When is the best time to see auroras? Where is the best place to go? And how do you photograph them? These questions and more are answered in a new book, Northern Lights - a Guide, by Pal Brekke & Fredrik Broms.
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CHANCE OF FLARES: NOAA forecasters estimate a 40% chance of M-class flares and a 5% chance of X-flares on Aug. 28th. The likely source is sunspot AR2146, which has a 'beta-gamma-delta' magnetic field that harbors energy for strong eruptions. The geoeffectiveness of any flares from this region will be mitigated, however, by its off-center location on the solar disk. Solar flare alerts: text, voice
GEOMAGNETIC ACTIVITY: Earth's magnetic field is still reverberating from a pair of CME strikes on August 27th. Although neither impact was particularly strong, the internal magnetic structure of the two solar storm clouds was just right for auroras. Last night, Alan Dyer photographed the display over the Grasslands National Park in Saskatchewan, Canada. Click to view a complete panorama:
"I shot this at the old pioneer Larson Ranch site in the Frenchman River valley just as the magnetic storm of Aug 27/28 hit its peak, covering much of the northern sky and lighting the ground and ranch buildings green," says Dyer. "The Larsons ran their ranch from the 1920s until 1985 when theirs became first land to be bought for the new Grasslands National Park. This is a stitch of 8 segments, each shot with the 15mm full-frame fish-eye lens at f/3.2 and Canon 6D at ISO 2500 for 1 minute each."
The CMEs that instigated the display were launched toward Earth on Aug. 22nd. As NOAA analysts predicted, the solar wind speed did not change much when the slow-moving CMEs arrived. However, the storm clouds were still effective because they contained a south-pointing magnetic field that opened a crack in Earth's magnetosphere. Solar wind poured in to fuel the show.
High-latitude sky watchers, if it is dark where you live, remain alert for auroras. Solar wind conditions continue to favor geomagnetic activity as August 28th unfolds. Aurora alerts: text, voice
Realtime Aurora Photo Gallery
TWILIGHT TRIANGLE: Go outside just after sunset and look southwest. Something there will make you do a double-take. Mars and Saturn have converged alongside the second brightest star in Libra to form a pretty twilight triangle:
"It was an amazing triangle," says photographer Marek Nikodem of Szubin, Poland. The planets are labeled in Nikodem's photo, but that star is not. That's because its name wouldn't fit. The second brightest star in Libra is Zubenelgenubi. Pronounced "zoo-BEN-el-je-NEW-bee," it is a double star 77 light years from Earth easily split by binoculars or a small backyard telescope.
Soon, the threesome will become a foursome. The crescent Moon will pass through the triangle on August 30th and 31st. On those evenings, in the time it takes to scan your telescope around a small patch of sky, you can see a double star, the rings of Saturn, the red disk of Mars, and the cratered landscape of the Moon. Mark your calendar!
Realtime Space Weather Photo Gallery
Realtime Meteor Photo Gallery
Realtime NLC 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 Aug. 28, 2014, the network reported 27 fireballs.
(25 sporadics, 2 Southern delta Aquariids)
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 August 28, 2014 there were 1495 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 |