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Solar wind
speed: 348.7 km/sec
density: 7.4 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: C9
1807 UT Apr12
24-hr: M1
0952 UT Apr12
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 12 Apr 15
Big sunspot AR2321 has a 'beta-gamma' magnetic field that harbors energy for M-class solar flares. . Credit: SDO/HMI

Sunspot number: 74
What is the sunspot number?
Updated 12 Apr 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 12 Apr 2015

The Radio Sun
10.7 cm flux: 123 sfu
explanation | more data
Updated 12 Apr 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= 1
explanation | more data
Interplanetary Mag. Field
Btotal: 5.7 nT
Bz: 2.9 nT south
explanation | more data
Updated: Today at 2348 UT
Coronal Holes: 12 Apr 15

Solar wind flowing from this southern coronal hole could reach Earth as early as April 15-16. Credit: SDO/AIA.
Noctilucent Clouds The southern season for NLCs has come to an end. The last clouds were observed by NASA's AIM spacecraft on Feb. 20, 2015. Now attention shifts to the northern hemisphere, where the first clouds of 2015 should appear in mid-May.
Switch view: Ross Ice Shelf, Antarctic Penninsula, East Antarctica, Polar
Updated at: 02-28-2015 02:55:03
NOAA Forecasts
Updated at: 2015 Apr 12 2200 UTC
0-24 hr
24-48 hr
55 %
55 %
20 %
20 %
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 Apr 12 2200 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
20 %
20 %
10 %
10 %
Sunday, Apr. 12, 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

INCREASING CHANCE OF FLARES: Today, NOAA forecasters have boosted the odds of an M-class solar flare to 40%. The reason: A large and potentially active sunspot is emerging over the sun's northeastern limb. Giuseppe Petricca sends this picture of the behemoth from Sulmona, Abruzzo, Italy:

"The sunspot looks really great, with many structures around and in the middle of it!" reports Petricca.

Numbered AR2321, this sunspot has an unstable 'beta-gamma' magnetic field that harbors energy for strong eruptions--maybe even X-flares. NOAA puts the odds of an X-class eruption at 15%.

Sprawling more than 120,000 km from end to end, the sunspot group has several dark cores larger than Earth. These dimensions make AR2321 an easy target for backyard solar telescopes. If you have one, take a look. Solar flare alerts: text, voice

Realtime Space Weather Photo Gallery

VENUS AND THE SEVEN SISTERS, DRESSED IN GREEN: Around the world, sky watchers have been enjoying the close encounter between Venus and the Pleiades star cluster, visible every evening in the western sky after sunset. On April 11th, photographer Jerry Magnum Porsbjer of Moskosel, Sweden, went outside to see the show and got more than he expected: "There appeared some auroral rays like sharp beams around Venus and the Pleiades," he says.

"I rapidly attached a telephoto lens to my camera and got this interesting photo," he says. "In the picture you can see the aurora, Venus, the Pleiades and a satellite--the short dash top right. A few seconds later all the aurora rays were gone! It was brief but beautiful."

You don't have to live in the Arctic for a beautiful view of the conjunction. When the sun goes down tonight, step outside and look west as the sky fades to black. The bright Goddess of Love is only a few degrees from the delicate Seven Sisters. It's a nice way to end the day--no auroras required.

Realtime Space Weather Photo Gallery

GOODBYE WINTER, HELLO SUMMER: Around the Arctic Circle, the summer sun is rising and, as a result, night is disappearing. "Our seasons are changing," says Thomas Kast of Siikajoki, Finland, who photographed the transition on April 10th:

"Just a week ago, the Gulf of Bothnia was still completely frozen here," says Kast. "Now only the ice in the boat marina (on the left side of the photo) is still intact. If you look closely on the right side of the photo, you will see a wobbly line from ice floes drifting in the waves."

"On the horizon, the afterglow from the sunset was visible for many hours," he adds. "Due to the aftereffects of the G2-class geomagnetic storm, auroras were visible to the eye very early."

This photo says it all: "Goodbye winter, hello summer."

Realtime Aurora Photo Gallery

Realtime Eclipse 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 Apr. 12, 2015, the network reported 4 fireballs.
(4 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 April 12, 2015 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2063 Bacchus
Apr 7
76 LD
1.6 km
2015 GZ
Apr 7
8.7 LD
27 m
2015 GU
Apr 12
0.3 LD
9 m
2005 KA
Apr 12
13 LD
50 m
2015 GE1
Apr 13
3.4 LD
30 m
2015 GL
Apr 13
6 LD
39 m
2015 GB1
Apr 13
6 LD
20 m
2015 GK
Apr 13
2.8 LD
29 m
2015 GA1
Apr 16
2.5 LD
20 m
5381 Sekhmet
May 17
62.8 LD
2.1 km
2005 XL80
Jun 4
38.1 LD
1.0 km
2012 XB112
Jun 11
10.1 LD
2 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.
  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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