Directly under the Arctic Circle! Marianne's Arctic Xpress in Tromsø offers fjord, whale and wildlife tours by day, aurora tours by night. Book Now and get a 10% discount on combo day and night adventures. | | | EUROPEAN SPACECRAFT SET TO CRASH INTO COMET: On Sept. 30th, Europe's Rosetta spacecraft will deliberately crash land on Comet 67P/Churyumov–Gerasimenko, ending the probe's two year mission in orbit around the comet's nucleus. With cameras and other instruments taking data until the last moment, Rosetta will descend into a mysterious region known as Ma'at home to several "active pits," which are spewing jets of gas and dust into space. Rosetta's death plunge could be exciting, indeed. Monitor ESA's Rosetta blog for updates. 'A-BOMB' SPRITE OVER THE CARIBBEAN: Yesterday, Frankie Lucena of Cabo Rojo, Puerto Rico, photographed an enormous 'A-bomb' sprite over the Carribean Sea. For a split-second, the sky lit up like this:  Oscar van der Velde, a member of the Lightning Research Group at the Universitat Politècnica de Catalunya, explains what Lucena phtographed: "This type of sprite is often called 'jellyfish' or 'A-bomb,' and ranks as the largest type of sprite in both horizontal and vertical dimensions," he says. "It consists of a bright halo approximately 85 km above Earth's surface surrounding sprite elements with long tendrils reaching down as low as ~30 km above ground level." "This kind of sprite tends to be triggered by a very impulsive positive cloud-to-ground flash," van der Velde adds. The curious thing is, Lucena did not observe an instigating lightning bolt. Instead, just before the sprite appeared, he recorded a bright point-like flash of light. "Was it a cosmic ray hitting the camera?" wonders Lucena. Play the entire video to see the flash. Another possibility: The point-like flash could have been a cloud-to-ground strike mostly eclipsed by intervening clouds. If Lucena did photograph something new triggering a sprite, perhaps it shouldn't come as a big surprise. The field is relatively new. Although sprites have been seen for at least a century, most scientists did not believe they existed until after 1989 when sprites were photographed by cameras onboard the space shuttle. There is still much to learn... Realtime Sprite Photo Gallery HERE COMES THE SOLAR WIND: A broad hole has opened up in the sun's atmosphere, and it is spewing a stream of solar wind into space. NASA's Solar Dynamics Observatory is monitoring the structure as it turns toward Earth:  Astronomers call this a "coronal hole." It is a region in the sun's outer atmosphere (corona) where magnetic fields have opened up, allowing solar wind to escape. About a week ago, a stream of solar wind flowing from this coronal hole blew past NASA's STEREO-A spacecraft at 550 km/s to 600 km/s. We can expect similar speeds when it reaches Earth on Sept. 20th, with a 30% chance of G1-class geomagnetic storms. Free: Aurora Alerts Around the Arctic Circle, green lights are already flickering. Yuichi Takasaka saw them Saturday over the Jökulsárlón Glacier Lagoon in Iceland:  Scientists have long known that equinoxes favor auroras. Around this time of year, even a slight gust of solar wind can spark beautiful Arctic lights. The timing of the incoming solar wind stream, arriving only two days before the northern autumnal equinox, could scarcely be better. Stay tuned to the aurora photo gallery for sightings. Realtime Aurora Photo Gallery Realtime Space Weather Photo Gallery Aurora alerts: text or voice | Cosmic Rays in the Atmosphere | Updated: Sept.3, 2016 // Next Flight: Sept. 10, 2016 Sept. 3, 2016: On Sept. 2nd, Spaceweather.com and the students of Earth to Sky Calculus conducted a successful transcontinental launch of two space weather balloons--one from New Hampshire and another from California. The New Hampshire balloon recorded the highest levels of atmospheric radiation since our monitoring program began two years ago. Students are reducing the data now, and we will report the results in the coming week. While you wait, here is a shot of the Atlantic coast of Maine taken during the Sept. 2nd balloon flight from an altitude of 118,000 feet:  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. Furthermore, there are studies ( #1, #2, #3, #4) linking cosmic rays with cardiac arrhythmias and sudden cardiac death in the general population. Our latest measurements show that cosmic rays are intensifying, with an increase of almost 13% since 2015:  Why are cosmic rays intensifying? The main reason is the sun. Solar storm clouds such as coronal mass ejections (CMEs) sweep aside cosmic rays when they pass by Earth. During Solar Maximum, CMEs are abundant and cosmic rays are held at bay. Now, however, the solar cycle is swinging toward Solar Minimum, allowing cosmic rays to return. Another reason could be the weakening of Earth's magnetic field, which helps protect us from deep-space radiation. 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 data points in the graph above correspond to the peak of the Reneger-Pfotzer maximum, which lies about 67,000 feet above central California. When cosmic rays crash into Earth's atmosphere, they produce a spray of secondary particles that is most intense at the entrance to the stratosphere. Physicists Eric Reneger and Georg Pfotzer discovered the maximum using balloons in the 1930s and it is what we are measuring today. THIS RESEARCH IS CROWD-FUNDED: The cosmic ray research presented on Spaceweather.com is done by students, driven by curiosity, and funded entirely by readers. Our latest flight over California on Aug. 21st was sponsored by World Tech Toys of Valencia CA. In exchange for their generous donation of $750, we flew a toy Striker Drone to the edge of space:  HD video and poster-quality images of the drone in space are now being used by World Tech Toys for marketing and outreach--an out-of-this-world bargain. Our next flights on Sept. 2nd and Sept. 10th need sponsors. Would you like to assist? Contact Dr. Tony Phillips to make arrangements. 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 Sep. 19, 2016, the network reported 6 fireballs. (6 sporadics) 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 September 19, 2016 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 | | a proud supporter of science education and Spaceweather.com | | the underlying science of space weather |  | Find homes for sale in Ocala, Orlando and Tampa with the #1 real estate company in Central Florida Local Realty Service |  | Claim your tax refund with this UK tax rebate company and get back your overpaid tax. |  | Enjoy this fabulous range of leather sofas from a leader in the UK sofa manufacturer industry.. | | These links help Spaceweather.com stay online. Thank you to our supporters! | |