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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 325.4 km/sec
density: 3.7 protons/cm3
explanation | more data
Updated: Today at 2333 UT
X-ray Solar Flares
6-hr max: A2
2150 UT Apr30
24-hr: A6
1120 UT Apr30
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 30 Apr 09
Sunspot 1016 is a member of old Solar Cycle 23. Credit: SOHO/MDI
Sunspot number: 15
What is the sunspot number?
Updated 29 Apr 2009

NEW: Spotless Days
Current Stretch: 0 days
2009 total: 104 days (88%)
Since 2004: 615 days
Typical Solar Min: 485 days
explanation | more info
Updated 29 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= 0 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: 3.1 nT
Bz: 1.4 nT north
explanation | more data
Updated: Today at 2334 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on or about May 6th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Apr 30 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 30 2201 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
What's up in Space
April 30, 2009

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


SUNSPOT 1016: A ring-shaped sunspot numbered 1016 has emerged near the sun's equator. Its magnetic polarity identifies it as a member of old Solar Cycle 23. Until these old cycle sunspots go away, the next solar cycle will remain in abeyance. Readers with solar telescopes should point their optics here.

SPACE STATION FLARE: Just before sunrise on April 28th, Nicolas Biver watched the International Space Station (ISS) cross the starry sky above Versailles, France. Suddenly "the station flared," he says. "It was brighter than Venus!" A digital video taken through his 16-inch Dobsonian telescope reveals what happened:

"Sunlight glinted off some of the station's solar panels," says Biver. "The reflection was intense."

Under construction for more than ten years, the ISS has only recently received its full complement of solar arrays. Space shuttle astronauts added a final set of "wings" in March 2009, boosting the surface area of the photovoltaic system to a whopping 16,000 square feet. With so much sun-collecting area, occasional glints are inevitable--and very bright.

Check the Simple Satellite Tracker to find out when the ISS might be flaring over your home town.

ZENITH HALO: "April 26th is the day here in Guam (13.5o N) that the sun passes directly overhead at local noon," says Tom Wittman of Andersen Air Force Base. "When the time came, I stepped outside and was treated to a beautiful ice halo." This photo, he says, was taken at the exact moment the sun reached zenith:

Zenith suns are not required for ice halos, but they make good ones: The Guam display is probably a combination of a 22o halo and a circumscribed halo, two halos that overlap for maximum luminosity when the sun is directly overhead.

"Later in the summer, as the sun returns south from the Tropic of Cancer, the islanders here in Guam will be treated to another zenith sun," adds Wittman. "I wonder what optical extra may make an appearance then?" Stay tuned.

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 30, 2009 there were 1053 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 HF21
Apr. 21
7.4 LD
27 m
2009 HJ21
Apr. 23
1.3 LD
14 m
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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