SOLAR SECTOR BOUNDRY CROSSING: Last night, skies over Finland turned shocking green. What happened? Earth crossed through a fold in the heliospheric current sheet--a vast wavy structure that separates regions of positive and negative magnetic polarity in interplanetary space. This is called a "solar sector boundary crossing"; such crossings can cause geomagnetic disturbances around the poles. Aurora alerts: SMS Text.
A MUSICAL NOTE FROM THE MAGNETOSPHERE: High above the Arctic Circle in Lofoten, Norway, citizen scientist Rob Stammes operates a space weather monitoring station. His sensors detect ground currents, auroras, radio bursts, and disturbances in Earth's magnetic field. Yesterday, he says, "I received a musical note from the magnetosphere."
"Around 05.30 UTC on Jan. 18th, our local magnetic field began to swing back and forth in a rhythmic pattern," he says. "Electrical currents in the ground did the same thing. It was a nearly pure sine wave--like a low frequency musical note. The episode lastesd for more than 2 hours."
Stammes has received such notes before, but they are rare. "I see a pattern like this only about once a year," he says.
Space physicists call this phenomenon a "pulsation continuous" or "Pc" for short. Imagine blowing across a piece of paper, making it flutter with your breath. Solar wind does the same thing to magnetic fields. Pc waves are essentially flutters propagating down the flanks of Earth's magnetosphere excited by the breath of the sun.
Above: a magnetometer in Abisko, Sweden, recorded the same waves.
Yesterday's set of waves washed over Norway and Sweden, but almost nowhere else, according to the global INTERMAGNET network of magnetometers. It was a strictly regional phenomenon.
What happens in the sky when such a pure tone emerges from the natural background cacophony of magnetic activity? "I wish I knew," says Stammes. "I was asleep at the time." In fact, it's possible that no one knows. Tones like these are rare, and they all too often occur while skies are cloudy or daylit, blocking any peculiar auroras from view. Stammes says he plans to build an alert system to help him find out. No pun intended: Stay tuned.
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LOVE BIRDS IN THE STRATOSPHERE: Valentine's Day is coming. To get ready for the most romantic day of the year, the students of Earth to Sky Calculus launched a pair of crystal love birds to the stratosphere on Jan. 1, 2021. Here they are floating on a cosmic ray balloon 102,690 feet above the Sierra Nevada mountains of central California:
You can have them for $129.95. The students are selling love birds to fund their cosmic ray ballooning program. Made of high-quality Borosilicate Crown Crystal often used in lenses and prisms, the birds glitter colorfully in sunlight, even at the edge of space. Each purchase comes with a greeting card showing the birds in flight and telling the story of their journey to the stratosphere and back again.
Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education
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