Space Weather Update: 02/12/2016
By Spaceweather.com, 02/12/2016
EARTH-DIRECTED FLARE (UPDATED): Sunspot AR2497 erupted on Feb. 11th (2103 UT), producing a C9-class solar flare and hurling a coronal mass ejection (CME) in space. Newly-arriving images from SOHO show that the CME does have an Earth-directed component: movie. NOAA analysts are working now to determine the arrival time and possible effect of the CME’s impact. Stay tuned. Solar flare alerts: text or voice
LOW SOLAR ACTIVITY, BRIGHT NORTHERN LIGHTS: Solar activity was low on Feb. 10th. An outburst of auroras appeared over Tromso, Norway, anyway. Michael Zawadzki photographed the explosion of green from the aurora-shadow of the EISCAT radar:
The EISCAT radar pings the upper atmosphere, looking for disturbances related to geomagnetic activity. The antenna must have been getting good data when Zawadzki took this picture.
More auroras are in the offing. On Feb. 12th, a CIR is expected to hit Earth. CIRs, or “co-rotating interaction regions,” are transition zones between fast and slow-moving solar wind streams. Solar wind plasma piles up in these regions, producing density gradients and shock waves that do a good job of sparking auroras. NOAA forecasters say there is a 35% chance of polar geomagnetic storms when the CIR arrives. Aurora alerts: text or voice
SPY SATELLITE, LAUNCHED AND SPOTTED: On Feb. 10th, just a few hours before sunrise in California, a Delta 4 rocket blasted off from the Vandenberg AFB carrying a spy satellite for the US National Reconnaissance Office. “It was thrilling to see the launch from the Marin Headlands near San Francisco,” reports Kenneth Sperber. “The engine plume outshone the stars, disappearing after about 3 minutes.” He stacked a series of 10 second exposures to create this launch tableau:
The rocket’s payload (officially designated NROL-45) is believed to be a Topazradar-imaging satellite. It is a successor to the line of Lacrosse spy satellites, which use synthetic aperture radar (SAR) to map the Earth with a resolution comparable to optical cameras. Unlike optical cameras, however, synthetic aperture radar can penetrate clouds–a big advantage for a spysat.
Approximately, 18 hours after it was launched, NROL-45 was spotted racing among the stars over Leiden, the Netherlands:
“I could not see it with the naked eye (it was too faint even though the sky was very clear),” says photographer Marco Langbroek. “In a few days from now, after the SAR antenna has been unfolded, it will become brighter and visible with the naked eye on a good night.”
Langbroek is one of a network of international observers who have sighted NROL-45. Combining their data, they will be able to calculate the satellite’s orbit and keep track of it as it circles our planet. (So much for stealth.) More information about this may be found on Langbroek’s web site.
SOUTHERN NOCTILUCENT CLOUDS: The 2015-2016 season for noctilucent clouds (NLCs) over the southern hemisphere may soon be coming to a close. NASA’s AIM spacecraft is monitoring the clouds, and their electric-blue glow appears to be fading. This plot shows the frequency of occurrence of NLCs over Antarctica for the past nine winters; the current season is color-coded red:
“In past years of CIPS data, the southern hemisphere seasons have ended sometime between 18 February and 23 February,” says Cora Randall, a member of the AIM science team from the University of Colorado’s Laboratory for Atmospheric and Space Physics. “This means the end of the current season is probably near.”
NLCs are Earth’s highest clouds. Seeded by meteoroids, they float at the edge of space more than 80 km above the planet’s surface. The clouds are very cold and filled with tiny ice crystals. When sunbeams hit those crystals, they glow electric-blue: photo gallery.
Previous research shows that NLCs are a sensitive indicator of long-range teleconnections in Earth’s atmosphere, which link weather and climate across hemispheres. The seasonal behavior of noctilucent clouds, and how it changes from year to year, could reveal new linkages, previously unknown.
When will the last wisps of electric blue vanish? You can monitor the action right here on Spaceweather.com.
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 Feb. 11, 2016, the network reported 7 fireballs.
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 February 12, 2016 there were 1675 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
Situation Report — Oct. 30, 2015Stratospheric Radiation (+37o N)
Cosmic ray levels are elevated(+6.1% above the Space Age median). The trend is flat. Cosmic ray levels have increased +0% in the past month.
Sept. 06: 4.14 uSv/hr (414 uRad/hr)
Sept. 12: 4.09 uSv/hr (409 uRad/hr)
Sept. 23: 4.12 uSv/hr (412 uRad/hr)
Sept. 25: 4.16 uSv/hr (416 uRad/hr)
Sept. 27: 4.13 uSv/hr (413 uRad/hr)
Oct. 11: 4.02 uSv/hr (402 uRad/hr)
Oct. 22: 4.11 uSv/hr (411 uRad/hr)
These measurements are based on regular space weather balloon flights: learn more.
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. Our measurements show that someone flying back and forth across the continental USA, just once, can absorb as much ionizing radiation as 2 to 5 dental X-rays. For example, here is the data from a flight on Oct. 22, 2015:
Radiation levels peak at the entrance to the stratosphere in a broad region called the “Pfotzer Maximum.” This peak is named after physicist George Pfotzer who discovered it using balloons and Geiger tubes in the 1930s. Radiation levels there are more than 80x sea level.
Note that the bottom of the Pfotzer Maximim is near 55,000 ft. This means that some high-flying aircraft are not far from the zone of maximum radiation. Indeed, according to the Oct 22th measurements, a plane flying at 45,000 feet is exposed to 2.79 uSv/hr. At that rate, a passenger would absorb about one dental X-ray’s worth of radiation in about 5 hours.
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.
speed: 343.8 km/sec
density: 6.9 protons/cm3
explanation | more data
Updated: Today at 1411 UTX-ray Solar Flares
6-hr max: M1 1047 UT Feb12
24-hr: M1 1047 UT Feb12
explanation | more data
Updated: Today at: 1400 UTDaily Sun: 12 Feb 16AR2497 has a ‘beta-gamma’ magnetic field that harbors energy for M-classsolar flares. Credit: SDO/HMI
Sunspot number: 68
What is the sunspot number?
Updated 12 Feb 2016
Current Stretch: 0 days
2016 total: 0 days (0%)
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 12 Feb 2016
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/OvationPlanetary K-index
Now: Kp= 4 unsettled
24-hr max: Kp= 4 unsettled
explanation | more data
Interplanetary Mag. Field
Btotal: 13.8 nT
Bz: 3.7 nT north
explanation | more data
Updated: Today at 1411 UTCoronal Holes: 11 Feb 16
Solar wind flowing from this southern coronal hole could reach Earth on Feb. 16-17. Credit: SDO/AIA.Noctilucent Clouds The southern season for noctilucent clouds began on Dec. 13, 2015. It is expected to end in late February 2016.
Switch view: Ross Ice Shelf, Antarctic Peninsula, East Antarctica, PolarUpdated at: 02-12-2016 04:55:02
Updated at: 2016 Feb 11 2200 UTC
Probabilities for significant disturbances in Earth’s magnetic field are given for three activity levels: active, minor storm, severe stormUpdated at: 2016 Feb 11 2200 UTCMid-latitudes