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Solar wind
speed: 475.3 km/sec
density: 3.9 protons/cm3
explanation | more data
Updated: Today at 2350 UT
X-ray Solar Flares
6-hr max: C2
2231 UT May15
24-hr: C2
0011 UT May15
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 15 May 15
The magnetic field of sunspot AR2339 has decayed, and it no longer poses a threat for major flares. Credit: SDO/HMI

Sunspot number: 126
What is the sunspot number?
Updated 15 May 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 May 2015

The Radio Sun
10.7 cm flux: 145 sfu
explanation | more data
Updated 15 May 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= 3
explanation | more data
Interplanetary Mag. Field
Btotal: 3.2 nT
Bz: 0.6 nT south
explanation | more data
Updated: Today at 2350 UT
Coronal Holes: 15 May 15

A stream of solar wind flowing from the indicated coronal hole should reach Earth on May 18-19. Credit: SDO/AIA.
Noctilucent Clouds The northern season for NLCs is about to begin. Readers should monitor the "daily daisies" below for first sightings from NASA's AIM spacecraft.
Switch view: Europe, USA, Asia, Polar
Updated at: 05-15-2015 04:55:05
NOAA Forecasts
Updated at: 2015 May 15 2230 UTC
0-24 hr
24-48 hr
20 %
20 %
05 %
05 %
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 May 15 2230 UTC
0-24 hr
24-48 hr
25 %
30 %
10 %
15 %
01 %
05 %
High latitudes
0-24 hr
24-48 hr
15 %
10 %
25 %
25 %
35 %
45 %
Friday, May. 15, 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.

Lapland tours

GLANCING BLOW ON MAY 17: NOAA forecasters estimate a 45% chance of polar geomagnetic storms on May 17th when a CME is expected to deliver a glancing blow to Earth's magnetic field. The storm cloud was hurled in our direction by a magnetic filament, which erupted away from the sun on May 13th. Aurora alerts: text, voice

SPACE WEATHER TIME MACHINE: Ten years ago today, the night sky over southern California turned blood red. "During the night and morning of May 14/15, 2005, an extreme geomagnetic storm sparked displays of the northern lights across much of the United States," recalls astrophotographer Dennis Mammana, "and we desert rats got quite a show." He took this picture from the Anza-Borrego Desert:

"On this night, the aurora danced over so wide an area of the northern sky that it required five wide-angle images stitched together to capture it all," says Mammana. "The yellowish glow along the horizon is light pollution from Palm Springs and desert cities to our north."

The display Mammana witnessed occured during the previous solar cycle, Solar Cycle 23, which was fairly strong. In those days, low-latitude auroras were not uncommon. Indeed, in the early 2000s, the staff of witnessed Northern Lights more than half a dozen times from California's Sierra Nevada mountains.

What a difference 10 years makes. Current Solar Cycle 24 is the weakest solar cycle of the Space Age--and one of the weakest of the past century. There have been no extreme geomagnetic storms, and auroras have not descended to Southern California even once.

The good news? Among researchers, it is well known that extreme geomagnetic storms favor the declining phases of solar cycles--and Solar Cycle 24 is declining! There is still hope for California auroras, after all. Aurora alerts: text, voice

Realtime Aurora Photo Gallery

VOLCANIC SUNSETS: Last month, on April 22nd, Chile's erupting Calbuco volcano blew plumes of ash and sulfurous gas more than 50,000 feet high. Since then, the swirling plumes have been spreading around the southern hemisphere. They are quite diffuse now, but still dense enough to color the sunsets of countries where they pass overhead. Just a few evenings ago, Dr. Peter Lowenstein witnessed a volcanic sunset over Murambi East, Mutare, Zimbabwe:

"Zimbabwe continues to have vivid sunsets caused by aerosols from the 22 April eruption of the Calbuco volcano," says Lowenstein. "This movie, which I made on May 10th, is a time lapse sequence of 28 photographs taken at about 20 second intervals."

The purple hue we see in Lowenstein's movie is one of the telltale signs of a volcanic sunset. Fine volcanic aerosols in the stratosphere scatter blue light which, when mixed with ordinary sunset red, produces a violet hue. Purple isn't the only color, though. Volcanic sunsets can also include a bright yellow twilight arch and long diffuse rays and shadows. All of these appeared over Zimbabwe.

Sky watchers in southern Africa, Argentina, Chile, southern parts of Brazil, Australia and New Zealand should remain alert for similar displays as Calbuco's fumes circumnavigate the southern hemisphere. Eventually the aerosols will dissipate. For now, however, the sunsets continue.

Realtime Space Weather Photo Gallery

THE 'WOW' PROMINENCE: Around the world, amateur astronomers are monitoring a magnificent structure on the sun. "I looked through my solar scope this morning, and this prominence made me catch myself saying, WOW!" reports John Nassr of Baguio, the Philippines. This is what he saw:

It's called a "hedgerow prominence." Hot glowing plasma inside the structure is held aloft by unstable solar magnetic fields. Space telescopes have taken high resolution images of similar prominences and seen amazing things: (1) tadpole-shaped plumes that float up from the base of the prominence; (2) narrow streams of plasma that descend from the top like waterfalls; and (3) swirls and vortices that resemble van Gogh's Starry Night. Got a solar telescope? Take a look!

Realtime Space Weather 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

On May. 15, 2015, the network reported 3 fireballs.
(3 sporadics)

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 May 15, 2015 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2015 JR
May 13
4 LD
24 m
2015 HB177
May 14
12.4 LD
51 m
2015 JF1
May 15
0.8 LD
10 m
2006 HX30
May 16
10.9 LD
26 m
5381 Sekhmet
May 17
62.8 LD
2.1 km
2015 JF
May 18
9 LD
24 m
2015 HT9
May 25
12.2 LD
24 m
2005 XL80
Jun 4
38.1 LD
1.0 km
2012 XB112
Jun 11
10.1 LD
2 m
2005 VN5
Jul 7
12.6 LD
18 m
2015 HM10
Jul 7
1.1 LD
68 m
1994 AW1
Jul 15
25.3 LD
1.4 km
2011 UW158
Jul 19
6.4 LD
565 m
2013 BQ18
Jul 20
7.9 LD
38 m
1999 JD6
Jul 25
18.8 LD
1.6 km
2005 NZ6
Aug 6
76.5 LD
1.4 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.
  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
  the underlying science of space weather
Space Weather Alerts
  more links...
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