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. | | | GEOMAGNETIC STORMS TODAY: Minor (G1) to moderate (G2) geomagnetic storms are likely on Oct. 27th as Earth continues to move through a fast-moving stream of solar wind. Polar sky watchers should remain alert for auroras. Free: Aurora Alerts. CRAZY PINK AURORAS: During the ongoing solar wind storm, observers around the Arctic Circle have been reporting auroras of an unusual color. "Crazy pink," says Frank Meissner, who took this picture from Tromsø, Norway, on Oct. 26th: "It was awesome," he says. "Flash-like bursts were zooming all over the sky." Also watching from Tromsø, veteran observer Terence Murtagh says "even with many hundreds of aurora sightings under my belt, I've never witnessed such distinct pink colors clearly visible and bright to the naked eye. They were almost too bright to photograph properly." The pink color is probably a sign of nitrogen. Most auroras are green--a verdant glow caused by energetic particles from space hitting oxygen atoms 100 km to 300 km above Earth's surface. Seldom-seen pink appears when the energetic particles descend lower than usual, striking nitrogen molecules at the 100 km level and below. More examples may be found in the realtime photo gallery: Realtime Aurora Photo Gallery AVIATION RADIATION EXPERIMENT IN PROGRESS: Many people think that only astronauts have to worry about cosmic radiation. Not so. Regular air travelers are exposed to cosmic rays, too. This week, Spaceweather.com and the students of Earth to Sky Calculus are conducting an experiment in aviation radiation. They are flying from North America to Europe and back again to measure dose rates on international flights that cross the Arctic Circle. Here are the data they collected on Oct. 23-24 en route from Portland, Oregon, to Frankfurt, Germany: Radiation levels in the cabin of the Boeing 767 (Condor flight 2091) tripled within ten minutes after takeoff, and were nearly 40 times ground level by the time the plane reached cruising altitude at 33,000 feet. There was no solar storm in progress. The extra radiation was just a regular drizzle of cosmic rays reaching down to aviation altitudes. This radiation is ever-present and comes from supernovas, black holes, and other sources across the galaxy. The radiation sensors are the same ones that Earth to Sky Calculus routinely flies onboard helium balloons to measure cosmic rays in the stratosphere. They 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. This is part of our ongoing program to monitor radiation levels inside airplanes. Stay tuned for results from the return flight on Oct. 27th! Realtime Space Weather Photo Gallery Realtime Airglow Photo Gallery Realtime Sprite 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 Oct. 27, 2016, the network reported 20 fireballs. (14 sporadics, 3 Southern Taurids, 2 Orionids, 1 epsilon Geminid) 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 October 27, 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 | Readers, thank you for your patience while we continue to develop this new section of Spaceweather.com. We've been working to streamline our data reduction, allowing us to post results from balloon flights much more rapidly, and we have developed a new data product, shown here: This plot displays radiation measurements not only in the stratosphere, but also at aviation altitudes. Dose rates are expessed as multiples of sea level. For instance, we see that boarding a plane that flies at 25,000 feet exposes passengers to dose rates ~10x higher than sea level. At 40,000 feet, the multiplier is closer to 50x. These measurements are made by our usual cosmic ray payload as it passes through aviation altitudes en route to the stratosphere over California. What is this all about? 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 more than 12% 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. | 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 | | Visit Need An Eitzah for all your questions and forum discussions on Jewish life. | | These links help Spaceweather.com stay online. Thank you to our supporters! | |