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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PERSEID METEOR SHOWER: Meteor activity is increasing as Earth plunges deeper into the debris stream of Comet Swift-Tuttle, source of the annual Perseid meteor shower. On the nights of Aug 4-5, NASA cameras recorded 26 Perseid fireballs over the USA. Counts are high even though the shower's peak is still more than a week away. To see for yourself, get away from city lights and look up during the dark hours before sunrise. You can also hear the Perseids on Space Weather Radio.
ROCKET LAUNCH PRODUCES NOCTILUCENT CLOUDS: This morning, August 5th, a SpaceX Falcon 9 rocket lifted off from Cape Canaveral carrying the AsiaSat 8 telecommunications satellite. About an hour and a half after the 4 AM launch, electric-blue clouds appeared over Orlando FL:
"These clouds appeared just before sunrise," says photographer Mike Bartils.
These are, essentially, man-made noctilucent clouds (NLCs). Water vapor in the exhaust of the rocket crystallized in the high atmosphere, creating an icy cloud that turned blue when it was hit by the rays of the morning sun. Years ago, space shuttle launches produced similar displays.
Natural NLCs form around Earth's poles when water vapor in the mesosphere crystalizes around meteor smoke. Sometimes they spread as far south as Colorado and Utah, but rarely or never Florida. Electric-blue over the Sunshine State requires a rocket launch, and that's what happened today. Browse the realtime photo gallery for more images of the Falcon 9 launch:
Realtime Space Weather Photo Gallery
FIREBALL EXPLODES, SPRAYS COUNTRYSIDE: On Saturday night, August 2nd, NASA meteor cameras detected a fireball that exploded in a flash of light many times brighter than the Moon. It came not from the Perseid debris stream, but rather from the vicinity of the asteroid belt between Mars and Jupiter. Watch the movie, then read on for more information:
"The meteoroid was about 15 inches in diameter and weighed close to 100 lbs," says Bill Cooke of NASA's Meteoroid Environment Office. "Travelling 47,000 miles per hour, it broke apart in a brilliant flash of light above the Alabama town of Henagar. Our cameras continued to track a large fragment until it disappeared 18 miles above Gaylesville, located near Lake Weiss close to the Georgia state line. At last sight, the fragment was still traveling at 11,000 miles per hour. Based on the meteor's speed, final altitude, and weak doppler radar signatures, we believe that this fireball produced small meteorites on the ground somewhere between Borden Springs, AL and Lake Weiss."
The NASA Meteoroid Environment Office would like to hear from those in the area around Alabama's Lake Weiss who may have heard sonic booms or similar sounds around 10:20 PM Saturday night. Please contact Dr. Bill Cooke at email@example.com with reports.
Realtime Meteor Photo Gallery
SPONSOR A SPACE WEATHER BALLOON: This Friday, 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 their research is to discover how solar activity affects the ozone layer and alters levels of radiation at altitudes of interest to space tourism. They are also launching microbes to find out which species can survive in space-like conditions. Readers who wish to support this exciting student-led work can sponsor the flight with an ad or message to be launched with the payload and displayed as shown:
For $500 the students will fly your message to the edge of space and return it to you along with complete video of the flight. Also, selected still shots will be displayed on spaceweather.com as part of our coverage of the event. Interested? Please email Dr. Tony Phillips for more information.
Realtime Space Weather Photo Gallery
AURORA SEASON BEGINS IN ALASKA: As northern summer comes to an end and the midnight sun sets, auroras are returning to the darkening skies of Alaska. From outside Fairbanks, James McClean sends this report: "Whoooo Hoooo!!!! I spotted the first auroras of the season over Chena Hot Springs." He took this picture on August 4th:
"The aurora was only a thin whisper of green lasting only a few seconds in a sky full of twilight blue and some noctilucent clouds," says McClean. "Let's hope this is the kickoff to another great season of aurora hunting at Chena Hot Springs Resort."
The display was caused by a minor stream of solar wind that buffeted Earth's magnetic on August 4th. Ironically, the Northern Lights were even easier to see farther south where skies were darker. Aurora reports have also been received from Michigan, Minnesota, and Alberta. NOAA forecasters estimate a 25% chance of more geomagnetic activity tonight as the solar wind continues to blow. Aurora alerts: text, voice
Realtime Aurora Photo Gallery
Realtime Comet 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. 5, 2014, the network reported 39 fireballs.
(22 sporadics, 13 Perseids, 2 alpha Capricornids, 1 Northern delta Aquariid, 1 Southern delta Aquariid)
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 5, 2014 there were 1498 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 |