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Solar wind
speed: 420.3 km/sec
density: 3.7 protons/cm3
explanation | more data
Updated: Today at 2351 UT
X-ray Solar Flares
6-hr max: B4
2300 UT Feb17
24-hr: B7
0644 UT Feb17
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 17 Feb 15
The magnetic field of sunspot AR2282 has decayed. It no longer poses a threat for significant solar flares. Credit: SDO/HMI

Sunspot number: 44
What is the sunspot number?
Updated 17 Feb 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%)

Update 17 Feb 2015

The Radio Sun
10.7 cm flux: 118 sfu
explanation | more data
Updated 17 Feb 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= 4
explanation | more data
Interplanetary Mag. Field
Btotal: 9.7 nT
Bz: 3.5 nT south
explanation | more data
Updated: Today at 2351 UT
Coronal Holes: 17 Feb 15
A Solar wind flowing from these polar coronal holes should reach Earth on Feb. 20-21. Credit: SDO/AIA.
Noctilucent Clouds As of Nov. 22, 2014, the season for southern hemisphere noctilucent clouds is underway. The south polar "daisy" pictured below is a composite of near-realtime images from NASA's AIM spacecraft.
Switch view: Ross Ice Shelf, Antarctic Penninsula, East Antarctica, Polar
Updated at: 02-17-2015 18:55:02
NOAA Forecasts
Updated at: 2015 Feb 17 2200 UTC
0-24 hr
24-48 hr
01 %
01 %
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 Feb 17 2200 UTC
0-24 hr
24-48 hr
30 %
05 %
10 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
30 %
15 %
40 %
05 %
Tuesday, Feb. 17, 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

THE SUN IS FLATLINING: For the 5th day in a row, solar activity remains very low. No sunspots are flaring, and the sun's X-ray output has flatlined. NOAA forecasters estimate a scant 1% chance of X-flares and a 10% chance of M-flares on Feb. 17th. Solar flare alerts: text, voice

NORTHERN LIGHTS: Auroras are dancing around the Arctic Circle as the leading edge of an approaching solar wind stream presses against Earth's magnetic field. "We had a really nice display around 9 pm local time on Feb. 16th," says Nick James, who sends this picture from Kiruna, Sweden:

The stage is set for more outbursts like James saw. Why? The interplanetary magnetic field (IMF) around Earth is tipping south, an arrangement that can open a crack in our planet's magnetosphere. If the incoming stream of solar wind pours through that crack, voila!--bright auroras. NOAA forecasters estimate a 35% chance of geomagnetic storms on Feb. 17th. Aurora alerts: text, voice

Realtime Aurora Photo Gallery

VENUS AND MARS: Venus and Mars are converging for a beautiful close encounter in the sunset sky. On Feb. 21st, the two planets will be so close together that sky watchers might lose Mars in Venus's glare. Last night, Eliot Herman photographed the pair, still relatively far apart, over Tucson, Arizona:

"There were light clouds in the fading sunlight," says Herman. "Bright Venus had a rainbow ring from the translucent cloud while the sky surrounding it was clear enough to let the stars and Mars shine through."

In only a few days, the two planets will be dramatically closer together. Their minimum separation on Feb. 21st, only 0.4o, is less than the width of a full Moon. The night before closest approach might be best of all: On Feb. 20th, the crescent Moon will pass right by the converging planets. Mark both dates on your calendar, Feb. 20th and 21st, and watch the western sky at sunset. It's a great way to end the day.

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 Feb. 17, 2015, the network reported 9 fireballs.
(9 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 February 17, 2015 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2015 CK13
Feb 15
7.2 LD
16 m
2015 CS
Feb 15
3.4 LD
22 m
2015 AZ43
Feb 15
7.7 LD
87 m
2015 CJ13
Feb 15
8.5 LD
66 m
2015 CL13
Feb 15
2 LD
32 m
2015 CQ13
Feb 18
6.7 LD
31 m
2000 EE14
Feb 27
72.5 LD
1.6 km
2063 Bacchus
Apr 7
76 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
Space Weather Alerts
  more links...
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