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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 415.8 km/sec
density: 0.7 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Apr21
24-hr: A0
2340 UT Apr21
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 21 Apr 09
A new sunspot is forming at the circled location. The magnetic polarity of the spot identifies it as a member of new Solar Cycle 24. Credit: SOHO/MDI
Sunspot number: 7
What is the sunspot number?
Updated 21 Apr 2009

NEW: Spotless Days
Current Stretch: 0 days
2009 total: 97 days (88%)
Since 2004: 608 days
Typical Solar Min: 485 days
explanation | more info
Updated 21 Apr 2009

Far side of the Sun:
This holographic image reveals no sunspots on the far side of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 3.0 nT
Bz: 1 nT south
explanation | more data
Updated: Today at 2347 UT
Coronal Holes:
There are no large coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Apr 21 2201 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: 2009 Apr 21 2201 UTC
0-24 hr
24-48 hr
10 %
05 %
05 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
10 %
05 %
05 %
01 %
01 %
01 %
What's up in Space
April 21, 2009

AURORA ALERT: Did you sleep through the Northern Lights? Next time get a wake-up call: Spaceweather PHONE.


NEW SUNSPOT: Breaking a string of 25 consecutive spotless days, a new sunspot is forming near the sun's northwestern limb. The magnetic polarity of the spot identifies it as a member of new Solar Cycle 24. Readers, if you have a solar telescope, now is the time to watch sunspot genesis in action.

images: from Pete Lawrence of Selsey, West Sussex, UK; from Jan Timmermans of Valkenswaard, The Netherlands

VENUS & THE MOON: Set your alarm for dawn. Just before sunrise on Wednesday morning, April 22nd, Venus and the crescent Moon will have a spectacular close encounter in the eastern sky. Artist Mark Seibold of Portland, Oregon, is looking forward to the view so much, he couldn't wait to draw it:

In his pastel sketch, both Venus and the Moon are portrayed as crescents. That's not artistic licence. Both worlds have phases and on Wednesday morning both will have a crescent shape. Use binoculars or a small telescope to resolve the tiny arc of Venus.

For sky watchers in western parts of North America, the Moon will completely eclipse Venus. The event begins just after 5 a.m. Pacific Daylight Time and lasts for more than an hour. Local details may be found here.

LYRID METEOR SHOWER: The annual Lyrid meteor shower is underway. "I saw two bright Lyrids last night," reports Marsha Adams of Sedona, Arizona."They seem to start out orange and finish green." She caught this one using a Nikon D200:

Forecasters expect the shower to peak on April 22nd with 10 to 20 meteors per hour over the northern hemisphere. The best time to look is during the dark hours before dawn on Wednesday morning.

Got clouds? No problem. If you can't see the shower, you can listen to it on Space Weather Radio. We are streaming live signals from the Air Force Space Surveillance Radar in Texas. Whenever a meteor passes overhead--ping!--there is an echo. The Lyrids should produce a surge of audio activity.

more images: from Roman Piffl of Bratislava, Slovakia; from Jens Hackmann of Bad Mergentheim, Germany; from Brian Emfinger of Ozark, Arkansas; from Quentin D. of le Havre, Normandy, France

April 2009 Aurora Gallery
[previous Aprils: 2008, 2007, 2006, 2005, 2004, 2003, 2002]

Explore the Sunspot Cycle

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 21, 2009 there were 1049 potentially hazardous asteroids.
April 2009 Earth-asteroid encounters:
Miss Distance
2009 FU30
Apr. 2
8.8 LD
44 m
2004 VC
Apr. 3
51.3 LD
785 m
2002 EB3
Apr. 10
41.3 LD
1.3 km
2003 SG170
Apr. 19
57.7 LD
1.2 km
2009 FJ30
Apr. 24
9.7 LD
130 m
2001 VG5
Apr. 26
58.5 LD
2.1 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 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 and Heliospheric Observatory
  Realtime and archival images of the Sun from SOHO.
  3D views of the sun from NASA's Solar and Terrestrial Relations Observatory
Daily Sunspot Summaries
  from the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
Science Central
  more links...
©2008, -- This site is penned daily by Dr. Tony Phillips.
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