It's waiting for you: The most successful Aurora Photo Tour on Earth! 100% success rate 4 years in a row and winner of the TripAdvisor Certificate of Excellence Award. Join LapplandMedia's aurora tours in Abisko, Swedish Lapland! | | | SOLAR SECTOR BOUNDARY CROSSING: Late on May 25th, Earth will cross a fold in the heliospheric current sheet and enter a region of space filled with negative polarity magnetic fields. Such fields can open a crack in Earth's magnetosphere, allowing solar wind to pour in and fuel geomagnetic disturbances. According to NOAA forecasters, the odds of a G1-class storm is 20% to 30%. Aurora alerts: text, voice. WAITING FOR NOCTILUCENT CLOUDS: Every year in late May, noctilucent clouds (NLCs) gather over Earth's north pole where they remain, rippling hypnotically, until the end of Arctic summer. NLCs are, by far, Earth's highest clouds. Seeded by meteoroids, they float in a thin layer ~83 km above the planet's surface. With the beginning of the season upon us, NASA's AIM spacecraft is monitoring the Arctic for signs of electric blue: This is called a "daily daisy." It assembles scans from AIM's Cloud Imaging and Particle Size (CIPS) instrument into an ensemble picture of the Arctic. Noctilucent clouds would appear as wispy filaments criss-crossing the Arctic Circle. You can see the daily daisy updated every 24 hours right here on Spaceweather.com. So far AIM's daily daisy is empty--no NLCs. There has been one ground-based sighting that suggests the season might already be underway. We will know for sure when AIM spots the first Arctic NLCs of 2016 from space. Realtime Noctilucent Cloud Photo Gallery POLAR MESOSPHERIC SUMMERTIME ECHOS: Noctilucent clouds aren't the only sign of Arctic summer. So are polar mesospheric summertime echos (PMSEs). Arctic researchers who monitor VHF radio receivers sometimes pick up late night signals from distant transmitters. These strange "echos" occur during the months from May through August, the same as noctilucent cloud season. On May 14th, Rob Stammes of Laukvik, Lofoten, Norway, may have recorded the first PMSEs of 2016: "I use my VHF receiving system generally for signals from auroras and meteors," says Stammes. "This couldn't have been auroras, because aurora activity was low. Plus, there is a big difference between the sound from aurora echoes and the sound of other reflection mechanisms. This event was much more like a PMSE, which I have detected many times in previous seasons." PMSEs are radio waves reflection from an altitude of 80 km to 90 km. That part of Earth's upper atmosphere is called the "mesosphere." It is, coincidentally, the same place noctilucent clouds are found. The exact cause of PMSEs is not yet known; theorists have proposed explanations ranging from steep electron density gradients and "dressed aerosols" to gravity waves and turbulence. The echoes are often accompanied by visible NLCs, but not always. Arctic summer is coming. Stay tuned for more PMSEs. Realtime Space Weather Photo Gallery SNOOPY AT THE EDGE OF SPACE: On May 15th, Spaceweather.com and the students of Earth to Sky Calculus launched Snoopy to the edge of space--and set a high-altitude record for political campaigning. The high-altitude balloon flight was sponsored by Inyo County Supervisor Jeff Griffiths, who is running for re-election. Snoopy carried his campaign pin 115,700 feet: Griffith's generous donation to the students not only paid for his Edge of Space campaign ad, but also allowed us to continue our atmospheric radiation monitoring program. Valuable data were collected by cosmic ray sensors inside the payload, confirming our previous finding that cosmic rays are intensifying. Thanks, Jeff! Readers, if you would like to send a small item or photo to space--and sponsor student research at the same time--the cost is $500. Contact Dr. Tony Phillips to book your flight. 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 May. 24, 2016, the network reported 12 fireballs. (12 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 May 24, 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. | 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. For example, here is the data from a flight on Oct. 22, 2015: 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 | | 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.. | |