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Solar wind
speed: 357.1 km/sec
density: 6.7 protons/cm3
explanation | more data
Updated: Today at 2351 UT
X-ray Solar Flares
6-hr max: M1
1820 UT Jun21
24-hr: M3
0944 UT Jun21
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 21 Jun 15
Sunspot AR2371 has a 'beta-gamma-delta' magnetic field that harbors energy for X-class solar flares. Credit: SDO/HMI

Sunspot number: 89
What is the sunspot number?
Updated 21 Jun 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 21 Jun 2015

The Radio Sun
10.7 cm flux: 135 sfu
explanation | more data
Updated 21 Jun 2015

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/Ovation
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 4
explanation | more data
Interplanetary Mag. Field
Btotal: 11.5 nT
Bz: 5.0 nT north
explanation | more data
Updated: Today at 2352 UT
Coronal Holes: 21 Jun 15

Solar wind flowing from the indicated coronal hole should reach Earth on June 24-25. 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: 06-20-2015 17:55:04
NOAA Forecasts
Updated at: 2015 Jun 21 2200 UTC
0-24 hr
24-48 hr
75 %
75 %
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 Jun 21 2200 UTC
0-24 hr
24-48 hr
15 %
30 %
35 %
40 %
50 %
25 %
High latitudes
0-24 hr
24-48 hr
01 %
05 %
10 %
15 %
90 %
85 %
Sunday, Jun. 21, 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

CME IMPACT, MORE TO COME: A minor CME hit Earth's magnetic field on June 21st at approximately 1600 UT. The weak impact did not cause an immediate geomagnetic storm. At least two more CMEs are en route, including the full-halo CME described below. This means geomagnetic storms remain possible in the nights ahead despite the muted effect of today's strike. Aurora alerts: text, voice

FULL HALO CME: Sunspot AR2371 erupted on June 21st at 01:42 UT, producing an M2-class solar flare and a full-halo CME. Click to view a movie of the storm cloud, which is heading directly for Earth:

Geomagnetic storms are likely when the CME reaches Earth, probably on June 23rd or 24th. Its impact will add to that of two lesser CMEs already en route. NOAA analysts are modeling the full-halo CME now and, shortly, they will give their estimates for its arrival time and the severity of the resulting storm. Stay tuned for updates. Aurora alerts: text, voice

Realtime Aurora Photo Gallery

HAPPY SOLSTICE: Today is the June solstice--the longest day of the year in the northern hemisphere, and the shortest day in the south. The exact moment of the solstice is 12:38 pm EDT, when the sun reaches its highest declination on the celestial sphere (+23.5o). To mark the occasion, Richard Sears photographed this sun halo over Atwater, California:

"Happy solstice!" says Sears.

The long days of northern summer are excellent times to look for sun halos. They are formed by ice crystals in high cirrus clouds, which are freezing cold no matter how hot it gets on the ground below. Keep an eye on the solstice sun for rainbow-colored arcs in the surrounding sky.

Realtime Space Weather Photo Gallery

SUNSET SKY SHOW--IT'S NOT OVER YET: All weekend long, people around the world watched with pleasure as Venus, Jupiter, and the slender cresent Moon converged in the sunset sky. Pavel Gabzdyl photographed the triangular conjunction over Brno, Czech Republic:

"The three bright lights were visible even before the sun set," says Gabzdyl. "We could not take our eyes off of them."

As the new week unfolds, the Moon is moving away from the planets--but the show is far from over. In the evenings ahead, Venus and Jupiter will draw closer and closer to one another. On June 30th, they will be a jaw-dropping 1/3rd of a degree apart.  You'll be able to hide the pair behind your little pinky finger outstretched at arm's length. Such a close pairing of bright planets is truly mesmerizing. Mark your calendar and enjoy the show!

Realtime Space Weather Photo Gallery

Realtime NLC Photo Gallery

Realtime Sprite 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 Jun. 19, 2015, the network reported 7 fireballs.
(7 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 June 21, 2015 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2015 LK
Jun 17
7.9 LD
36 m
2015 LG
Jun 18
8.8 LD
54 m
2015 LQ21
Jun 18
13 LD
65 m
2015 LR21
Jun 20
2.5 LD
23 m
2015 KK57
Jun 23
8.3 LD
14 m
2015 MN11
Jun 24
12.5 LD
57 m
2005 VN5
Jul 7
12.6 LD
18 m
2015 HM10
Jul 7
1.1 LD
81 m
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
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
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
Columbia Northern High School
  Web-based high school science course with free enrollment
  more links...
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