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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 336.7 km/sec
density: 0.3 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: C1
2110 UT Apr05
24-hr: C3
1624 UT Apr05
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 04 Apr 12
Solar activity is low. None of these sunspots is actively flaring. Credit: SDO/HMI
Sunspot number: 60
What is the sunspot number?
Updated 03 Apr 2012

Spotless Days
Current Stretch: 0 days
2012 total: 0 days (0%)
2011 total: 2 days (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 821 days
Typical Solar Min: 486 days

Updated 03 Apr 2012

The Radio Sun
10.7 cm flux: 104 sfu
explanation | more data
Updated 03 Apr 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 4
explanation | more data
Interplanetary Mag. Field
Btotal: 7.6 nT
Bz: 1.2 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 04 Apr 12
A solar wind stream flowing from this southern coronal hole could brush against Earth's magnetic field on April 7th. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2012 Apr 05 2200 UTC
0-24 hr
24-48 hr
05 %
05 %
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: 2012 Apr 05 2200 UTC
0-24 hr
24-48 hr
10 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
15 %
25 %
15 %
10 %
05 %
Thursday, Apr. 5, 2012
What's up in space

Metallic photos of the sun by renowned photographer Greg Piepol bring together the best of art and science. Buy one or a whole set. They make a stellar gift.

Metallic pictures of the Sun

AURORA WATCH: A CME expected to reach Earth on April 4th is overdue. The cloud might have missed or maybe it's running late. Mindful of a possible impact, NOAA forecasters estimate a 15% chance of polar geomagnetic storms on April 5th. Aurora alerts: text, phone.

With the arrival of Spring, Arctic nights are growing shorter. "Soon, aurora season will be coming to an end," says Norwegian photographer Thorbjørn Riise Haagensen. "But it's not over yet." Last night Haagensen photographed this scene over Hillesøy, Norway:

"Beginning in the middle of May, the midnight sun brings sunshine all night long," he says. "Already some daylight is visible at the horizon at midnight. There is still enough darkness, though, for the last dance of the auroras."

more images: from Bob Conzemius of Grand Rapids, Minnesota; from Gilles Boutin of Ivujivik Nunavik Canada; from Frank Olsen of Blokken in Sortland, Norway; from Helge Mortensen of Kvaløya, Norway; from Ole C. Salomonsen of Sommarøy, Tromsø, Norway; from Thilo Bubek of Tromsø, Norway;

HEAVENLY DEJA VU: At first glance, the picture below looks exactly like thousands of others taken this week as Venus passed through the Pleaides star cluster. Look again. The date in the corner says "April 1972." Richard Keen of Boulder, Colorado, took the picture 40 years ago:

Talk about deja vu!

"Thanks to its orbit, Venus' appearance in the sky repeats itself almost exactly every 8 years," explains Keen. "Forty years ago, on April 2, 1972, Venus passed by the Pleiades only half a degree from its position two days ago. It's fun to compare this photo I took back in 1972 with this week's wonderful images."

Venus is exiting the Pleiades now, but as Keen's snapshot shows, there will be a next time--eight years from now to be exact. The next Venus-Pleaides conjunction is due in April 2020. Until then....

more images: from Miguel Claro of Fonte-de-Telha, Portugal; from John Chumack of Mill Creek, Texas; from Carl Bernhardt of Lone Pine, CA; from Laurent Laveder of Pluguffan, Brittany, France; from Aissa Moussa Mohammed of Guerrara, Ghardaia, Algeria; from Kosma Coronaios of Louis Trichardt, Limpopo Province, South Africa; from Göran Strand of Frösön, Sweden; from Alan C Tough of Elgin, Moray, Scotland; from Vesa Vauhkonen of Rautalampi, Finland; from Viktor Veres of Budapest, Hungary; from Andy Dodson of New Plymouth, New Zealand; from Amirreza Kamkar of Qayen-Iran

  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 5, 2012 there were 1287 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2012 FQ62
Apr 2
5.6 LD
29 m
2012 FS52
Apr 2
8.9 LD
47 m
2012 FH58
Apr 3
3.6 LD
16 m
2012 FA57
Apr 4
1.1 LD
27 m
2012 GD
Apr 10
9.4 LD
18 m
1996 SK
Apr 18
67.2 LD
1.6 km
2007 HV4
Apr 19
4.8 LD
8 m
2011 WV134
Apr 28
38.6 LD
1.6 km
1992 JD
May 2
9.5 LD
43 m
2010 KK37
May 19
2.3 LD
31 m
4183 Cuno
May 20
47.4 LD
5.7 km
2002 VX94
May 26
72.8 LD
1.1 km
2002 AC
Jun 16
62.2 LD
1.2 km
1999 BJ8
Jun 16
68.8 LD
1.1 km
2005 GO21
Jun 21
17.1 LD
2.2 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
Trade Show Displays
  more links...
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