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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SPACE WEATHER BALLOON LAUNCH: This Friday, Aug. 8th, the students of Earth to Sky Calculus will continue their ongoing campaign of high-altitude research with the launch of another Space Weather Radiation Buoy. The purpose of the research is to discover how solar activity affects the ozone layer and alters levels of radiation at altitudes of interest to aviation and space tourism. Stay tuned for launch photos @spaceweatherman.
PERSEID FIREBALLS: The full Moon of August 10th is no ordinary full Moon--it's a supermoon, the biggest and brightest of 2014. This has raised concerns that bright moonlight will outshine the Perseid meteor shower, underway now as Earth moves into the debris stream of parent Comet Swift-Tuttle. So far the Perseids are holding their own. In recent nights, observers have reported dozens of Perseid fireballs cutting through the glare. This one, photographed by Thomas Ashcraft in New Mexico, came with sound effects:
Play it again. The ghostly warbling sound you just heard was a terrestrial radio signal bouncing off the ionized trail of the fireball. This method of detecting meteors is called "forward scatter radar." Ashcraft, who is an amateur radio astronomer, routinely uses this method to monitor meteor activity over his observatory not far from Santa Fe. Lately, he has been recording lots of echoes.
"My radio fireball array and all-sky camera caught this Perseid earthgrazer at 11:30 pm here in New Mexico as the constellation Perseus was coming up over the northern horizon," says Ashcraft. "It caused a dynamic dopplering forward scatter reflection in stereo on two of my radios."
"Even though there is a bright moon at the moment, there will still be some beautiful Perseids over the next few nights," he predicts.
Got clouds? You can listen to more meteor echoes, live, on Space Weather Radio.
Realtime Meteor Photo Gallery
HISTORIC COMET RENDEZVOUS: For the first time ever, a spacecraft from Earth is traveling alongside a comet. Yesterday, at the end of a 10 year and 6 billion km journey, the European Space Agency's Rosetta probe reached 67P/Churyumov-Gerasimenko. On approach, Rosetta's OSIRIS camera took this stunning picture of the comet's nucleus only 130 km away:
The image clearly shows a range of features including boulders, craters and steep cliffs. As the ESA science team noted this morning, "choosing a landing site will not be easy." More close-up shots may be found here.
Rosetta has reached the comet, but it is not in orbit yet. As this video shows, the spacecraft will spend the next month maneuvering closer and closer to the comet's core. When Rosetta dscends to within about 30 km of the surface in early September, the comet's weak gravity will be able to capture the spacecraft into a final orbit.
A full replay of Rosetta's arrival at 67P is now available here: http://www.livestream.com/eurospaceagency
Realtime Comet Photo Gallery
Realtime Space Weather Photo Gallery
Realtime Aurora 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. 8, 2014, the network reported 83 fireballs.
(63 sporadics, 17 Perseids, 1 , 1 Southern delta Aquariid, 1 alpha Capricornid)
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 8, 2014 there were 1499 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 |