ANOTHER BIG SUNSPOT APPEARS: With one big sunspot (AR2740) already turning toward Earth, another big sunspot (AR2741) is now emerging over the sun's eastern limb. Amateur astronomers with safe solar telescopes are encouraged to point their filtered optics here and monitor developments. Instant Aurora Alerts: SMS Text.
ACTIVE SUNSPOT: Big sunspot AR2740 is turning toward Earth and crackling with solar flares. The most intense so far registered M1 on the Richter Scale of Solar Flares. NASA's Solar Dynamics Observatory recorded the extreme ultraviolet flash on May 6th:
Radiation from the flare briefly ionized the top of our planet's atmosphere, producing a brownout of shortwave radio signals over Asia and the Indian Ocean: map. Frequencies affected were mainly below 20 MHz. Ships at sea and ham radio operators may have noticed the disturbance on Monday, May 6th, around 05:10 UT.
This sunspot is a big one (especially considering that we are in a deep solar minimum). It is twice as wide as Earth, making it an easy target for backyard solar telescopes. Shahrin Ahmad of Kuala Lumpur, Malaysia, took this picture on May 5th:
"I was able to see this big sunspot despite bad seeing (2/5)," says Ahmad. "It's incredible for this sunspot to have survived so long!"
Indeed, this is the second time AR2740 has circled the sun. We saw it for the first time in April when it strafed Earth with loud shortwave radio bursts. Now it's back, still big and intact, following a 2-week trip around the farside of the sun.
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A GREEN FLASH IN THE CLOUDS: For seaside photographers, nothing beats a green flash--that sudden pulse of verdant light at sunset as the sun vanishes beneath the ocean waves. Thom Peck of Poway CA was near the Pacific Ocean on May 4th when he captured a green flash. But it didn't come from the ocean waves. It came from the top of a cloud:
This is a rare 'cloud-top' green flash, sometimes seen as the sun's rays graze a distant cloud bank. They are not well understood. Ordinary green flashes require a temperature inversion layer near the sea surface. Similar inversions may sometimes occur at the top of marine stratus clouds.
"The green flash was not naked eye--or at least we didn't see it," says Peck. "But we photographed it easily enough using my Canon T6i digital camera." Photo settings may be found here.
Realtime Space Weather Photo Gallery
MOTHER'S DAY IS LESS THAN 1 WEEK AWAY: 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!
Far Out Gifts: Earth to Sky Store
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