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Solar wind
speed: 451.3 km/sec
density: 3.0 protons/cm3
explanation | more data
Updated: Today at 2348 UT
X-ray Solar Flares
6-hr max: B3
2252 UT Jul23
24-hr: B3
2252 UT Jul23
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 23 Jul 15
None of these sunspots has the type of unstable magnetic field that poses a threat for strong solar flares. Solar activity is low. Credit: SDO/HMI

Sunspot number: 35
What is the sunspot number?
Updated 23 Jul 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 23 Jul 2015


The Radio Sun
10.7 cm flux: 89 sfu
explanation | more data
Updated 23 Jul 2015

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/Ovation
Planetary K-index
Now: Kp= 4 unsettled
24-hr max: Kp= 5
storm
explanation | more data
Interplanetary Mag. Field
Btotal: 8.0 nT
Bz: 1 nT south
explanation | more data
Updated: Today at 2348 UT
Coronal Holes: 23 Jul 15

Solar wind flowing from the bgsh indicated coronal hole could reach Earth on July 25-26. Credit: SDO/AIA.
Noctilucent Clouds The northern season for NLCs is underway. NASA's AIM spacecraft spotted the first noctilucent clouds over the Arctic Circle on May 19th.
Switch view: Europe, USA, Asia, Polar
Updated at: 07-23-2015 15:55:08
SPACE WEATHER
NOAA Forecasts
Updated at: 2015 Jul 23 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
01 %
01 %
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 Jul 23 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
25 %
20 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
30 %
30 %
SEVERE
30 %
25 %
 
Thursday, Jul. 23, 2015
What's up in space
 

Learn to photograph Northern Lights like a pro. Sign up for Peter Rosen's Aurora Photo Courses in Abisko National Park, winner of the TripAdvisor Certificate of Excellence Award 2015.

 
Lapland tours

(ALMOST) NO CHANCE OF FLARES: Solar activity is very low. With no sunspots actively flaring, the sun's X-ray output has flatlined. NOAA forecasters estimate a 5% chance of M-class flares and no more than a 1% chance of X-flares on July 23rd. [forecast video] Solar flare alerts: text or voice.

GEOMAGNETIC STORM: A mild (Kp=5) geomagnetic storm broke out during the early hours of July 23rd when a disturbance in the solar wind hit Earth's magnetic field. Before sunrise, Northern Lights were sighted in multiple northern-tier US states. Sarah D'Angelo sends this picture from Paradise, Michigan:

"With the sun rising quickly, there wasn't much time to find a picturesque spot," she says. "I set a tripod in front of my house and hoped for the best. The colors were gorgeous. Very bright!"

The solar wind disturbance was likely related to a CME expected to sideswipe Earth today. High-latitude sky watchers should remain alert for auroras tonight as our planet passes through the CME's wake. Aurora alerts: text or voice.

Realtime Aurora Photo Gallery

RADS ON A PLANE: Many people think you have to be an astronaut to experience space weather. Not so. All you have to do is step onboard a commercial aircraft. This week, Spaceweather.com's Dr. Tony Phillips and the students of Earth to Sky Calculus flew across the United States to conduct a transcontinental launch of space weather balloons. They took radiation sensors onboard the plane to find out how much radiation they would absorb during the flight. Answer: quite a bit. Here are the data they collected:

Radiation levels in the cabin of the Airbus 319 (Spirit Airlines FL640) tripled within ten minutes after takeoff, and were nearly 30 times ground level by the time the plane reached cruising altitude at 39,000 feet. During the 3+ hour flight, the sensors accumulated more than a year's worth of natural radiation on the ground.

There was no solar storm in progress. The extra radiation was just a regular drizzle of cosmic rays reaching down to aviation altitudes. This radiation is ever-present and comes from supernovas, black holes, and other sources across the galaxy. Solar activity modulates the intensity of cosmic rays. Gusts of solar wind and CMEs can actually cause radiation levels to drop by sweeping aside cosmic rays near Earth. Periods of low solar activity, on the other hand, allow radiation levels to rise.

Solar activity is not the only variable: Radiation levels vary within the plane itself. Different-colored lines in the data plot, above, represent different locations inside the cabin. On this particular flight, dose rates were highest in First Class and lowest near the toilets in the rear. This gradient is not understood; presumably, it has something to do with the way the fuselage and fuel tanks interact with energetic particles. The altitude of the plane matters as well. When the cruising altitude increased about two hours into the flight, dose rates increased accordingly. All of these factors make radiation levels onboard airplanes unpredictable.

The radiation sensors are the same ones that Earth to Sky Calculus routinely flies onboard helium balloons to measure cosmic rays in the stratosphere. They 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.

Stay tuned for updates from the return flight.

Realtime Space Weather Photo Gallery


Realtime Sprite Photo Gallery


Realtime NLC 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 Jul. 23, 2015, the network reported 12 fireballs.
(10 sporadics, 2 alpha Capricornids)

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 July 23, 2015 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Size
1994 AW1
Jul 15
25.3 LD
1.3 km
2011 UW158
Jul 19
6.4 LD
540 m
2013 BQ18
Jul 20
7.9 LD
38 m
2015 OQ21
Jul 24
1.5 LD
11 m
1999 JD6
Jul 25
18.8 LD
1.6 km
2005 NZ6
Aug 6
76.5 LD
1.4 km
2005 JF21
Aug 16
20.1 LD
1.6 km
2004 BO41
Aug 31
57.3 LD
1.2 km
1991 CS
Sep 4
62.1 LD
1.4 km
2014 KS76
Sep 14
8.7 LD
22 m
2004 TR12
Sep 15
58.8 LD
1.0 km
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.
  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
Columbia Northern High School
  Web-based high school science course with free enrollment
  more links...
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