SOLAR SECTOR BOUNDARY CROSSING: NOAA forecasters say Earth is about to cross a fold in the heliospheric current sheet, a vast wavy structure in interplanetary space separating regions of opposite magnetic polarity. The crossing could trigger minor geomagnetic activity around Earth's poles during the late hours of April 30th. Free: Aurora Alerts
SOLAR TORNADO: A tornado of magnetized plasma is dancing along the sun's northeastern limb today. To see the twister in action, play this movie from NASA's Solar Dynamics Observatory and keep an eye on the circled plume:
Solar tornadoes are not uncommon, although they are often overlooked. This one is visible because it is jutting above the edge of the sun in profile, easy to see against the black space behind it. If a solar tornado over-rotates, magnetic fields inside the seething vortex can criss, cross, and explode, producing a type of solar flare that requires no sunspot. Will this one erupt? Stay tuned.
Realtime Space Weather Photo Gallery
THESE PENDANTS HAVE TOUCHED SPACE: These pendants have touched space--and returned to Earth in time for Mother's Day. To support their cosmic ray monitoring program, the students of Earth to Sky Calculus flew a payload-full of jewelry to the stratosphere onboard a high-altitude helium balloon. Here's one of the pendants 113,200 feet above the Sierras of central California:
These necklaces make great Mother's Day gifts--and you have have one for $89.95. Each glittering pendant comes with a greeting card showing the jewelry in flight and telling the story of its journey to the stratosphere and back again.
More far-out Mother's Day gifts may be found in the Earth to Sky Store. All proceeds support atmospheric radiation monitoring and hands-on STEM education.
Realtime Space Weather Photo Gallery
RARE BLUE AURORAS: Northern Lights are usually green, and sometimes red. Those are the colors produced by oxygen when it is excited by electrons raining down from space. On April 22nd, Didier Lindsey of Fox, Alaska, witnessed an apparition of aurora-blue:
Hours before he took the picture, a CME struck Earth's magnetic field, igniting a G2-class geomagnetic storm. "The sky filled with very active auroras," Lindsey says,"including these rare blues."
In auroras, blue is a sign of nitrogen. Energetic particles striking ionized molecular nitrogen (N2+) at very high altitudes produces a cold azure glow of the type captured in Lindsey's photo. Why it rivaled the usual hues of oxygen on April 22nd is unknown. Auroras still have the capacity to surprise.
Any auroras tonight, blue or otherwise, would be a surprise. Geomagnetic conditions are quiet as the solar wind relaxes into a steady breeze of low-speed plasma. NOAA forecasters estimate a scant 10% chance of polar geomagnetic storms on April 29th.