Major Solar X-Flare Could Boost OTA DXing, Disrupt Telecom: July 12, 2012

[ota_canuck]

A major X flare just happened on the earth-facing side of the sun that could really create some tropo effects for the next 3 days or so. Happy tropo hunting!

Email I just received from spaceweather.com:

X-FLARE! Big sunspot AR1520 unleashed an X1.4-class solar flare on July 12th at 1653 UT. Because the sunspot was directly facing Earth at the time of the blast, this is a geoeffective event.

NASA's Solar Dynamics Observatory recorded a flash of extreme ultraviolet radiation from the blast site:

The UV and X-ray pulse from the flare will have partially ionized Earth's upper atmosphere on the dayside of our planet, disturbing the normal propagation of radio signals. Watch the Realtime Space Weather Gallery for possible reports of sudden ionospheric disturbances and other effects.

2012-07-12 17:14 UTC R3-Radio Blackout Storm in Effect

R3-Radio Blackout Storms (Strong) are currently in effect. Region 1520, located close to center disk, is the culprit on today's events. It is still to early to see if an Earth-directed CME or energetic particles are associated with this event, however SWPC forecasters are monitoring the situation. Stay tuned for further information on this event and other Space Weather news.

Warning Condition: Onset
Potential Impacts: An enhancement in the energetic portion of the solar radiation spectrum may indicate increased biological risk to astronauts or passengers and crew in high latitude, high altitude flights. Additionally, energetic particles may represent an increased risk to all satellite systems susceptible to single event effects. This information should be used in conjunction with the current Solar Radiation Storm conditions when assessing overall impact.

This could prove to be an interesting few days of propogation mahem!

[tvlurker]

Sunspots may increase the probability of Sporadic E-Skip, not tropospheric ducting.

Look for log distance propagation of VHF-Low and FM signals.

[ota_canuck]

Not just skip, but general powerful disturbances of normal propagation of radio signals.

The UV and X-ray pulse from the flare will have partially ionized Earth's upper atmosphere on the dayside of our planet, disturbing the normal propagation of radio signals.

This charged upper atmosphere could linger for 3 or more days.

So after a very solar-active week just past us with some extreme tropo being reported in this forum,.. and now some extreme solar activity, the point of my posting about today's solar activity is that it may explain why in recent days there have been some stranger than usual tropo reported here. So, possibly even stranger tropo could happen.

Here is one spectrum disturbance that was reported this afternoon @ 56.25Mhz
http://spaceweather.com/submissions/...2119593_lg.jpg

[stampeder]

Thanks for the update, ota_canuck! This will be very interesting to see.

[ota_canuck]

Just dropping off an update from http://www.swpc.noaa.gov/

2012-07-14 18:28 UTC Shock at ACE Spacecraft

The shock passed the ACE spacecraft at approximately 1730 UTC (1:30 p.m. EDT) today, July 14. Now watch for the CME and then, the imminent disturbance to the geomagnetic field. SWPC expects G1 (minor) and possibly G2 (moderate) geomagnetic storm levels over the next 36 hours. More as this unfolds.

Space Weather Message Code: WARK06
Serial Number: 199
Issue Time: 2012 Jul 14 1914 UTC

WARNING: Geomagnetic K-Index of 6 expected
Valid From: 2012 Jul 14 1915 UTC
Valid To: 2012 Jul 14 2359 UTC
Warning Condition: Onset
NOAA Scale: G2 - Moderate
Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

We will watch the forums tropo threads and see if any [IMF] Interplanetary Magnetic Field disturbances have any impact on reception disturbances and tropo propagation. Being that this is a very rare direct hit from a very fast moving CME coming from an X.1 solar flare, it will be one of strongest impacts in recent history and quite interesting to see the reception/propagation effects . The IMF impact surface instruments began fluctuating wildly at 4pm est. Could also lead up to a great light show tonight at dusk and early tomorrow morning before dawn.

Nasa says these strong X flares may become more frequent throughout the next 2 years until 2014. The question remains as to how many will be directly aimed at the earth.

[ota_canuck]

This strong solar event has almost wrapped up for now and there are a few observations regarding effects upon tropo vs regular reception issues. Despite this normally active summer tropo period, there appears to have been less tropo reports on the forum's tropo threads since the initial solar flare's 10cm radio burst event on the 12th and the following proton storm, and the solar geoeffective winds.

The initial radio burst on the afternoon of July 12th caused some significant 56Mhz disruptions for about an hour and since then there have been no noticable TV spectrum disruptions and very limited occurances of tropo propagation reported on this forum.

The past few days of having 'reliable 24/7 channel reception' for me has been absent of the usual strong summer tropo events that sometimes pixelate or wipe out my regular channels. The past days have seemed more like regular tropo free winter viewing conditions.