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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 498.7 km/sec
density: 1.3 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Apr20
24-hr: A0
1410 UT Apr20
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 20 Apr 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 13
What is the sunspot number?
Updated 19 Apr 2008
Far side of the Sun:
This holographic image reveals no large sunspots on the farside 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: 3.4 nT
Bz: 3.1 nT north
explanation | more data
Updated: Today at 2247 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on or about April 25th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2008 Apr 20 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 20 2203 UTC
0-24 hr
24-48 hr
10 %
20 %
05 %
10 %
01 %
05 %
High latitudes
0-24 hr
24-48 hr
10 %
25 %
05 %
10 %
01 %
05 %
What's up in Space
April 20, 2008
FLYBY ALERT! Would you like a phone call when the International Space Station (ISS) is about to fly over your back yard? Sign up for Space Weather PHONE.  

PROM ALERT: The limb of the sun is bristling with activity today. Several large prominences have caught the attention of observers with solar telescopes. Click to view images from Pete Lawrence of Selsey, West Sussex, UK; from Didier Favre of Brétigny sur Orge, France; from Jyoti S Mahindru of Oakleigh South, Victoria, Australia.

LYRID METEORS: Earth is entering a stream of debris from Comet Thatcher, the source of the annual Lyrid meteor shower. Unfortunately this year's display will be curtailed by bright moonlight; forecasters expect no more than 5 to 10 meteors per hour when the shower peaks on April 21st and 22nd. The only hope for more is a Lyrid outburst, which sometimes happens when Earth passes through a dense clump of debris. The last such outburst in 1982 produced more than 90 Lyrids per hour: full story.

LUNA AND THE BELT OF VENUS: Last night when the full Moon rose in the east, it passed through a luminous pink band known as the Belt of Venus. "What a wonderous moonrise!" says photographer P-M Hedén who sends this picture of his children watching from Vallentuna, Sweden:

Photo details: Canon Digital Rebel XT, Sigma 20mm lens

What is the Belt of Venus? It divides night from day: diagram. Below the belt lies the shadow of Earth, which rises in the east at sunset to darken the sky and bring out the stars. Above the belt lingers the fading blue of daytime. The day-night border is colored pink by sunset rays from the opposite side of the sky--a beautiful sight.

The Belt of Venus is visible from all parts of Earth on every night (look east when the sun is going down), but the full Moon passes through it only once a month. Says Hedén, "my children and I thoroughly enjoyed the show."

more images: from M. Ouellette, J. Fairfull, and John Stetson of South Portland, Maine

BEAUTY AND THE BEAST: On March 19th, the summit of Hawaii's Kilauea volcano exploded for the first time since 1924. The blast was first thought to be an earthquake, but volcanologists quickly realized what had happened: gases bottled up beneath a vent named "Halema`uma`u" had burst forth, spewing debris over an area of 75 acres.

Last week, on April 14th, "I was watching sulfur dioxide emissions from Halema`uma`u, which is still fuming," reports photographer Mila Zinkova. "Suddenly I noticed a rainbow, which gently touched the crater rim."

"Beauty and the Beast, I thought. But is the volcano really a beast?" she asks. "Yes, indeed. A few days ago thousands of people fled the Hawaii Volcanoes National Park and nearby villages when sulfur dioxide levels become deadly. On the other hand, Hawaiian islands were created by volcanoes. Even now Pu`u `O`o (an active vent on Kilauea's eastern flank) sends lava to the ocean creating new land and beautiful new beaches."

more images: from Mike Sessions of Hawaii, the Big Island

webcams: Halema`uma`u, Pu`u `O`o

April 2008 Aurora Gallery
[Aurora Alerts] [Night-sky Cameras]

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 20, 2008 there were 946 potentially hazardous asteroids.
April 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
2001 DQ8
Apr. 30
74 LD
1.1 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 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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