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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 555.1 km/sec
density: 1.2 protons/cm3
explanation | more data
Updated: Today at 2349 UT
X-ray Solar Flares
6-hr max: C1
2202 UT Dec15
24-hr: C1
2202 UT Dec15
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 15 Dec 15
Sunspot AR2470 poses a slight threat for M-class solar flares. Credit: SDO/HMI

Sunspot number: 81
What is the sunspot number?
Updated 15 Dec 2015

Spotless Days
Current Stretch: 0 days
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 15 Dec 2015


The Radio Sun
10.7 cm flux: 124 sfu
explanation | more data
Updated 15 Dec 2015

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/Ovation
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 5
storm
explanation | more data
Interplanetary Mag. Field
Btotal: 8.2 nT
Bz: 6.8 nT south
explanation | more data
Updated: Today at 2348 UT
Coronal Holes: 15 Dec 15

Solar wind flowing from the indicated coronal hole should reach Earth on ~Dec. 17th. Credit: SDO/AIA.
Noctilucent Clouds The southern season for noctilucent clouds is about to begin. Monitor the daily daisies, below, from NASA's AIM spacecraft for the first wisps of electric blue above Antarctica.
Switch view: Ross Ice Shelf, Antarctic Peninsula, East Antarctica, Polar
Updated at: 12-15-2015 17:55:03
SPACE WEATHER
NOAA Forecasts
Updated at: 2015 Dec 15 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
10 %
10 %
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: 2015 Dec 15 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
10 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
15 %
MINOR
30 %
20 %
SEVERE
25 %
15 %
 
Tuesday, Dec. 15, 2015
What's up in space
 

Marianne's Heaven On Earth Aurora Chaser Tours Chasethelighttours.co.uk invites you to join them in their quest to find and photograph the Aurora Borealis. Experience the winter wonderland in the Tromsø Area.

 
Chase the Light Tours

QUIET WITH A SLIGHT CHANCE OF FLARES: With no sunspots actively flaring, solar activity is low. One sunspot could break the quiet: AR2470 is large and has a magnetic field that harbors energy for significant explosions. NOAA forecasters estimate a 15% chance of M-class flares on Dec. 15th. Solar flare alerts: text or voice

GEMINID METEOR UPDATE: Last night, Dec. 14-15, NASA's network of all-sky meteor cameras detected 148 Geminid fireballs over the USA. The shower was supposed to peak on Dec. 13-14. These data suggest, however, that the Geminids are still active. Earth remains inside a stream of gravelly debris from "rock comet" 3200 Phaethon, the shower's source. Jeff Dai caught this Geminid disintegrating over Bhaktapur Durbar Square in Nepal on Dec. 15th:

"The Geminids were so bright and active that I could see them through the lights of the city," says Dai. "Bhaktapur Durbar Square is the plaza in front of the royal palace of the old Bhaktapur Kingdom. It is one of three Durbar Squares in the Kathmandu Valley in Nepal, all of which are UNESCO World Heritage Sites."

Worldwide observers have reported meteor rates as high as 100 per hour in dark-sky locations. Counts should decline tonight, Dec. 15-16, as Earth begins to leave the debris stream. For now, though, the Geminids remain active. The best time to look is during the dark hours between local midnight and dawn.

Realtime Meteor Photo Gallery

POLAR STRATOSPHERIC CLOUDS: An outbreak of polar stratospheric clouds (PMCs) is underway around the Arctic Circle. Unlike normal grey-white clouds, which hug Earth's surface at altitudes of only 5 to 10 km, PMCs float through the stratosphere (25 km) and they are fantastically colorful. Sarah Skinner saw this specimen high above Abisko, Sweden:

"Just as I was heading out to de-ice the car on Dec. 14th, I looked up and noticed the most incredible cloud formation," says Skinner. "At the same time, an excited text came through from my boss, aurora tour guide Chad Blakley, who having lived here for many years has seen this only once or twice and explained to an Arctic newbie like me how rare these formations really are."

