Listen to radar echoes from satellites and meteors, live on listener-supported Space Weather Radio.
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EDGE OF SPACE CHRISTMAS CARDS: What do you give to the sky watcher who has everything? How about a Christmas card from the Edge of Space? For only $49.95, the students of Earth to Sky Calculus will fly your holiday greeting or favorite picture to the top of Earth's atmosphere, photograph it, and return the snapshot in time for the holidays. It's a unique gift! The group has previously flown cupcakes, shoes, US presidents, ad banners and telescopes. This holiday magic is performed using suborbital helium balloons. Contact Dr. Tony Phillips for more information.
GEMINID METEOR SHOWER--IT'S UNDERWAY: Last night, NASA's network of all-sky meteor cameras reported 23 Geminid fireballs over the United States. This sharp uptick in activity signals the official beginning of the 2013 Geminid meteor shower. For the next 3 to 4 days, Earth will pass through a stream of debris from rock comet 3200 Phaethon, producing dozens of meteors per hour flying out of the contellation Gemini. "There is a nice show going on right now," says Bill Cooke, head of NASA's Meteoroid Environment Office.
The multiple cameras of NASA's fireball network are able to measure the orbits of Geminid meteoroids. This plot shows the orbits of the 39 fireballs recorded so far this week:
Earth is the blue dot where all the orbits intersect. The purple curve shows the path of Geminid parent 3200 Phaethon.
Forecasters expect the shower to peak on Dec. 13-14 when Earth passes through the busiest part of Phaethon's debris stream. Peak rates could reach 120 meteors per hour. However, glare from the nearly-full Moon could reduce the number of visible meteors 2- to 3-fold. Cooke advises looking during the hours just before local sunrise on Saturday, Dec. 14th. "At that time, the Moon will be below the horizon, improving your chances of seeing the show."
You can listen to radar echoes from the Geminids, unaffected by moonlight, on Space Weather Radio. Also, tune into NASA's live web chat about the Geminids on Friday the 13th beginning at 11 pm EST.
Realtime Meteor Photo Gallery
CORONAL HOLE: NASA's Solar Dynamics Observatory is monitoring a large coronal hole in the sun's northern hemisphere. Shown here in an extreme ultraviolet photo taken Dec. 11th, the UV-dark chasm overlies more than 500 billion square kilometers of solar terrain:
Coronal holes are places in the sun's atmosphere where the magnetic field opens up and allows solar wind to escape. A broad stream of solar wind flowing from this particular coronal hole should reach Earth on Dec. 15-17.
The last time a solar wind stream blew past Earth, on Dec. 7th, the impact sparked Northern Lights in the United States as far south as Montana and Michigan. A repeat performance could be in the offing. High-latitude sky watchers should be alert for auroras early next week. Aurora alerts: text, voice
Realtime Aurora Photo Gallery
ELECTRIC-BLUE CLOUDS OVER ANTARCTICA: The season for noctilucent clouds has begun in the southern hemisphere. NASA's AIM spacecraft is monitoring a vast bank of rippling electric-blue NLCs blanketing almost all of Antarctica. This two week movie chronicles the onset of the clouds in late November and their rapid spread into December:
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 summer because that is when water molecules are wafted up from the lower atmosphere to mix with the meteor smoke. That is also, ironically, the time when the upper atmosphere is coldest, allowing the ice crystals of NLCs to form.
In recent years NLCs have intensified. Some researchers believe this is a sign of climate change. One of the greenhouse gases that has become more abundant in Earth's atmosphere since the 19th century is methane. "When methane makes its way into the upper atmosphere, it is oxidized by a complex series of reactions to form water vapor," explains Hampton University Professor James Russell, the principal investigator of AIM."This extra water vapor is then available to grow ice crystals for NLCs."
Realtime Space Weather Photo Gallery
Comet ISON 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 Dec. 12, 2013, the network reported 54 fireballs.
(26 sporadics, 23 Geminids, 3 December Monocerotids, 1 alpha Canis Majorid, 1 sigma Hydrid)
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 December 12, 2013 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.
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| ||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 |
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