Space Weather Update: 12/07/2016
By Spaceweather.com, 12/07/2016
GEOMAGNETIC STORM WATCH: Minor G1-class geomagnetic storms are likely for the next three days as Earth passes through a high-speed stream of solar wind. The action is expected to commence on Dec. 7-8 with the arrival of a CIR (co-rotating interaction region). CIRs are transition zones between slow- and fast-moving solar wind. Solar wind plasma piles up in these regions, producing density gradients and shock waves that do a good job of sparking Arctic auroras. Solar wind blowing furiously behind the CIR could energize the light show through Dec. 10th. Free: aurora alerts
GRAB A WINDOW SEAT: Are you flying at high latitudes this week? Travel tip: Grab a window seat. Ian Griffin heeded this advice on Dec. 6th and was rewarded with the following view:
“I was on board Air Canada flight 8892 to Vancouver,” says Griffin. “Once we cleared the clouds, I couldn’t take my eyes or my camera away from the window. The auroral display 38,000 feet over Whitehorse at 6 a.m. was absolutely sublime.”
The view should improve in the nights ahead as Earth enters a stream of high-speed solar wind, sparking even brighter auroras around the Arctic Circle on Dec. 7th through 10th. Stay tuned.
AMAZING SUN HALO: Atmospheric optics expert Les Cowley has seen almost every manifestation of ice in the sky that Nature can produce. He’s not easy to impress. On Dec 6th, however, Michael Greenham of Magog, Quebec, photographed a display that impressed even Cowley:
“That is a great one,” says Cowley.
“The air temperature was -1 C on a calm December morning,” says Greenham. Sunlight hitting ice crystals in the air produced “very vivid sundogs and arcs in the sky.”
“This magnificent ice halo display isbristling with rare arcs,” says Cowley. “From top downwards we have a circumzenithal arc. Touching that is a bright and rare supralateral arc, often mistaken for the rarer 46 degree halo. Then we have a Parry arc, first recorded in 1820 by the famous Arctic explorer William Edward Parry. Touching the familiar 22 degree halo is a ‘gull-wing‘ shaped upper tangent arc. Radiating outward from the sun at far left and right are very rare helic arcs.”
Greenham spotted these halos in his front yard. Cowley knows another place to find them: “To best see halos like this choose a subzero day a few km downwind of a ski slope. Snow blowers make high quality halo forming crystals as well as snow!”
FAR-OUT STOCKING STUFFER: In space, not everything that twinkles is a star. For example, we present the Silver Stars & Moon Space Pendant:
On Dec. 3rd, using a helium balloon the students of Earth to Sky Calculuslaunched a payload full of these pendants alongside an array of cosmic ray sensors. Together they ascended to an altitude of 117,000 ft. The purpose of the sensors was to measure increasing levels of radiation in the stratosphere. The purpose of the pendants is to pay for the sensors. Our radiation monitoring program is completely crowdfunded, and the pendants are for sale.
You can have one for $69.95. Each pendant comes with a Christmas card showing the pendant at the edge of space and telling the story of its flight. More far out Christmas gifts may be found in the Earth to Sky Store. All proceeds support space weather 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. 7, 2016, the network reported 17 fireballs.
(9 sporadics, 6 sigma Hydrids, 1 Quadrantid, 1 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]
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 7, 2016 there were 1745 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: 501.3 km/sec
density: 9.8 protons/cm3
more data: ACE, DSCOVR
Updated: Today at 2303 UTX-ray Solar Flares
6-hr max: B3 1809 UT Dec07
24-hr: B3 1809 UT Dec07
explanation | more data
Updated: Today at: 2300 UTDaily Sun: 07 Dec 16Departing sunspot AR2615 poses no threat for strong solar flares. Credit: SDO/HMI
Sunspot number: 24
What is the sunspot number?
Updated 07 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 07 Dec 2016
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/OvationPlanetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 3 quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 8.1 nT
Bz: -3.2 nT north
more data: ACE, DSCOVR
Updated: Today at 2304 UTCoronal Holes: 07 Dec 16
A stream of solar wind flowing from this large coronal hole could reach Earth as early as Dec. 7-8. 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: 12-07-2016 18:55:03
Updated at: 2016 Dec 07 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 07 2200 UTCMid-latitudes