On October 23rd there will be a partial eclipse of the Sun. Got clouds? No problem. The event will be broadcast live on the web by the Coca-Cola Science Center. | | | PARTIAL SOLAR ECLIPSE: This Thursday Oct. 23rd, the Moon will pass in front of the sun, off center, producing a partial solar eclipse visible from almost all of North America. Get the full story from Science@NASA. MONSTER SUNSPOT: The biggest sunspot of the current solar cycle is turning toward Earth. This morning when astronomer Karzaman Ahmad of Malaysia's Langkawi Nagtional Observatory looked through the eyepiece of his solar telescope, he declared AR2192 a "monster" and snapped this picture: This behemoth active region is 125,000 km wide, almost as big as the planet Jupiter. These dimensions make it an easy target for backyard solar telescopes--hence so many pictures in the realtime photo gallery. A few days ago, AR2192 unleashed an X1-class solar flare. Since then the sunspot has almost doubled in size and developed an increasingly unstable 'beta-gamma-delta' magnetic field. It would seem to be just a matter of time before another strong explosion occurs. NOAA forecasters estimate at 60% chance of M-class flares and a 20% chance of X-flares on Oct. 21st. Solar flare alerts: text, voice Realtime Space Weather Photo Gallery SOLAR WIND SPARKS NORTHERN LIGHTS: A high-speed stream of solar wind is buffeting Earth's magnetic field, sparking bright lights around both poles. "This evening the auroras appeared everywhere," reports Anne Birgitte Fyhn, who photographed the display from a pond on Kvaløya island, Tromsø, Norway: "They were amazing," she says. "I ran around the pond a couple of times taking pictures from different spots. Finally, I decided to just sit down, look up, and enjoy the show." High-latitude sky watchers should remain alert for auroras on Oct. 21-22. NOAA forecasters estmate a 45% chance of geomagnetic storms as the solar wind continues to blow. Aurora alerts: text, voice Realtime Aurora Photo Gallery Realtime Comet Photo Gallery Realtime Eclipse Photo Gallery Every night, a network of NASA all-sky cameras scans the skies above the United States for meteoritic fireballs. Automated software maintained by NASA's Meteoroid Environment Office calculates their orbits, velocity, penetration depth in Earth's atmosphere and many other characteristics. Daily results are presented here on Spaceweather.com. On Oct. 21, 2014, the network reported 56 fireballs. (33 sporadics, 21 Orionids, 1 epsilon Geminid, 1 Leonis Minorid) In this diagram of the inner solar system, all of the fireball orbits intersect at a single point--Earth. The orbits are color-coded by velocity, from slow (red) to fast (blue). [Larger image] [movies] Potentially Hazardous Asteroids ( PHAs) are space rocks larger than approximately 100m that can come closer to Earth than 0.05 AU. None of the known PHAs is on a collision course with our planet, although astronomers are finding new ones all the time. On October 21, 2014 there were 1508 potentially hazardous asteroids. Notes: LD means "Lunar Distance." 1 LD = 384,401 km, the distance between Earth and the Moon. 1 LD also equals 0.00256 AU. MAG is the visual magnitude of the asteroid on the date of closest approach. | The official U.S. government space weather bureau | | The first place to look for information about sundogs, pillars, rainbows and related phenomena. | | Researchers call it a "Hubble for the sun." SDO is the most advanced solar observatory ever. | | 3D views of the sun from NASA's Solar and Terrestrial Relations Observatory | | Realtime and archival images of the Sun from SOHO. | | from the NOAA Space Environment Center | | the underlying science of space weather | |