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CME IMPACT EXPECTED: A CME so weak that it barely stands out from the ambient solar wind is expected to hit Earth's magnetic field today. Mindful that even weak CMEs can be potent, NOAA forecasters put the odds of a polar geomagnetic storm at 40%. Arctic sky watchers should be alert for auroras on Nov. 20-21. Aurora alerts: text, voice
BEAR CLAW SUNSPOT: Imagine a bear claw with toes the size of Earth. Yesterday, Philippe Tosi of Nîmes, France, looked through the eyepiece of his solar telescope and saw exactly that:
This is old sunspot AR2192, now making its second pass across the face of the sun. "I created this high resolution picture by combining six images," says Tosi. Click to view the full panorama.
Magnetic fields criss-crossing the toes and pad of this Ursidamorphic structure harbor energy for M- and X-class solar flares. However, the sunspot has been quiet for almost three days, so NOAA forecasters are estimating a relatively low 5% chance of X-flares on Nov. 20th. Solar flare alerts: text, voice
Realtime Space Weather Photo Gallery
LEONID FIREBALLS: This week, Earth passed through a stream of debris from Comet 55P/Tempel-Tuttle, source of the annual Leonid meteor shower. Forecasters expected the display to be meagre, in part because it has been 15 years since the comet visited the inner solar system. Contrary to expectations, however, the Leonids of 2014 have produced a pleasing number of fireballs.Bill Cooke, who runs NASA's all-sky network of meteor cameras reports: "We have 67 confirmed Leonids so far, despite a couple of days of bad weather." Cooke has plotted the orbit of each fireball to create this summary:
The blue curves show the orbits of all the Leonid fireballs that disintegrated above the USA in view of network cameras between Nov. 15th and 20th. Those curves are a good match to the orbit of Comet Tempel-Tuttle, color-coded purple. "That's how we know they are Leonids," explains Cooke.
Last night alone, the network picked up 15 more fireballs, which means the shower might not yet be finished. Readers who wake up before sunrise, and who are not blanketed by snow clouds, should remain alert for bright meteors. ( And if you do have snow clouds, listen for Leonid echoes on Spaceweather.com's live meteor radar, which operates even during winter storms.)
Realtime Meteor Photo Gallery
Realtime Comet Photo Gallery
Realtime Aurora 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 Nov. 20, 2014, the network reported 44 fireballs.
(26 sporadics, 15 Leonids, 2 Northern Taurids, 1 alpha Monocerotid)
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 November 20, 2014 there were 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 |