 | | | Switch to: Europe, USA, New Zealand, Antarctica Credit: NOAA/Ovation  Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 3 quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 5.3 nT
Bz: -1.8 nT south
more data: ACE, DSCOVR
Updated: Today at 2250 UT Coronal Holes: 18 Dec 18 
Earth is inside a minor stream of solar wind flowing from the indicated coronal hole. Credit: SDO/AIA  Noctilucent Clouds The southern season for noctilucent clouds (NLCs) has begun! NASA's AIM spacecraft is detecting electric blue clouds at the edge of space over Antarctica. Switch view: Europe, USA, Asia, Polar Updated at: 12-18-2018 16:55:03 SPACE WEATHER
NOAA Forecasts | | Updated at: 2018 Dec 18 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: 2018 Dec 18 2200 UTC Mid-latitudes | 0-24 hr | 24-48 hr | ACTIVE | 20 % | 10 % | MINOR | 10 % | 05 % | SEVERE | 01 % | 01 % | High latitudes | 0-24 hr | 24-48 hr | ACTIVE | 20 % | 20 % | MINOR | 25 % | 20 % | SEVERE | 25 % | 15 % | | | |  | | | | | | | | | | | Lights Over Lapland has a brand-new website full of exciting adventures in Abisko National Park, Sweden! Take a look at our aurora activities and book your once-in-a-lifetime trip with us today! | | | SOLAR MINIMUM DEEPENS: The solar cycle is at low ebb. Today marks the 208th day in 2018 that the sun has been without spots, doubling the number of spotless days in 2017. The count won't be able to double again in 2019; there aren't enough days in the year! Nevertheless, we can expect a further deepening of Solar Minimum in the year ahead with, literally, hundreds of spotless days to come. Stay tuned for extra cosmic rays, long-lasting holes in the sun's atmosphere, and strangely pink auroras. Free: Aurora Alerts. THE MYSTERY OF ULTIMA THULE: When NASA's New Horizons spacecraft flew past Pluto three years ago, mission scientists watching the first close-up images were shocked. Despite being stuck in the deep freeze of the Solar System 6 billion km from the sun, Pluto was not the frozen-stiff world many expected it to be. The geography of the dethroned 9th planet was alive with mountain ranges, windswept dunes, bladed terrain and much more. In one quick flyby, New Horizons turned planetary science on its head.
Get ready to be shocked again. New Horizons is less than 2 weeks away from a new world even more mysterious than Pluto. 
Above: A speculative artist's concept of Ultima Thule with a small moon
Its name is "Ultima Thule" (2014 MU69), which means means "beyond the borders of the known world." Indeed, the little space rock is profoundly unknown. Located almost a billion kilometers farther from the sun than Pluto, Ultima Thule has never been much more than a faint speck of light in telescopes. It inhabits the distant Kuiper Belt where, seemingly, almost anything is possible.
"Really, we have no idea what to expect," says New Horizons principal investigator Alan Stern, of the Southwest Research Institute. "Will it have an atmosphere? Will it have rings? Will it have moons? Any of that could be possible, and soon we'll know the answers."
On New Year's Eve and New Year's Day, New Horizons will swoop three times closer to Ultima Thule than it flew past Pluto in July 2015, shattering previous records for the most distant body explored by a human spacecraft. First images will be posted on a web site set up by the New Horizons' team: SeeUltimaThuleNow.com 
We already know one thing about Ultima Thule. Its shape is elongated and strange. In 2017, astronomers watched a distant star pass behind Ultima Thule. Starlight winked in and out in a pattern suggesting two lobes with diameters of 20 and 18 km, respectively. Ultima Thule could be a small binary system.
"Ultima Thule is 100 times smaller than Pluto, but its scientific value is incalculable," says Stern. "From everything we know, it was formed 4.5 or 4.6 billion years ago, 4 billion miles from the sun. It has been stored at that enormous distance from the sun, at a temperature of nearly absolute zero, ever since, so it likely represents the best sample of the ancient solar nebula ever studied." "Nothing like it has ever been explored," he says. Note: A sharable permalink this story may be found here.
