aims to build 30 sets of tactile astronomy KITS for children with vision impairments. But we need your support to complete the project.

If you would like to support the project, you can make a donation on the project's website. You can also support the project by circulating the call amongst your friends, promoting it on your social media networks and blogging about it..."

130421 -- Wonderful selected solar activity at Nancay

130421 -- Wonderful selected solar activity at Nancay


Many thanks to the Taxpayers of France, Nancay Decametric Array Team at the Nancay Radio Astronomy Station of Paris Observatory, Solar Dynamics Observatory, and Solar Monitor at Trinity College in Dublin Ireland.

Sun 130413-130417, types I III and continuum, at Nancay

Sun 130413-130417, types I III and continuum, at Nancay

Many thanks to the Taxpayers of France, and the Nancay Decametric Array Team at the Nancay Radio Astronomy Station of Paris Observatory.



 
130414 two spectra below

 

S130411 -- M6.5 flare in AR 11719 followed by strong radio burst

 S130411 -- M6.5 flare in AR 11719 followed by strong radio burst, with types II and IV radiation, Earth directed CME, Moreton wave

At Learmonth Observatory, Australia:
2700 sfu 245 MHz
3000 sfu 1.415 GHz
100 sfu 15.4 GHz

This flare generated a wonderful type IV display at Nancay, in right and left circular polarizations, strongest in RCP, reaching 20 dB above background, 25 to 65 MHz band. Please see selected Nancay spectra below.

Many thanks to SDO, SOHO, LMSAL, Learmonth Observatory,  e-Callisto Solar Observatories in Ireland and Germany:
http://herrero-radio-astronomy.blogspot.com/search/label/e-Callisto 
the Taxpayers of France, and the Nancay Decametric Array Team at the Nancay Radio Astronomy Station of Paris Observatory.

SOHO CME images below

Nancay spectra below

SDO image below

130308 Io-B - ionospheric electron concentration change rate from Mount 2013 04 09 publication

I analyze Mount's published spectrum and measure:

Drift rate ~  -1.4E-3 MHz/s at 21 MHz on 130308 0130 UTC
Relative drift rate = -6.7E-5 per second

Relative ionospheric electron concentration change rate ~ -1.3E-4 per  second ~ - 0.78 % per minute

More about ionospheric modulations at:
http://herrero-radio-astronomy.blogspot.com/search/label/Ionospheric%20Modulations

Many thanks to Andy for his publication.

S130403-130407 -- Interesting 40 minute long type VI at Nancay

11 active regions today 130407.

The type VI (long series of type IIIs) reached 30 dBab, LCP about 10 dB stronger than RCP:

Studying the Hinode XRT image for 130406, my favoured suspect for this activity would be AR 11718, which produced 8 C flares in 2 days, has an 18% chance of M flares, and Class Beta/Gama Dsi.

Many thanks to the Nancay Decametric Array Team at the Nancay Radio Astronomy Station of Paris Observatory, Hinode and Trinity College Dublin.





130407 below

130404-130405 -- Plenty of weak activity, below 10 dBab

AR 11711 is still the largest, 5.8E-4 hemisphere, class Beta Cko, 6% M flare probabilty.

Many thanks to the Taxpayers of France, and the Nancay Decametric Array Team at the Nancay Radio Astronomy Station of Paris Observatory.

130405 below

Below 130403 -- 8 hours of weak type III bursts, several per minute, less than 10 dB above background
http://www.swpc.noaa.gov/ftpdir/indices/events/20130403events.txt

I blame AR 11711 for most of the action:
http://www.solarmonitor.org/region.php?date=20130403&region=11711

http://www.solarmonitor.org/data/2013/04/03/pngs/hxrt/hxrt_flter_ar_11711_20130402_060342.png

Many thanks to Trinity College Dublin - The University of Dublin:
http://www.tcd.ie/
the Taxpayers of France, and the Nancay Decametric Array Team at the Nancay Radio Astronomy Station of Paris Observatory.