| | Switch to: Europe, USA, New Zealand, Antarctica Credit: NOAA/Ovation Planetary K-index Now: Kp= 2 quiet 24-hr max: Kp= 3 quiet explanation | more data Interplanetary Mag. Field Btotal: 4.4 nT Bz: 1.4 nT north more data: ACE, DSCOVR Updated: Today at 2350 UT Coronal Holes: 27 Aug 19 Earth will be strobed by solar wind flowing from these two coronal holes on Aug. 27-28 and Sept. 1-2. Credit: SDO/AIA Noctilucent Clouds They're back! After a 1-month hiatus due to a spacecraft anomaly, noctilucent cloud images from AIM have been restored. There are still lots of clouds around the Arctic Circle despite the fact that it's August when the season usually ends. Switch view: Europe, USA, Asia, Polar Updated at: 08-27-2019 17:55:02 SPACE WEATHER NOAA Forecasts | | Updated at: 2019 Aug 27 2200 UTC FLARE | 0-24 hr | 24-48 hr | CLASS M | 01 % | 01 % | CLASS X | 01 % | 01 % | Geomagnetic Storms: Probabilities for significant disturbances in Earth's magnetic field are given for three activity levels: active, minor storm, severe storm Updated at: 2019 Aug 27 2200 UTC Mid-latitudes | 0-24 hr | 24-48 hr | ACTIVE | 25 % | 10 % | MINOR | 05 % | 01 % | SEVERE | 01 % | 01 % | High latitudes | 0-24 hr | 24-48 hr | ACTIVE | 15 % | 15 % | MINOR | 15 % | 20 % | SEVERE | 05 % | 15 % | | | | | | | | | | | | Solar minimum is here - but even now strangely beautiful auroras are dancing around the poles. Deep inside the Arctic Circle, the expert guides of Aurora Holidays in Utsjoki, Finland, can help you chase them. Book now! | | | GEOMAGNETIC STORM FORECAST: Two solar wind streams are approaching Earth. The first will arrive on Aug. 27-28 followed by the second on Sept. 1-2. G1-class geomagnetic storms are possible on both dates, especially Sept. 1-2 when the second "blow" completes the double-whammy of solar wind. High-latitude sky watchers should be alert for auroras. Aurora alerts: SMS Text. WHY ARE SUNSETS TURNING PURPLE? Every year, on average, about 60 volcanoes erupt somewhere on Earth, shooting ashy plumes of sulfurous gas thousands of feet into the air. Rarely do those plumes make it all the way up to the stratosphere. This summer, however, two volcanoes have done it. The Raikoke volcano in the Kirul Islands (June 22nd) and the Ulawun volcano in New Guinea (Aug. 3rd) both punched through to the stratosphere, sending material as high as 60,000 ft. The action of these two volcanoes may explain why many sky watchers are starting to notice purple sunsets. Gabriel Cyr of Saint-Elzéar, Quebec, photographed this example on Aug. 25th: "This has got to be one of those sunsets caused by volcanic [gas] that has accumulated in the stratosphere throughout the year," says Cyr. "The skies were perfectly clear with no tropospheric clouds visible to the naked eye, making the phenomenon easier to distinguish from a 'regular' sunset." Why purple? Fine volcanic aerosols in the stratosphere scatter blue light which, when mixed with ordinary sunset red, produces a violet hue. The purple color is often preceded by a yellow arch hugging the horizon. As the sun sets, violet beams emerge from the yellow, overlapping to fill the western sky with a soft purple glow. High-quality pictures of the phenomenon often show horizontal bands cross-crossing the yellow arch. These bands are the volcanic gas. Last night, Greg Ainsworth captured many of these elements in a photo he took from Bozeman, Montana: "On Aug. 26th, I captured the purplish sunset colors, as well as horizontal banding in the yellow/orange area associated with the volcanic aerosols in the stratosphere," says Ainsworth. Sky watchers shouldn't expect to see purple every night. The volcanic gas appears to be patchily distributed, bringing strange sunsets on some nights, not all. Clear air, lack of clouds, and country settings improves their visibility. If you photograph one, send us your pictures! A sharable version of this story may be found here. Realtime Space Weather Photo Gallery Free: Spaceweather.com Newsletter YES, THAT'S A REAL PEARL: It's the first pearl in the stratosphere. On Aug. 19, 2019, the students of Earth to Sky Calculus launched a cosmic ray balloon to the edge of space, 104,002 ft high. This sterling silver pearl necklace went along for the ride: You can have it for $169.95. The students are selling these pearls to support their cosmic ray ballooning program. Each cultured "space pearl" comes with greeting card showing the necklace in flight and telling the story of its journey to the edge of space and back again. These make great birthday and Christmas gifts. Far Out Gifts: Earth to Sky Store All sales support hands-on STEM education Realtime Aurora Photo Gallery Free: Spaceweather.com Newsletter 