Hang the Transit of Venus on your wall! Hubble-quality images from NASA's Solar Dynamics Observatory are now available as metallic posters in the Space Weather Store.
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VOYAGER 1 AT THE FINAL FRONTIER: At the edge of the solar system, Voyager 1 is reporting a sharp increase in cosmic rays that could herald the spacecraft's long-awaited breakthrough into interstellar space. [video] [full story]
NEARLY-BLANK SUN: The departure of active sunspot AR1504 has left the Earth-facing side of the sun quiet and nearly blank. Only one small emerging sunspot interrupts the empty expanse photographed this morning by NASA's Solar Dynamics Observatory:
With no significant active regions facing Earth, NOAA forecasters estimate a mere 1% chance of strong M- or X-class solar flares. Solar activity should remain low for at least the next 24 hours. Solar flare alerts: text, voice.
Realtime Space Weather Photo Gallery
GREEN FLASH, BLUE FLASH: Green flashes at sunset are rare. Indeed, they were once thought mythological. Blue flashes are rarer still. On June 21st Göran Strand of Frösön, Sweden, saw them both in a single sunset:
"Tonight the weather was incredibly clear and fine, so I went out to photograph the sunset--and this was the result," says Strand. "The time interval between the first and last frames is 1 minute and 14 seconds."
Green flashes are formed when the prismatic action of the atmosphere splits the setting sun into basic R-G-B colors. Temperature inversions create a mirage, magnifying the green into an eye-catching flash.
Blues flashes are formed in the same way, but they are generally harder to see than green flashes, because blue flashes blend into the surrounding blue sky. When the air is exceptionally clear, however, the blue flash emerges.
For more rare sights occuring right now, browse the new Realtime Space Weather Photo Gallery.
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 June 22, 2012 there were 1317 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 |