Space Weather Update: 12/05/2016
By Spaceweather.com, 12/05/2016
HERE COMES THE SOLAR WIND: If you live near the Arctic Circle, get ready for Northern Lights. A solar wind stream is approaching Earth with wind speeds as high as 700 km/s. First contact with the fast-moving gas on Dec. 7th and 8th could produce G1-class geomagnetic storms and auroras at high latitudes.
The source of this solar wind stream is a hole in the sun’s atmosphere, shown here in a Dec. 5th image from NASA’s Solar Dynamics Observatory:
This is a “coronal hole”–a region where the sun’s magnetic field has opened up, allowing solar wind to escape. Because this hole is broad, the emerging stream of solar wind is broad as well. It should influence Earth for several days after it arrives. Free: Aurora Alerts.
RED AIRGLOW OVER EUROPE: After nightfall on Dec. 2nd, the sky above Hungary suddenly became impressed by luminous ripples. “It was a once in a lifetime display of airglow in the middle of the light-polluted Europe,” reports eye-witness Monika Landy-Gyebnar. Andras Pinter photographed the red corrugations outside the city of Mihályi:
“It was a very-very strong airglow above Hungary,” says Pinter, who put together this animation to show the dynamics of the display.
Airglow is aurora-like phenomenon caused by chemical reactions in the upper atmosphere. Human eyes seldom notice the faint glow, but “on Dec. 2nd it was easily visible to the naked eye,” adds Landy-Gyebnar. “To the layman, the bands might have looked like a layer of pale thin clouds, but my camera revealed their telltale red color.”
The red color of the display was remarkable. Airglow is usually green, the color of light from oxygen atoms some 90 km to 100 km above Earth’s surface. Where does the red come from? Instead of oxygen, OH can produce the required color. These neutral molecules (not to be confused with the OH- ion found in aqueous solutions) exist in a thin layer 85 km high where gravity waves impress the red glow with a dramatic rippling structure.
Meanwhile in Slovakia, the usual green color was visible through gaps in clouds. Roman Vanur photographed it from the city of Počúvadlo. “A great display!” he says.
Airglow is more common than you think. Browse the airglow gallery for more apparitions.
I HEART PLUTO: Did you know that cosmic radiation in Earth’s atmosphere is increasing? It’s true. These and other findings of the Earth to Sky Calculusballooning program are funded not by government grants or corporate donations. Instead, we rely on crowdfunding. Hence, the “I Heart Pluto” Christmas ornament:
To raise funds for their ongoing research, on Dec. 3rd Spaceweather.com and the students of Earth to Sky Calculus flew a payload-full of these ornaments to the stratosphere. You can have one for $59.95.
The ceramic disk highlights Tombaugh Regio–a.k.a. “Pluto’s heart”–discovered by NASA’s New Horizons spacecraft when it flew past Pluto in July 2015. The heart-shaped region is geologically active with glacial flows and towering mountains of ice. Some researchers think the icy crust of Pluto’s Heart caps an underground ocean of liquid water. An ocean of water at the edge of the solar system? Think about *that* when you see this ornament hanging from your Christmas tree.
The “I Heart Pluto” ornament and other edge of space gifts may be found in the Earth to Sky Store. All proceeds are used to support cutting-edge student research.
All Sky Fireball Network
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. 5, 2016, the network reported 22 fireballs.
(16 sporadics, 5 sigma Hydrids, 1 November omega Orionid)
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]
Near Earth Asteroids
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 5, 2016 there were 1744 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:Asteroid
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.
speed: 331.3 km/sec
density: 11.9 protons/cm3
more data: ACE, DSCOVR
Updated: Today at 1924 UTX-ray Solar Flares
6-hr max: B2 1715 UT Dec05
24-hr: C1 0607 UT Dec05
explanation | more data
Updated: Today at: 1900 UTDaily Sun: 05 Dec 16Sunspot AR2615 is crackling with C-class solar flares. Credit: SDO/HMI
Sunspot number: 37
What is the sunspot number?
Updated 05 Dec 2016
Current Stretch: 0 days
2016 total: 25 days (7%)
2015 total: 0 days (0%)
2014 total: 1 day (<1%)
2013 total: 0 days (0%)
2012 total: 0 days (0%)
2011 total: 2 days (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Updated 05 Dec 2016
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/OvationPlanetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 2 quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 2.9 nT
Bz: -2.8 nT south
more data: ACE, DSCOVR
Updated: Today at 1923 UTCoronal Holes: 05 Dec 16
A large coronal hole is turning toward Earth. Credit: NASA/SDO.Noctilucent Clouds The southern season for noctilucent clouds began on Nov. 17th. Come back to this spot every day to see the “daily daisy” from NASA’s AIM spacecraft, which is monitoring the dance of electric-blue around the Antarctic Circle.
Switch view: Ross Ice Shelf, Antarctic Peninsula, East Antarctica, PolarUpdated at: 12-05-2016 16:55:05
Updated at: 2016 Dec 04 2200 UTC
Probabilities for significant disturbances in Earth’s magnetic field are given for three activity levels: active, minor storm, severe stormUpdated at: 2016 Dec 04 2200 UTCMid-latitudes