CME GLANCING-BLOW POSSIBLE ON MAY 7th: The sun is crackling with solar flares, and these explosions are hurling multiple overlapping CMEs into space. NOAA forecasters say that one of them might graze Earth's magnetosphere on May 7th. This is a low confidence forecast. So many CMEs are leaving the sun, it is difficult to unravel their distinct shapes and trajectories. If a CME does strike on May 7th, it should spark no more than minor G1-class geomagnetic storms. Aurora alerts: SMS Text
ANOTHER SUNSPOT IS APPROACHING: A new and potentially active sunspot group is hiding just behind the sun's southeastern limb. NASA's Solar Dynamics Observatory photographed plumes of debris thrown up by a partially eclipsed solar flare on May 5th:
The source of the explosion will reveal itself this weekend when it rotates over the sun's horizon, turning toward Earth. Stay tuned. Solar flare alerts: SMS Text
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'COMET' MERCURY: On May 1st, Mercury's comet-like tail reached its maximum brightness for this orbit around the sun. Dr. Sebastian Voltmer photographed it from La Palma in the Canary Islands:
"You can even see some very small features in the tail, which is more than 24 million kilometers long," says Voltmer.
What made the tail so bright on May 1st? Research shows that Mercury's tail is brightest when the planet is ±16 days from perihelion (closest approach to the sun). May 1st was the 16th day after perihelion.
That doesn't really answer the question, though. Here's the rest of the story: Mercury's tail is rich in sodium, an element sputtered off the planet's surface by solar wind and micrometeoroid impacts. Sodium scatters yellow light from the sun. Ironically, the sun has a deficit of light at the precise yellow wavelength sodium scatters best. Take a look at the sun's spectrum and note the dark sodium absorption lines (Fraunhofer lines). Mercury's tail only "lights up" when those dark lines are fully Doppler-shifted away. This happens when Mercury is ±16 days from perihelion: movie.
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MOTHER'S DAY IS MAY 8TH: Are you looking for an out-of-this world Mother's Day gift? Consider this: Every time the students of Earth to Sky Calculus launch a cosmic ray balloon, they include something extra in the payload--something Mom will love:
Every item in the Earth to Sky Store has flown to the edge of space and comes with a greeting card showing the item in flight. The interior of the card tells the story of the gift's journey from launch to landing. Mom-satisfaction guaranteed!
Mother's Day Special: Use coupon code "SPACEMOM" at checkout for a 10% discount. Offer valid from now until Mother's Day (May 8, 2022) .
Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education
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