OMEGA SUNSET: “Last night’s sunset was an amazing sight,” reports Pete Lawrence from West Beach in Selsey, UK. “As the sun approached the horizon, the lower half of the solar disk extended downwards to touch an image of itself rising out of the waves.” He took this picture of the phenomenon:

Jules Verne famously likened this kind of sunset to an Etruscan Vase. Others call it an “Omega sunset” because it resembles the Greek letter. Either way, it is caused by warm air overlying the sea surface, which refracts the rays of the setting sun to produce a mirage, as shown.

This is a good weekend to watch the sunset. Not only are mirages a possibility, but also you might observe a sunspot in the twilight.

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Last night in Tromsø, Norway, the solar wind combined with moonlight and snow to produce a scene that had onlookers asking themselves,can it get any better than this? One of those onlookers was Thilo Bubek, and he took this picture:

“The whole evening was a perfect show with strong auroras in many colours,” says Bubek. “We were able to capture some fantastic images.”

But can it get any better? Maybe later today: A solar wind stream is due to hit Earth’s magnetic field on Jan. 14-15, possibly sparking even stronger displays

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An active region on the far side of the sun is crackling with solar flares and hurling CMEs into space. Click on the image to view the latest blast on Jan. 14th:

This eruption was nearly as dramatic as another one the day before, and suggests that more eruptions are in the offing.

The explosions are occuring almost directly beneath NASA’s STEREO-B spacecraft. STEREO’s onboard telescope has recorded bright flashes of extreme UV radiation and shadowy shock waves emanating from the blast site (Jan. 13th movie). The telescope has also pinpointed the source: It is located just over the sun’s eastern limb. Solar rotation is turning the region toward Earth, so geoeffective solar activity could commence within days.

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On Jan. 11th around 8:45 pm CST, many people in the southeastern USA saw something streak across the sky and explode. The blast produced infrasound waves detected as far away as Canada. Data from a University of Western Ontario monitoring station reveals the nature of the event: “It was a meter-size meteor with more than a metric ton of mass, exploding like 40 to 80 tons of TNT,” says Bill Cooke of NASA’s Meteoroid Environment Office. “This was one big rock, and the odds are good that there are fragments on the ground.” An analysis of sightings by meteorite hunter Rob Matson suggests the fall zone is in central Mississippi, possibly around Jackson. People in the area should be alert for odd-looking rocks.

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Jan. 12, 2011: The sun has just experienced a storm—not of explosive flares and hot plasma, but of icy comets.

“The storm began on Dec 13th and ended on the 22nd,” says Karl Battams of the Naval Research Lab in Washington, DC. “During that time, the Solar and Heliospheric Observatory (SOHO) detected 25 comets diving into the sun. It was crazy!”

Sundiving comets—a.k.a. “sungrazers”—are nothing new. SOHO typically sees one every few days, plunging inward and disintegrating as solar heat sublimes its volatile ices. “But 25 comets in just ten days, that’s unprecedented,” says Battams.

“The comets were 10-meter class objects, about the size of a room or a house,” notes Matthew Knight of the Lowell Observatory in Flagstaff, Arizona. “As comets go, these are considered small.”

SOHO excels at this kind of work. The spacecraft’s coronagraph uses an opaque disk to block the glare of the sun like an artificial eclipse, revealing faint objects that no Earth-bound telescope could possibly see. Every day, amateur astronomers from around the world scrutinize the images in search of new comets. Since SOHO was launched in 1996, more than 2000 comets have been found in this way, an all-time record for any astronomer or space mission.

Battams and Knight think the comet-storm of Dec. 2010 might herald a much bigger sungrazer to come, something people could see with the naked eye, perhaps even during the day.

“It’s just a matter of time,” says Battams. “We know there are some big ones out there.”