Tag Archives: sunspots

New Coronal Hole

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CORONAL HOLE: NASA’s Solar Dynamics Observatory is monitoring a coronal hole in the sun’s northern hemisphere. It is the UV-dark region in this image taken during the early hours of Sept. 21st:

The white lines in the image trace the sun’s magnetic field. A coronal hole is a place where the magnetic field spreads apart, allowing solar wind to escape. A stream of solar wind flowing from this particular coronal hole is heading for Earth, due to arrive on Sept. 23-24. Its arrival could add to the impact of a minor CME expected to reach Earth at about the same time. Polar geomagnetic storms are possible early next week.

fr/spaceweather.com

New Sunspot Activity

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BREAK IN THE QUIET: Solar activity has been low for weeks. The emergence of sunspots AR1817 and AR1818 could break the quiet. Both pose a threat for M-class solar flares. AR1817 has already produced one almost-M class eruption:

The C8-category flare was recorded by NASA’s Solar Dynamics Observatory on August 11th at 2158 UT. Whether it is a herald of bigger things to come remains to be seen. AR1817 is almost directly facing Earth, so any eruptions this week will probably be geoeffective.

fr/spaceweather.com

Solar Storms Possible

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CHANCE OF STORMS: NOAA forecastesrs estimate a 65% chance of polar geomagnetic storms on August 10th when one and perhaps two CMEs are expected to hit Earth’s magnetic field. The incoming clouds were propelled from the sun by a flurry of erupting magnetic filaments on Aug. 6-7. High-latitude sky watchers should be alert for auroras.

fr/spaceweather.com

Large Sunspot Eruptions

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BIG SUNSPOT FACES EARTH: Colossal sunspot AR1785 is now directly facing Earth. The active region has a ‘beta-gamma-delta’ magnetic field that harbors energy for X-class flares, yet so far the sunspot has been mostly quiet. Could it be the calm before the storm? NOAA forecasters estimate a 55% chance of M-flares and a 10% chance of X-flares on July 8th.

Sprawling more than 11 Earth-diameters from end to end, AR1785 is one of the biggest sunspots of the current solar cycle. In fact, it can barely fit on the screen. Click on the dark core below to see a complete hi-res picture taken by Christian Viladrich of Nattages, France:

To take the picture, Viladrich used a filtered 14-inch Celestron telescope. All those irregular blobs surrounding the primary dark core are boiling granules of plasma as small as the state of California or Texas. It’s a very sharp picture.

from: spaceweather.com

Geomagnetic Storm

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GEOMAGNETIC STORM: A G1-class (Kp=5) geomagnetic storm is in progress following the arrival of an interplanetary shock wave on May 31st. The source of the shock is not known; it might have been a minor CME that left the sun without drawing attention to itself. The impact sparked auroras across many northern-tier US states. This photo, for instance, comes from Christopher Griffith in Baxter, Minnesota:

“I wasn’t expecting to see any lights, but right before the midnight it broke loose and the sky lit up,” says Griffith. “Sadly the clouds quickly filled in my little window, and the auroras were gone. Just thankful for what I got so see!” Elsewhere in the USA, auroras were sighted as far south as Colorado, Maryland, Iowa, Wisconsin, and Nebraska.

High-latitude sky watchers should remain alert for auroras tonight as Earth’s magnetic field continues to reverberate from the impact. NOAA forecasters estimate a 40% chance of polar geomagnetic storms on June 1st.

from:   spaceweather.com

Incoming CME

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ANOTHER INCOMING CME: As Earth’s magnetic field reverberates from one CME strike, a second more potent CME is on the way. It was propelled in our direction by sunspot AR1748, which unleashed an M3-class solar flare on May 17th (0858 UT). Although this is not the strongest flare we’ve seen from AR1748, it could be the most geoeffective; the sunspot was almost-squarely facing Earth when the blast occurred. NOAA forecasters estimate a 75% chance of polar geomagnetic storms when the cloud arrives.

The Solar and Heliospheric Observatory took this picture of the CME leaving the sun at 1500 km/s (3.4 million mph) on May 17th:

In the video, the CME appears to hit Mercury, but it does not. It is merely passing in front of the innermost planet. The planet in the line of fire is actually Earth.

from:    spaceweather.com

More X-Flares

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X-FLARE THREAT CONTINUES: Sunspot AR1748 has already unleashed four X-class solar flares, but it might not be finished. The active region continues to grow beneath a delta-class magnetic field that harbors energy for powerful eruptions. NOAA puts the odds of another X-flare today at 60%. Solar flare alerts: text, voice.

NASA’s Solar Dynamics Observatory took this picture of AR1748 during the early hours of May 16th:

The sunspot is not particularly large, but it is complex, with many dark cores scattered through its zone of influence. This is a sign of a complicated overlying magnetic field. Magnetic complexity is the source of AR1748’s explosiveness: when tangled lines of magnetic force cross and reconnect–bang! A flare occurs.

All by itself, AR1748 has produced more X-flares than every other sunspot of the past year combined. In summary, AR1748 has given us an X1.7-class flare (0217 UT on May 13), an X2.8-class flare (1609 UT on May 13), an X3.2-class flare (0117 UT on May 14), and an X1-class flare (0152 on May 15). More could be in the offing.

fr/spaceweather.com

Two New Sunspots

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TWO NEW SUNSPOTS: On Friday they didn’t exist. On Saturday they are big sunspots. Today, sunspots AR1726 and AR1727 are rapidly emerging in the sun’s northern hemisphere. The larger of the two, AR1726, contains nearly a dozen dark cores and spans 125,000 km from end to end. Click to view a 24-hour movie recorded by NASA’s Solar Dynamics Observatory:

AR1726 is the fastest-growing and, so far, the most active. It is crackling with C-class flares and seems capable of producing even stronger M-class eruptions. Because of the sunspot’s central location on the solar disk, any explosions this weekend will be Earth-directed.

fr/spaceweather.com