| | Switch to: Europe, USA, New Zealand, Antarctica Credit: NOAA/Ovation Planetary K-index Now: Kp= 0 quiet 24-hr max: Kp= 2 quiet explanation | more data Interplanetary Mag. Field Btotal: 4.8 nT Bz: 3.1 nT north more data: ACE, DSCOVR Updated: Today at 2351 UT Coronal Holes: 19 Aug 19 A stream of solar wind flowing from this southern coronal hole could reach Earth on Aug 21-22. Credit: SDO/AIA Noctilucent Clouds Note: an anomaly on the AIM spacecraft stopped the flow if daily NLC images on July 16th. The spacecraft has not fully recovered, but mission scientists say the outlook is good. Eventually, space-based imaging will resume. Switch view: Europe, USA, Asia, Polar Updated at: 07-18-2019 14:55:02 SPACE WEATHER NOAA Forecasts | | Updated at: 2019 Aug 19 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 19 2200 UTC Mid-latitudes | 0-24 hr | 24-48 hr | ACTIVE | 10 % | 10 % | MINOR | 01 % | 01 % | SEVERE | 01 % | 01 % | High latitudes | 0-24 hr | 24-48 hr | ACTIVE | 15 % | 15 % | MINOR | 15 % | 15 % | SEVERE | 15 % | 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! | | | VOLCANIC GASES REACH THE STRATOSPHERE AGAIN: For the second time this year, a volcano has injected sulfurous gases into the stratosphere. NASA satellites find that emissions from the Ulawun volcano in New Guinea reached the stratosphere on Aug. 3rd, following a similar eruption from the Raikoke volcano in the Kirul Islands on June 22nd. This latest ejection of SO2 could produce volcanic sunsets in the tropics and the southern hemisphere for months to come. LATE-SEASON NOCTILUCENT CLOUDS: The northern summer seasoon for noctilucent clouds (NLCs) is coming to an end, but it's not over yet. Arctic sky watchers are still seeing occasional electric-blue ripples in the twilight sky. Claire Sayers sends this picture from northern Sweden: "These night shining clouds appeared about an hour after midnight on August 16th," she says. "I photographed them using my digital camera, a 15s exposure at ISO 200." Although NLCs are a polar phenomenon, polar sky watchers seldom see them. The summer midnight sun interferes with visibility. As summer comes to an end, northern skies are darkening, allowing for midnight sightings in places like Sweden. If you live in a high-northern location, be alert for NLCs as August comes to and end--and submit your images here. Realtime Noctilucent Cloud Photo Gallery Free: Spaceweather.com Newsletter AN UNUSUAL FORM OF AURORA: You've heard of auroras--green and purple lights that dance in the sky during geomagnetic storms. But have you ever heard of an SAR? Stable Auroral Red arcs (SARs) were discovered in 1956 at the beginning of the Space Age and have been recorded by cameras on satellites hundreds of times since. Most aurora watchers have never seen an SAR, though, because they are usually invisible to the human eye. On Aug. 5th, Harlan Thomas caught one over Peyto Lake in Alberta, Canada: "I could not make it out with the naked eye," says Thomas, "but my camera captured the broad red arc in a 30 second exposure (ISO 3200). It meandered very slowly across the sky for hours, motions that distinguished it from ordinary green auroras visible in the sky that night." This sequence of images shows how the red arc lazily moved around: #1, #2, #3, #4, #5, #6, #7, #8. SARs are related to auroras, but they are not the same. Regular auroras appear when high-energy particles rain down along polar magnetic field lines, hitting the atmosphere (100-200 km high) and causing it to glow like the picture tube of an old color TV. SARs form differently. They are a sign of heat energy leaking into the upper atmosphere (~400 km high) from Earth's ring current system. SARs can become visible to the naked eye during strong geomagnetic storms. The geomagnetic storm of Aug. 5th, however, was not strong, thus requiring long camera exposures to reveal the arc. Realtime Space Weather Photo Gallery Free: Spaceweather.com Newsletter APOLLO 11 PROOF SILVER DOLLARS: The students of Earth to Sky Calculus weren't even born when Neil Armstrong and Buzz Aldrin landed on the Moon in 1969 years ago. Nevertheless, they "get it." On July 20th, the students launched 50 Apollo 11 silver dollars to the stratosphere onboard a cosmic ray balloon. The coins touched the edge of space 50 years to the day after Neil and Buzz made footprints in the Sea of Tranquillity: You can have one for $197.95. The students are selling these coins to support their cosmic ray ballooning program. Quantities are limited and more than half have already been sold. Each one comes with a greeting card showing the item in flight and telling the story of its journey to the edge of space. 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. 19, 2019, the network reported 48 fireballs. (43 sporadics, 4 Perseids, 1 Northern delta Aquariid) 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 19, 2019 there were 1983 potentially hazardous asteroids. | Recent & Upcoming Earth-asteroid encounters: Asteroid | Date(UT) | Miss Distance | Velocity (km/s) | Diameter (m) | 2019 PJ | 2019-Aug-16 | 8.8 LD | 14.2 | 60 | 2018 PN22 | 2019-Aug-17 | 17.1 LD | 2.3 | 11 | 2019 PK | 2019-Aug-18 | 11 LD | 7.4 | 30 | 2016 PD1 | 2019-Aug-26 | 11.3 LD | 5.9 | 65 | 2002 JR100 | 2019-Aug-27 | 19.4 LD | 8.4 | 49 | 2019 OU1 | 2019-Aug-28 | 2.7 LD | 13 | 95 | 2019 OF2 | 2019-Sep-03 | 18.3 LD | 10.7 | 53 | 2018 DE1 | 2019-Sep-03 | 12.7 LD | 6.6 | 28 | 2019 GT3 | 2019-Sep-06 | 19.5 LD | 13.6 | 227 | 2010 RM82 | 2019-Sep-13 | 18.2 LD | 14.6 | 23 | 2013 CV83 | 2019-Sep-13 | 15.7 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 | 61 | 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 | 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 | 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. | |