Space Weather Update: 10/28/2016
By Spaceweather.com, 10/28/2016
SUBSIDING STORMS: Earth’s magnetic field is quieting on Oct. 28th following 3 days of almost uninterrupted G1– and G2-class geomagnetic storms. The storms, which mainly affected our planet’s polar regions, were caused by a high-speed solar wind stream that arrived on Oct. 25th. Earth is exiting the stream now. Free: Aurora Alerts.
CRAZY PINK AURORAS: During this week’s solar wind event, observers around the Arctic Circle reported auroras of an unusual color. “Crazy pink,” says Frank Meissner, who photographed the phenomenon on Oct. 26th from Tromsø, Norway:
“It was awesome,” he says. “Flash-like bursts were zooming all over the sky.”
Watching from Tromsø on the same night, veteran observer Terence Murtagh says “even with many hundreds of aurora sightings under my belt, I’ve never witnessed such distinct pink colors clearly visible and bright to the naked eye. They werealmost too bright to photograph properly.”
The pink color is probably a sign of nitrogen. Most auroras are green–a verdant glow caused by energetic particles from space hitting oxygen atoms 100 km to 300 km above Earth’s surface. Seldom-seen pink appears when the energetic particles descend lower than usual, striking nitrogen molecules at the 100 km level and below. More examples may be found in the realtime photo gallery:
CHINA’s NEW SPACE STATION IS SURPRISINGLY BRIGHT: China’s new space station, the Tiangong 2, isn’t very large. For comparison, the International Space Station is 5 times longer and almost 50 times more massive. Nevertheless, the newly-occupied outpost in space is surprisingly easy to see. “The Tiangong-2 with 2 taikonauts (Chinese astronauts) onboard was a spectacular sight as it passed over Fort Davis, Texas, on Oct. 23rd,” reports Gary Dowdle, who took this picture using a Sony a6300 digital camera:
“The space station was brighter than a 1st magnitude star as it maneuvered between the Bear (Ursa Major) and Cat (Lynx) heading for the Heart of the Lion (Leo),” he says. “The 42% illuminated last quarter Moon was nearby in Cancer, and the station was visible in spite of the glare.”
China’s presence in the night sky will grow even brighter in the years ahead. Taikonauts Jing Haipeng and Chen Dong are currently onboard the Tiangong 2conducting science experiments and rehearsing procedures for future missions: By the end of this decade, China plans to start launching modules for a much larger Mir-class space station slated for completion in the 2020s.
Monitoring developments is easy: Check Heavens Above for flybys of the Tiangong 2 over your backyard.
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 Oct. 28, 2016, the network reported 20 fireballs.
(16 sporadics, 3 Orionids, 1 Southern Taurid)
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 October 28, 2016 there were 1738 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: 541.4 km/sec
density: 5.7 protons/cm3
more data: ACE, DSCOVR
Updated: Today at 2221 UTX-ray Solar Flares
6-hr max: B2 2121 UT Oct28
24-hr: B3 0717 UT Oct28
explanation | more data
Updated: Today at: 2200 UTDaily Sun: 28 Oct 16Sunspot AR2603 is quiet and stable. Solar flare activity remains very low. Credit: SDO/HMI
Sunspot number: 12
What is the sunspot number?
Updated 28 Oct 2016
Current Stretch: 0 days
2016 total: 21 days (8%)
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 28 Oct 2016
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/OvationPlanetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 4 unsettled
explanation | more data
Interplanetary Mag. Field
Btotal: 7.3 nT
Bz: -3.8 nT south
more data: ACE, DSCOVR
Updated: Today at 2221 UTCoronal Holes: 28 Oct 16
Earth is inside a stream of solar wind flowing from this wide coronal hole. Credit: NASA/SDO.Noctilucent Clouds NASA’s AIM spacecraft has suffered an anomaly, and a software patch is required to fix it. As a result, noctilucent cloud images will not return until further notice. AIM science team members are optimistic that the
Switch view: Europe, USA, Asia, PolarUpdated at: 08-06-2016 16:55:02
Updated at: 2016 Oct 28 2200 UTC
Probabilities for significant disturbances in Earth’s magnetic field are given for three activity levels: active, minor storm, severe stormUpdated at: 2016 Oct 28 2200 UTCMid-latitudes