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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 574.7 km/sec
density: 0.5 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: A0
2005 UT Apr13
24-hr: A0
2005 UT Apr13
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 13 Apr 08
A new sunspot may be emerging at the location of the question mark. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 12 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: 3.2 nT
Bz: 0.7 nT north
explanation | more data
Updated: Today at 2247 UT
Coronal Holes:
The entire Earth-facing side of the sun is a poorly-organized coronal hole. This sometimes happens during solar minimum when the sun's magnetic field relaxes, allowing solar wind to escape from wide expanses of the sun's atmosphere. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2008 Apr 13 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 13 2203 UTC
0-24 hr
24-48 hr
15 %
15 %
05 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
25 %
25 %
15 %
15 %
01 %
01 %
What's up in Space
April 13, 2008
Where's Saturn? Is that a UFO--or the ISS? What's the name of that star? Get the answers from mySKY--a fun new astronomy helper from Meade.   mySKY

SPACE STATION FLYBYS: Sky watchers in North America might notice a bright light streaking across the evening sky this weekend. It's the International Space Station. The busily expanding station is now as luminous as Venus even when it doesn't fly directly overhead; some observers report seeing it through clouds. US and Canadian readers, find out when to look using our new Simple Satellite Tracker.

NEW CYCLE SPOT: Solar Cycle 24 began on Jan. 4th with the appearance of a magnetically-reversed, high-latitude sunspot. After that, more than three months passed without another new-cycle spot--until this weekend. The second sunspot of Solar Cycle 24 has finally materialized:

The images shown above were obtained on April 13th by the Solar and Heliospheric Observatory (SOHO). The sunspot is a tiny-looking dark speck in the white light image. Shades of gray in the magnetogram trace the sunspot's underlying magnetic polarity; the N-S pattern signals its membership in Solar Cycle 24.

This is not a large or impressive sunspot, but it does confirm that Solar Cycle 24 has truly begun. In the months ahead, we can expect more new cycle spots as solar activity emerges from its current low ebb and surges toward the next Solar Maximum expected in 2011-12. Stay tuned!

more images: from Matt Wastell of Brisbane, Australia; from Pete Lawrence of Selsey, West Sussex, UK; from Stephen Ames of Hodgenville, KY; from Cai-Uso Wohler of Bispingen, Germany; from Jan Timmermans of Valkenswaard, The Netherlands; from Peter Paice of Belfast, Northern Ireland;

SOLAR TRANSIT: Good thing TIE fighters have heat shields. Oh wait, it's just the International Space Station (ISS):

Click to view the movie

John Stetson photographed the ISS transiting the sun over Falmouth, Maine, on April 8th. It was a split-second affair: "The transit movie lasts about 11 seconds," he says, "but the actual transit lasted less than one second."

The TIE-fighter shape of the silhouette traces the space station's impressively long and recently unfurled double solar arrays. No heat shield was required because, although the station appears to be skimming the surface of the sun, it is really only 200 miles above Earth. Even so, it is one hot picture!

UPDATED: 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 13, 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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