Marianne's Heaven On Earth Aurora Chaser Tours Chasethelighttours.co.uk invites you to join them in their quest to find and photograph the Aurora Borealis. Experience the winter wonderland in the Tromsø Area. | | | CHRISTMAS FULL MOON: Santa can turn off his headlamp. Why? Because the Moon will be full on Christmas. The last time the full Moon fell on Dec. 25th was 1977, and it won't happen again until 2034. That makes the Christmas Full Moon of 2015 a rare event. Enjoy the holiday moonlight. [photo gallery] SOLAR FLARE AND RADIO BLACKOUT: In the past 24 hours, sunspot AR2473 has more than quadrupled in size. On Dec. 23rd (00:40 UT) it erupted, producing an M4-class solar flare. NASA's Solar Dynamics Observatory recorded the extreme ultraviolet flash: UV radiation from the flare bathed the top of Earth's atmosphere, ionizing atoms and molecules, and altering the normal propagation of radio transmissions. Around the South Pacific Ocean, where the sun was high in the sky, a full-fledged shortwave radio blackout occured. This map from NOAA shows the affected area: The type of people who would notice such a blackout are ham radio operators, mariners, and some aviators who use shortwave radio in their work. The event lasted approximately half an hour. More flares and blackouts are possible in the days ahead as AR2374 turns toward Earth. NOAA forecasters estimate a 45% chance of M-class explosions on Dec. 23-24. Solar flare alerts: text or voice Realtime Spaceweather Photo Gallery LAST-MINUTE, OUT-OF-THIS-WORLD CHRISTMAS GIFT: Is there a young scientist in your life? For Christmas, you can give them the gift of exploration--specifically, a trip to the edge of space: To raise funds for its student research program, Earth to Sky Calculus is selling a limited number of Holiday Season balloon flights carrying ... whatever you desire. Small experiments. Holiday or anniversary photos. Business advertisements. The sky is the limit. Young people receiving this gift can design their own experiment and attend the launch via Skype. The gift includes a brainstorming session via Skype with Dr. Tony Phillips and the students of Earth to Sky. Cost: $500. Buy now and receive the certificate by email in time for Christmas. Contact Dr. Tony Phillips to book your flight. SOLSTICE AURORAS: Winter nights are supposed to be long and dark. This week they have only been long. Auroras around the Arctic Circle have wiped out the darkness with displays like this: "It was a beautiful evening in the Yukon," says Joseph Bradley, who took the picture on Dec. 20th. "The lights came out early and--WOW--what an amazing show. It had me running all over the place. Fellow photographer Jono and I had a great 4 hour run!!" The lights Bradley saw were ignited by a CME strike on Saturday, Dec. 19th. The impact caused intermittant G1 and G2-class geomagnetic storms for nearly two days. Those storms are subsiding now, possibly opening a window into winter darkness. NOAA says the chance of polar geomagnetic storms on Dec. 23rd is no more than 20%. Aurora alerts: text or voice Realtime Aurora Photo Gallery Realtime Meteor 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. 23, 2015, the network reported 19 fireballs. (15 sporadics, 4 December Leonis Minorids) 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 23, 2015 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. | Cosmic Rays in the Atmosphere | Situation Report -- Oct. 30, 2015 | Stratospheric Radiation (+37o N) | Cosmic ray levels are elevated (+6.1% above the Space Age median). The trend is flat. Cosmic ray levels have increased +0% in the past month. | Sept. 06: 4.14 uSv/hr (414 uRad/hr) | Sept. 12: 4.09 uSv/hr (409 uRad/hr) | Sept. 23: 4.12 uSv/hr (412 uRad/hr) | Sept. 25: 4.16 uSv/hr (416 uRad/hr) | Sept. 27: 4.13 uSv/hr (413 uRad/hr) | Oct. 11: 4.02 uSv/hr (402 uRad/hr) | Oct. 22: 4.11 uSv/hr (411 uRad/hr) | These measurements are based on regular space weather balloon flights: learn more. Approximately once a week, Spaceweather.com and the students of Earth to Sky Calculus fly "space weather balloons" to the stratosphere over California. These balloons are equipped with radiation sensors that detect cosmic rays, a surprisingly "down to Earth" form of space weather. Cosmic rays can seed clouds, trigger lightning, and penetrate commercial airplanes. Our measurements show that someone flying back and forth across the continental USA, just once, can absorb as much ionizing radiation as 2 to 5 dental X-rays. Here is the data from our latest flight, Oct. 22nd: Radiation levels peak at the entrance to the stratosphere in a broad region called the "Pfotzer Maximum." This peak is named after physicist George Pfotzer who discovered it using balloons and Geiger tubes in the 1930s. Radiation levels there are more than 80x sea level. Note that the bottom of the Pfotzer Maximim is near 55,000 ft. This means that some high-flying aircraft are not far from the zone of maximum radiation. Indeed, according to the Oct 22th measurements, a plane flying at 45,000 feet is exposed to 2.79 uSv/hr. At that rate, a passenger would absorb about one dental X-ray's worth of radiation in about 5 hours. The radiation sensors onboard our helium balloons detect X-rays and gamma-rays in the energy range 10 keV to 20 MeV. These energies span the range of medical X-ray machines and airport security scanners. | 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 | | a sponsor of SpaceWeather.com | | Web-based high school science course with free enrollment | | the underlying science of space weather | |