Realtime Space Weather Photo Gallery CHRISTMAS GIFTS FROM THE EDGE OF SPACE: So far in 2018, the students of Earth to Sky Calculus have launched 42 space weather balloons to the stratosphere, measuring cosmic rays over 3 continents, 2 hemispheres, and 7 different US states. You can help them pay their helium bill by purchasing a Christmas gift from the edge of space: 
Every item in the Earth to Sky Store has flown to the stratosphere alongside an array of cosmic ray sensors. Carried aloft by giant balloons, these unique gifts travel above 99.7% of Earth's atmosphere, experiencing space-like blasts of cosmic rays, extreme cold, and a wild ride parachuting back to Earth after the balloon explodes. Even Amazon doesn't carry items this far out! Don't forget to enter coupon code "SPACESANTA" at checkout for a 10% holiday discount. Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education GREEN COMET & GREEN AURORAS: A minor stream of solar wind is buffeting Earth's magnetic field, causing Arctic skies to fill with green auroras. Last night, Fredrik Broms of Kvaløya, Norway, photographed the display and found an extra condensation of green among the verdant waves of geomagnetic activity. It was Comet 46P/Wirtanen: 
"Despite a spectacular aurora outburst, Comet 46P/Wirtanen could still be seen through the green veils as a denser green fuzzball," says Broms. "I've never thought of auroras as light-pollution before, but what a luxurious problem. The comet was still just about possible to see with the naked eye from my location after the Moon had set - at least when the auroras kept away. What a night!" The comet might find itself surrounded by green again tonight. The solar wind continues to blow, stirring unrest in the polar magnetic field. Arctic photographers can find 46P/Wirtanen exiting the constellation Taurus en route to Capella. Sky maps: Dec. 18, 19, 20, 21. Realtime Comet Photo Gallery
Realtime Aurora 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 Dec. 18, 2018, the network reported 46 fireballs.
(28 sporadics, 9 Geminids, 3 December Monocerotids, 3 December Leonis Minorids, 2 sigma Hydrids, 1 Comae Berenicid)  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 December 18, 2018 there were 1936 potentially hazardous asteroids.
 | Recent & Upcoming Earth-asteroid encounters: | Asteroid | Date(UT) | Miss Distance | Velocity (km/s) | Diameter (m) | | 2018 XM2 | 2018-Dec-12 | 14 LD | 12.9 | 31 | | 2018 XT4 | 2018-Dec-12 | 14.6 LD | 5.1 | 18 | | 2018 XL1 | 2018-Dec-12 | 2.4 LD | 6.2 | 15 | | 2018 XJ1 | 2018-Dec-13 | 5.6 LD | 6.3 | 18 | | 2018 XF4 | 2018-Dec-13 | 7.6 LD | 14.6 | 34 | | 2018 XZ4 | 2018-Dec-13 | 12 LD | 10 | 81 | | 2015 XX169 | 2018-Dec-13 | 17 LD | 5.8 | 12 | | 2018 XE2 | 2018-Dec-14 | 10.7 LD | 21.1 | 39 | | 2018 XB5 | 2018-Dec-14 | 7 LD | 15.2 | 51 | | 2018 XG4 | 2018-Dec-15 | 2.7 LD | 7.8 | 11 | | 2018 VO9 | 2018-Dec-15 | 2.6 LD | 2.9 | 15 | | 2018 XH1 | 2018-Dec-15 | 11.6 LD | 6.7 | 25 | | 2018 XS4 | 2018-Dec-16 | 2.8 LD | 8.6 | 32 | | 2018 XR4 | 2018-Dec-17 | 5.3 LD | 11.4 | 15 | | 2018 XC4 | 2018-Dec-21 | 1.6 LD | 7.8 | 20 | | 2017 XQ60 | 2018-Dec-21 | 11.3 LD | 15.6 | 47 | | 163899 | 2018-Dec-22 | 7.4 LD | 6.2 | 1232 | | 418849 | 2018-Dec-23 | 16.6 LD | 17.6 | 269 | | 2018 XN5 | 2018-Dec-24 | 3 LD | 6.4 | 26 | | 2018 XE4 | 2018-Dec-26 | 5.4 LD | 9.4 | 18 | | 2014 AD16 | 2019-Jan-04 | 12.9 LD | 9.4 | 12 | | 2018 XO4 | 2019-Jan-06 | 7.9 LD | 4 | 30 | | 2016 AZ8 | 2019-Jan-07 | 11.6 LD | 9.1 | 224 | | 2013 YM2 | 2019-Jan-09 | 7.3 LD | 4.3 | 20 | | 2018 XN | 2019-Jan-14 | 11.9 LD | 5.6 | 59 | | 2013 CW32 | 2019-Jan-29 | 13.9 LD | 16.4 | 148 | | 2013 RV9 | 2019-Feb-06 | 17.9 LD | 5.9 | 68 | | 2017 PV25 | 2019-Feb-12 | 7.3 LD | 6.1 | 43 | 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 |  | If you are a Youtuber and want to buy real Youtube views than try out Buyrealsocial.com for the best results possible! | | 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. | |