Also known as "nacreous" or "mother of pearl" clouds, the icy structures form in the lower stratosphere when temperatures drop to around minus 85ºC. Sunlight shining through tiny ice particles ~10µm across produce the characteristic bright iridescent colors by diffraction and interference. Once thought to be mere curiosities, some PMCs are now known to be associated with the destruction of ozone.

"Nacreous clouds far outshine and have much more vivid colours than ordinary iridescent clouds, which are very much poor relations and seen frequently all over the world," writes atmospheric optics expert Les Cowley. "Once seen they are never forgotten."

Realtime Space Weather Photo Gallery

GEOMAGNETIC STORMS: A co-rotating interaction region (CIR) struck Earth's magnetic field on Dec. 14th, followed shortly thereafter by a high-speed stream of solar wind. The double jolt sparked almost 9 hours of G1-class geomagnetic storms and auroras around the Arctic Circle. Brian Whittaker saw the display from the cockpit of an airplane 35,000 feet above Northern Manitoba, Canada:

"In addition to the auroras, the Geminid meteor shower was very active," says Whittaker.

More auroras are in the offing on Dec. 15th. NOAA forecasters estimate a 60% chance of continued storming as the solar wind continues to blow. Aurora alerts: text or voice

Realtime Aurora Photo Gallery


Realtime Comet Photo Gallery


  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. 15, 2015, the network reported 244 fireballs.
(143 Geminids, 90 sporadics, 4 December Leonis Minorids, 2 , 2 sigma Hydrids, 1 December Monocerotid, 1 , 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]

  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 15, 2015 there were 1645 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Size
2015 XU169
Dec 10
9.5 LD
16 m
1998 WT24
Dec 11
10.9 LD
1.1 km
2015 XA169
Dec 12
7.4 LD
15 m
2015 XR169
Dec 13
1.3 LD
8 m
2015 XX128
Dec 14
2.4 LD
25 m
2015 XX169
Dec 14
8.4 LD
15 m
2015 XN55
Dec 15
2.5 LD
15 m
2015 XY261
Dec 15
0.8 LD
16 m
2015 XL261
Dec 17
9.7 LD
38 m
2015 XE1
Dec 19
13.2 LD
29 m
2015 XN261
Dec 23
2.6 LD
29 m
2011 YD29
Dec 24
9.7 LD
24 m
2003 SD220
Dec 24
28.4 LD
1.8 km
2008 CM
Dec 29
22.8 LD
1.5 km
2015 XV351
Dec 29
5.3 LD
28 m
2015 XC352
Dec 30
5.2 LD
29 m
2004 MQ1
Jan 2
55.4 LD
1.1 km
1999 JV6
Jan 6
12.6 LD
410 m
1685 Toro
Jan 22
60.9 LD
1.7 km
2001 XR1
Jan 23
74.4 LD
1.5 km
2015 VC2
Jan 28
5.8 LD
15 m
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, 2015 Stratospheric 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. Here is the data from our latest flight, Oct. 22nd:

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.

  Essential web links
NOAA Space Weather Prediction Center
  The official U.S. government space weather bureau
Atmospheric Optics
  The first place to look for information about sundogs, pillars, rainbows and related phenomena.
Solar Dynamics Observatory
  Researchers call it a "Hubble for the sun." SDO is the most advanced solar observatory ever.
STEREO
  3D views of the sun from NASA's Solar and Terrestrial Relations Observatory
Solar and Heliospheric Observatory
  Realtime and archival images of the Sun from SOHO.
Daily Sunspot Summaries
  from the NOAA Space Environment Center
Heliophysics
  the underlying science of space weather
Synergy Spray Foam Insulation of Houston TX
  Protection from the Sun!
Kotton Grammer, Search Engine Marketing
  a sponsor of SpaceWeather.com
Columbia Northern High School
  Web-based high school science course with free enrollment
Heliophysics
  the underlying science of space weather
  more links...
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