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GEMINID METEOR SHOWER: Mark your calendar: The annual Geminid meteor shower peaks this year on Dec. 14th when dark-sky observers around the world could see as many as 120 meteors per hour. The source of the display is "rock comet" 3200 Phaethon. As November comes to a close, Earth is entering the outskirts of 3200 Phaethon's debris stream, and this is causing some Geminids to appear weeks ahead of peak night. The first Geminid fireball of the season was detected on Nov. 26th by NASA's network of all-sky meteor cameras. Meteor alerts: text, voice
ELECTRIC-BLUE CLOUDS APPEAR OVER ANTARCTICA: NASA's AIM spacecraft has detected electric-blue clouds forming over Antarctica. These are noctilucent clouds (NLCs), and their apparition marks the beginning of the 2014-2015 season for NLCs in the southern hemisphere.
NLCs are Earth's highest clouds. Seeded by meteor smoke, they form at the edge of space 83 km above Earth's surface. When sunlight hits the tiny ice crystals that make up these clouds, they glow electric blue.
NLCs appear during late spring and summer because that is when the upper atmosphere is ironically coldest, allowing the ice crystals of NLCs to form. Northerners reading this story should remember that it is late spring in Antarctica, so the noctilucent clouds are appearing right on time.
Previous results from AIM have shown that NLCs are like a great "geophysical light bulb." They turn on very year in late spring, reaching almost full intensity over a period of no more than 10 days. At the moment, only a few puffs and wisps of NLCs are visible over Antarctica. By Dec. 10th, the whole continent could be blanketed in electric blue as the bulb begins to glow in earnest. Stay tuned!
Realtime NLC Photo Gallery
SPACE WEATHER BALLOON EXPLODES: On Nov. 23rd, the students of Earth to Sky Calculus launched a Space Weather Buoy to the stratosphere. Carried aloft by a suborbital helium balloon, the payload contained a pair of X-ray/gamma-ray sensors to measure cosmic radiation levels inside Earth's ozone layer. About 90 minutes after launch, this is what happened:
The balloon exploded: #1, #2, #3, #4.
It's supposed to do that. As a weather balloon ascends, it expands into the rapidly thinning air high above Earth. The diameter multiplies until the growing sphere is as wide as a small house. Eventually, the rubber fabric of the balloon reaches its elastic limit, and it ruptures. If it didn't, we would never get the payload back!
This balloon exploded at an altitude of 102,986 feet. The almost-silent blast was captured by a camera looking up from the payload below. Next, a parachute opened and the payload descended to Earth, landing in a remote corner of Death Valley where an Earth to Sky recovery team retrieved it yesterday.
The students and their mentor Dr. Tony Phillips of spaceweather.com are examining the radiation data now. This is the first time they have flown two radiation sensors. Cross-calibrating the two sensors in a single flight will allow the team to fly them separately on future missions, launching multiple balloons in rapid succession to investigate the dynamics of solar storms. Solar flare alerts: text, voice
Realtime Space Weather Photo Gallery
Realtime Aurora Photo Gallery
Realtime Comet 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. 29, 2014, the network reported 29 fireballs.
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 29, 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 |