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 Aug. 27, 2019, the network reported 30 fireballs. (30 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 August 27, 2019 there were 1983 potentially hazardous asteroids. | Recent & Upcoming Earth-asteroid encounters: Asteroid | Date(UT) | Miss Distance | Velocity (km/s) | Diameter (m) | 2019 QD | 2019-Aug-22 | 0.8 LD | 15.1 | 6 | 2019 QP2 | 2019-Aug-23 | 5.5 LD | 17.5 | 40 | 2019 QQ | 2019-Aug-25 | 10 LD | 12.2 | 32 | 2016 PD1 | 2019-Aug-26 | 11.3 LD | 5.9 | 65 | 2019 QR | 2019-Aug-27 | 11.8 LD | 7.2 | 20 | 2002 JR100 | 2019-Aug-27 | 19.4 LD | 8.4 | 49 | 2019 QS | 2019-Aug-28 | 5.5 LD | 22.6 | 41 | 2019 OU1 | 2019-Aug-28 | 2.7 LD | 13 | 102 | 2019 QP1 | 2019-Aug-31 | 10.5 LD | 8.9 | 18 | 2019 QX1 | 2019-Sep-02 | 18.9 LD | 16.8 | 30 | 2019 OF2 | 2019-Sep-03 | 18.3 LD | 10.7 | 53 | 2018 DE1 | 2019-Sep-03 | 12.7 LD | 6.6 | 28 | 2019 QE1 | 2019-Sep-05 | 13.2 LD | 6.6 | 34 | 2019 GT3 | 2019-Sep-06 | 19.5 LD | 13.6 | 218 | 2019 QZ | 2019-Sep-08 | 15.7 LD | 4.3 | 21 | 2010 RM82 | 2019-Sep-13 | 18.2 LD | 14.6 | 23 | 2013 CV83 | 2019-Sep-13 | 16.1 LD | 13.1 | 62 | 504800 | 2019-Sep-14 | 13.9 LD | 14.4 | 155 | 467317 | 2019-Sep-14 | 13.9 LD | 6.4 | 389 | 2019 JF1 | 2019-Sep-16 | 11.2 LD | 4.3 | 62 | 2018 FU1 | 2019-Sep-16 | 18.4 LD | 4.7 | 16 | 2017 SL16 | 2019-Sep-21 | 7.9 LD | 6.5 | 25 | 2017 SM21 | 2019-Sep-21 | 11.5 LD | 9.6 | 20 | 2019 QZ1 | 2019-Sep-22 | 12.5 LD | 8.2 | 77 | 523934 | 2019-Sep-24 | 10.9 LD | 22.3 | 257 | 2017 KP27 | 2019-Sep-26 | 6.2 LD | 4.8 | 25 | 2006 QV89 | 2019-Sep-27 | 18.1 LD | 4.1 | 31 | 2018 FK5 | 2019-Oct-01 | 13.3 LD | 10.5 | 8 | 2018 LG4 | 2019-Oct-02 | 13.8 LD | 8.1 | 12 | 2017 TJ4 | 2019-Oct-05 | 13.5 LD | 8.9 | 32 | 162082 | 2019-Oct-25 | 16.2 LD | 11.2 | 589 | 2017 TG5 | 2019-Oct-25 | 14.4 LD | 11.9 | 34 | 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 | SOMETHING NEW! We have developed a new predictive model of aviation radiation. It's called E-RAD--short for Empirical RADiation model. We are constantly flying radiation sensors onboard airplanes over the US and and around the world, so far collecting more than 22,000 gps-tagged radiation measurements. Using this unique dataset, we can predict the dosage on any flight over the USA with an error no worse than 15%. E-RAD lets us do something new: Every day we monitor approximately 1400 flights criss-crossing the 10 busiest routes in the continental USA. Typically, this includes more than 80,000 passengers per day. E-RAD calculates the radiation exposure for every single flight. The Hot Flights Table is a daily summary of these calculations. It shows the 5 charter flights with the highest dose rates; the 5 commercial flights with the highest dose rates; 5 commercial flights with near-average dose rates; and the 5 commercial flights with the lowest dose rates. Passengers typically experience dose rates that are 20 to 70 times higher than natural radiation at sea level. To measure radiation on airplanes, we use the same sensors we fly to the stratosphere onboard Earth to Sky Calculus cosmic ray balloons: neutron bubble chambers and X-ray/gamma-ray Geiger tubes sensitive to energies between 10 keV and 20 MeV. These energies span the range of medical X-ray machines and airport security scanners. Column definitions: (1) The flight number; (2) The maximum dose rate during the flight, expressed in units of natural radiation at sea level; (3) The maximum altitude of the plane in feet above sea level; (4) Departure city; (5) Arrival city; (6) Duration of the flight. SPACE WEATHER BALLOON DATA: 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 18% since 2015: 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. En route to the stratosphere, our sensors also pass through aviation altitudes: In this plot, 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. 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. 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 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 | | fun to read, but should be taken with a grain of salt! Forecasts looking ahead more than a few days are often wrong. | | from the NOAA Space Environment Center | | the underlying science of space weather | | To find reviews of new online casino sites in the UK try The Casino DB where there are hundreds of online casino reviews complete with bonuses and ratings. Looking for a new online casino? Try Casimpo the new site dedicated to making online casino simple and easy for all. | | These links help Spaceweather.com stay online. Thank you to our supporters! | | | | | | | | | | | | ©2018 Spaceweather.com. All rights reserved. This site is penned daily by Dr. Tony Phillips. | |