Category Archives: Space Weather

Sunspots are in short supply (and it’s only getting worse)

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Not a sunspot to be found. (Credit: SDO/HMI via Spaceweather.com)

Unfortunately, this is not news to brighten your day. According to Spaceweather.com, sunspots are disappearing faster than expected:

Sunspots are becoming scarce. Very scarce. So far in 2018 the sun has been blank almost 60% of the time, with whole weeks going by without sunspots. Today’s sun, shown here in an image [above] from NASA’s Solar Dynamics Observatory, is typical of the featureless solar disk.

The fact that sunspots are vanishing comes as no surprise. Forecasters have been saying for years that this would happen as the current solar cycle (“solar cycle 24”) comes to an end. The surprise is how fast.

“Solar cycle 24 is declining more quickly than forecast,” stated NOAA’s Space Weather Prediction Center on April 26th. This plot shows observed sunspot numbers in blue vs. the official forecast in red:

“The smoothed, predicted sunspot number for April-May 2018 is about 15,” says NOAA. “However, the actual monthly values have been lower.”

Continue reading the full story at Spaceweather.com.

I will be very happy to see sunspot numbers rise again–they eventually will, of course. I’ve almost forgotten what a proper band opening feels like.

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A second magnetic field discovered

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(Source: Southgate ARC)

The ESA just discovered a second magnetic field surrounding our planet

A trio of satellites studying our planet’s magnetic field have shown details of the steady swell of a magnetic field produced by the ocean’s tides.

Four years of data collected by the European Space Agency’s (ESA) Swarm mission have contributed to the mapping of this ‘other’ magnetic field, one that could help us build better models around global warming.

Physicist Nils Olsen from the Technical University of Denmark presented the surprising results at this year’s European Geosciences Union meeting in Vienna, explaining how his team of researchers managed to detail such a faint signature.

“It’s a really tiny magnetic field,” Olsen told BBC correspondent Jonathan Amos. “It’s about 2 – 2.5 nanotesla at satellite altitude, which is about 20,000 times weaker than Earth’s global magnetic field.”

On a fundamental level, both fields are the result of a dynamo effect produced by charged particles being sloshed around in a fluid.

The stronger magnetic field that tugs on our compass needle forms from the steady movement of molten rock deep under our feet.

This field also leaves its signature in the alignment of particles embedded in Earth’s crust, a pattern that has also been analysed in detail by Swarm

Read the full story at:
https://www.sciencealert.com/esa-swarm-satellite-map-ocean-tides-magnetic-field

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Space Weather: A [big] Hole in the Sun’s Atmosphere

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The SWLing Post Blog has recently featured a few posts on “Space Weather” & Geomagnetic Storms. As an amateur astronomer, I receive many daily space-related emails in my INBOX right along with the SWLing Post Daily Digest. I thought this might be of interest:

From Spaceweather.com

An unusually wide hole in the sun’s atmosphere is facing Earth and spewing a stream of solar wind toward our planet. Estimated time of arrival: April 9th. Polar geomagnetic unrest and minor G1-class storms are possible when the gaseous material reaches Earth. Visit Spaceweather.com for more information and updates.

Image credit: NASA’s Solar Dynamics Observatory.

The hole bisects half the solar disk, stretching more than 700,000 km from end to end. This means Earth will be under the influence of the emerging solar wind stream for more than 4 days after it arrives.

A G1-class storm is “Minor”, so I doubt there will be very much “radio” impact – but you gotta admit, a hole that large is interesting nonetheless!

Posted by SWLing Post Contributor Troy Riedel

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Vernal equinox ‘cracks’ in Earth’s magnetic field

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Credit: NOAA SWPC

(Source: Southgate ARC)

Equinox ‘cracks’ forming in Earth’s magnetic field

The vernal equinox is less than 10 days away. That means one thing: Cracks are opening in Earth’s magnetic field.

The seasonal phenomenon is known as the “Russell-McPherron effect,” named after the researchers who first explained it more than 40 years ago.

These “equinox cracks” are causing geomagnetic activity and bright auroras around the Arctic Circle even without strong solar activity.

Visit today’s edition of Spaceweather.com for the full story.

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Video: CME’s and Solar Energetic Particles

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Many thanks to SWLing Post contributor, TomL, who writes:

Regarding the last couple of posts recently about what affects Space Weather (and HF radio communications), this talk last week from Solar scientist Joan Burkepile of the High Altitude Observatory discusses what causes Radiation storms from Coronal Mass Ejections. She makes it interesting from a physics point of view. And as we understand the sun better, we also learn more about how the rest of the universe behaves.

Click here to watch via YouTube.

Thanks for sharing this, Tom!

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Solar Minimum: A “relatively large” sunspot makes appearance

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(Image: spaceweather.com)

(Source: Southgate ARC)

With Solar Minimum right around the corner, sunspot counts are at an almost 10-year low. So it came as a surprise yesterday when a relatively large sunspot emerged near the sun’s eastern limb.

AR2699 has a primary dark core larger than Earth with many smaller magnetic condensations trailing behind it, in all stretching more than 75,000 km across the sun’s surface.

Rare “solar minimum sunspots” are capable of intense explosions just like sunspots during more active phases of the solar cycle.

Visit Spaceweather.com for more information and updates.

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