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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 420.9 km/sec
density: 0.7 protons/cm3
explanation | more data
Updated: Today at 2245 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Apr29
24-hr: A0
1405 UT Apr29
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 29 Apr 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 27 Apr 2008
Far side of the Sun:
This holographic image reveals no sunspots on the farside of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 3
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 2.1 nT
Bz: 0.1 nT south
explanation | more data
Updated: Today at 2246 UT
Coronal Holes:
A minor solar wind stream flowing from this small coronal hole could reach Earth on or about April 30th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2008 Apr 29 2203 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: 2008 Apr 29 2203 UTC
0-24 hr
24-48 hr
30 %
30 %
10 %
10 %
05 %
05 %
High latitudes
0-24 hr
24-48 hr
45 %
50 %
15 %
15 %
05 %
05 %
What's up in Space
April 29, 2008
MOTHER'S DAY: Give your mom a truly heavenly gift on May 11th--a subscription to Space Weather PHONE!  

CME UPDATE: Geomagnetic activity remains low. A coronal mass ejection hurled into space by the April 26th "no-sunspot" solar flare has either missed Earth or its impact was too weak to register on solar wind sensors in Earth orbit. Auroras tonight appear unlikely.

STORMS ON SATURN: Amateur astronomers photographing Saturn this week have found something unexpected. "I was taking routine images of Saturn this evening, hoping to see some interesting features," says Ian Sharp of Ham, UK. "I was thrilled to see I had captured two storms" denoted by arrows in the picture below:

They're little more than smudges in this view through a backyard telescope, but each one is a continent-sized tempest with wind speeds as high as 1000 mph. Saturn's storms are white because their cloudtops are filled with ammonia ice crystals--think of the ice halos!--and they sometimes crackle with powerful lightning that radio receivers onboard the Cassini spacecraft have recorded on many occasions: listen.

These storms appear to be intensifying and are now easy targets for backyard telescopes equipped with CCD cameras. Monitoring is encouraged: sky map.

more images: from G√ľnther Strauch of Borken, NRW, Germany; from Roman Breisch of Erdweg, Bavaria, Germany;

IRIDIUM FLARES, ALL NIGHT LONG: Anyone who's ever seen an Iridium satellite flaring in the night sky knows what it must be like to witness a supernova. Sudden. Breath-taking. Unforgettable.

At the South Pole, the unforgettable happens 160 times a day. NSF research engineer J. Dana Hrubes sends this report from the Amundsen-Scott South Pole Station where all six orbital planes of the polar-orbiting Iridium satellites cross: "The sun has set here for 6 months and we get Iridium flares every 9 minutes and 8 seconds for 4-5 days at a time." Indeed, such a "flare session" is underway now.

This April 28th self-portrait shows Hrubes with a flare in the background near the Southern Cross. The brilliant flash of light occurred when sunlight glinted off one of the satellite's flat surfaces. "I took this picture and three others using my Canon Rebel XTI 400D," says Hrubes. "The brightest magnitude -8 flares occur every 9 min for an entire day! We routinely use the Iridium satellites for communication from the Pole."

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. [comment]
On April 29, 2008 there were 946 potentially hazardous asteroids.
April-May 2008 Earth-asteroid encounters:
Miss Distance
2008 FH5
Apr. 2
7.6 LD
17 m
2001 QO142
Apr. 6
34 LD
685 m
2008 GF1
Apr. 7
0.8 LD
10 m
2005 BE2
Apr. 10
62 LD
1.0 km
2005 NB7
Apr. 17
16 LD
705 m
2008 FU6
Apr. 22
62 LD
1.4 km
2005 TB
Apr. 28
47 LD
1.3 km
2008 HJ
Apr. 29
2.8 LD
34 m
2001 DQ8
Apr. 30
74 LD
1.1 km
2008 HG
May 5
17 LD
90 m
2008 DE
May 9
17 LD
550 m
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 bureau for real-time monitoring of solar and geophysical events, research in solar-terrestrial physics, and forecasting solar and geophysical disturbances.
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.
Daily Sunspot Summaries
  From the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
  more links...
©2008, -- This site is penned daily by Dr. Tony Phillips.
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