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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 577.4 km/sec
density: 0.5 protons/cm3
explanation | more data
Updated: Today at 2245 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Jun18
24-hr: A0
0505 UT Jun18
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 18 Jun 08
Sunspot 999 poses no threat for strong solar flares. Credit: SOHO/MDI
Sunspot number: 11
What is the sunspot number?
Updated 17 June 2008
Far side of the Sun:
This holographic image reveals one small spot on the far side of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 0 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: 2.9 nT
Bz: 2.0 nT north
explanation | more data
Updated: Today at 2246 UT
Coronal Holes:
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: Hinode X-ray Telescope
NOAA Forecasts
Updated at: 2008 Jun 18 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 Jun 18 2203 UTC
0-24 hr
24-48 hr
25 %
25 %
05 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
25 %
25 %
05 %
05 %
01 %
01 %
What's up in Space
June 18, 2008
AURORA ALERTS: Did you miss the Northern Lights of June 14th? Next time get a wake-up call from Space Weather PHONE.  

MOON ILLUSION: Sometimes you just can't believe your eyes. Tonight may be one of those times. Go outside around sunset, look east, and prepare to be deceived: full story.

photos: from P-M Hedén of Vallentuna, Sweden; from Yuichi Takasaka of Lumby, British Columbia;

NOCTILUCENT CLOUDS: Every night for the past week, northern and central Europeans have witnessed eerie electric-blue noctilucent clouds (NLCs) gliding overhead. This snapshot taken just before daybreak on June 17th comes from Jacob Kuiper of the Netherlands:

Clicking on the image launches a time-lapse movie showing 9 minutes of noctilucent motion. "I have been watching NLCs since 1984 and each time I see their strange glow it gives me a wonderful feeling," says Kuiper. "Today's clouds were accompanied by the sound of the first birds singing just before dawn--it was Nature at its best!"

Summer is the season for noctilucent clouds, so it comes as no surprise that activity is picking up on the eve of the summer solstice (June 20th). Readers, especially you at high latitudes, check the photo gallery for observing tips and be alert for electric-blue!

2008 Noctilucent Cloud Gallery
["Noctilucent Clouds"--the song] [NLC Basics]

SMOKEY PROMINENCE: Where there's smoke, there's fire--except on the sun where there is neither. The fiery appearance of the sun comes not from combustion but rather from nuclear fusion, and without fire there is no smoke.

Or is there? Consider this movie made on June 17th by Yvan Trembley of Villepreux, France:

"I recorded the view through my Coronado SolarMax90," says Trembley. It seems to show a plume of smoke swirling up from the inferno below. In fact, it is a planet-sized wisp of solar hydrogen caught in the grip of an unwinding magnetic field--a solar prominence masquerading as smoke.

The eastern edge of the sun, where Trembley pointed his telescope, has been alive with this kind of activity all week. Got a solar filter? Monitoring is encouraged.

more images: from Mark Seibold of Portland, Oregon; from Didier Favre of Brétigny sur Orges, France; from Cai-Uso Wohler of Bispingen, Germany; from Stephen Ames of Hodgenville, Kentucky; from Emiel Veldhuis of Zwolle, the Netherlands; from Steve Irvine of Big Bay, Ontario, Canada

May 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 June 18, 2008 there were 957 potentially hazardous asteroids.
June-July 2008 Earth-asteroid encounters:
Miss Distance
2008 KO
June 1
4.4 LD
60 m
2008 KT
June 3
3.3 LD
9 m
2008 LB
June 9
3.3 LD
26 m
2008 LG2
June 13
9.2 LD
36 m
2008 LC
June 17
9.8 LD
55 m
2008 KN11
June 22
9.0 LD
110 m
2000 AD205
June 26
54 LD
800 m
1999 VU
June 29
65 LD
1.6 km
2008 BT18
July 14
5.9 LD
1.0 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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