Strong Solar Storm Reaching Earth?

Sunspot 1302 has already produced two X-flares (X1.4 on Sept. 22 and X1.9 on Sept. 24th). Each of the dark cores in this image from SDO is larger than Earth, and the entire active region stretches more than 100,000 km from end to end. The sunspot's magnetic field is currently crackling with sub-X-class flares that could grow into larger eruptions as the sunspot continues to turn toward Earth. (Credit: NASA/SDO/HMI)

Sunspot 1302 Continues to Turn Toward Earth!!

A strong-to-severe (Kp=8) geomagnetic storm is in progress following the impact of a coronal mass ejection (CME) at approximately 8:15a.m. EDT (12:15 UT) on Sept. 26. The Goddard Space Weather Lab reported a strong compression of Earth's magnetosphere. Simulations indicate that solar wind plasma has penetrated close to geosynchronous orbit starting at 9am. Geosynchronous satellites could therefore be directly exposed to solar wind plasma and magnetic fields.

Behemoth sunspot 1302 unleashed another strong flare on Saturday morning -- an X1.9-category blast at 5:40 am EDT. NASA's Solar Dynamics Observatory (SDO) recorded the extreme ultraviolet flash.

NASA images showing a shadowy shock wave racing away from the blast site are a sign that the blast produced a coronal mass ejection (CME) that could deliver a glancing blow to Earth's magnetic field on Sept. 26.

Since the X1.9-flare, active region (AR) 1302 has unleashed M8.6 and M7.4 flares on Sept. 24 and an M8.8 flare early on Sept. 25. None of the blasts have been squarely Earth-directed, but this could change as the sunspot turns toward our planet in the days ahead. AR1302 is growing and shows no immediate signs of quieting down!!!!!!!

what is a solar flare?

A solar flare is an intense burst of radiation coming from the release of magnetic energy associated with sunspots. Flares are our solar system’s largest explosive events. They are seen as bright areas on the sun and they can last from minutes to hours. We typically see a solar flare by the photons (or light) it releases, at most every wavelength of the spectrum. The primary ways we monitor flares are in x-rays and optical light. Flares are also sites where particles (electrons, protons, and heavier particles) are accelerated.

What is a coronal mass ejection?

The outer solar atmosphere, the corona, is structured by strong magnetic fields. Where these fields are closed, often above sunspot groups, the confined solar atmosphere can suddenly and violently release bubbles of gas and magnetic fields called coronal mass ejections. A large CME can contain a billion tons of matter that can be accelerated to several million miles per hour in a spectacular explosion. Solar material streams out through the interplanetary medium, impacting any planet or spacecraft in its path. CMEs are sometimes associated with flares but can occur independently.

what is a sun spot?
Sunspots, dark areas on the solar surface, contain strong magnetic fields that are constantly shifting. A moderate-sized sunspot is about as large as the Earth. Sunspots form and dissipate over periods of days or weeks. They occur when strong magnetic fields emerge through the solar surface and allow the area to cool slightly, from a background value of 6000 ° C down to about 4200 ° C; this area appears as a dark spot in contrast with the very bright photosphere of the sun. The rotation of these sunspots can be seen on the solar surface; they take about 27 days to make a complete rotation as seen from Earth.

Sunspots remain more or less in place on the sun. Near the solar equator the surface rotates at a faster rate than near the solar poles. Groups of sunspots, especially those with complex magnetic field configurations, are often the sites of solar flares. Over the last 300 years, the average number of sunspots has regularly waxed and
waned in an 11-year (on average) solar or sunspot cycle.
Does all solar activity impact earth?

1]Solar flares impact Earth only when they occur on the side of the sun facing Earth. Because flares are made of photons, they travel out directly from the flare site, so if we can see the flare, we can be impacted by it.

2]Coronal mass ejections, also called CMEs, are large clouds of plasma and magnetic field that erupt from the sun. These clouds can erupt in any direction, and then continue on in that direction, plowing right through the solar wind. Only when the cloud is aimed at Earth will the CME hit Earth and therefore cause impacts.

3]Modern society depends on a variety of technologies susceptible to the extremes of space weather. Strong electrical currents driven along the Earth’s surface during auroral events disrupt electric power grids and contribute to the corrosion of oil and gas pipelines. Changes in the ionosphere during geomagnetic storms interfere with high-frequency radio communications and Global Positioning System (GPS) navigation. During polar cap absorption events caused by solar protons, radio communications can be compromised for commercial airliners on transpolar crossing routes. Exposure of spacecraft to energetic particles during solar energetic particle events and radiation belt enhancements cause temporary operational anomalies, damage critical electronics, degrade solar arrays, and blind optical systems such as imagers and star trackers.

4]Human and robotic explorers across the solar system are also affected by solar activity. Research has shown, in a worst-case scenario, astronauts exposed to solar particle radiation can reach their permissible exposure limits within hours of the onset of an event. Surface- to-orbit and surface-to-surface communications are sensitive to space weather storms.

1 comment:

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