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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 501.6 km/sec
density: 1.2 protons/cm3
explanation | more data
Updated: Today at 2221 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Jun17
24-hr: A0
2245 UT Jun17
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 17 June 07
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 16 June 2007
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= 1 quiet
24-hr max: Kp= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Updated: 2007 Jun 17 2105 UT
Interplanetary Mag. Field
Btotal: 4.9 nT
Bz: 0.6 nT north
explanation | more data
Updated:Today at 2246 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on or about June 21st. Credit: SOHO Extreme Ultraviolet Telescope
NOAA Forecasts
Updated at: 2007 Jun 17 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: 2007 Jun 17 2203 UTC
0-24 hr
24-48 hr
15 %
25 %
10 %
15 %
01 %
05 %
High latitudes
0-24 hr
24-48 hr
20 %
30 %
15 %
20 %
05 %
10 %
What's up in Space
June 17, 2007
Today is Father's Day. Skip the tie and give him the stars: SpaceWeather PHONE.

NLC ALERT: Reports are pouring in of NLCs over Europe tonight, June 17th. Tomasz Adam sends this picture from Staszow, Poland. Soon, night will fall over North America and NLCs may appear there, too. Favored viewing sites include Alaska, Canada and northern-tier US states--the same places auroras are often seen. Click here for observing tips and photos.

SUNSET PLANETS: When the sun sets tonight, go outside and look west. Saturn, Venus and the slender crescent Moon are arranged in a beautiful diagonal line. Scan the trio with a backyard telescope to see mountains and craters, breathtaking rings, and a curiously cloudy crescent. [sky map]

DAYLIGHT ECLIPSE OF VENUS: European and Middle Eastern sky watchers should be alert on June 18th for a mid-afternoon eclipse of Venus by the crescent Moon. Venus is bright enough to see in broad daylight, and having the Moon nearby makes it easy to find. Click here for time tables and a visibility map.

NIGHT-SHINING CLOUDS: For future reference, this is what we mean by electric blue:

Photo details: Nikon D70, ISO 200, 5 seconds.

Jan Koeman of the Netherlands took the picture on Friday night, June 15th, when a vivid display of noctilucent clouds swept across Europe, descending as far south as France and Hungary: gallery.

This latest display marks the second time since space shuttle Atlantis launched on June 8th that Europe has witnessed bright NLCs. Coincidence? Studies show that shuttle launches can promote noctilucent clouds. Exhaust from the main engines of NASA's space shuttle is about 97 percent water vapor, and this vapor can travel from Florida to the Arctic in little more than a day. Once there, it forms ice crystals for NLCs at the edge of space. The space shuttle cannot be wholly responsible for noctilucent clouds, which were first sighted in the 19th century long before space travel, but it may be a contributing factor to these modern displays.

2007 Noctilucent Photo Gallery
[Listen!] [Night-sky Cameras]

IRANIAN MYSTERY CLOUD: On June 15th, sky watchers around Iran witnessed a strange and luminous cloud in the night sky. "I have never experienced a similar phenomena," reports veteran astronomer Babak A. Tafreshi of Tehran. Observing alongside two other astronomers, Oshin Zakarian and Pouria Nazemi, he took this picture:

Photo details: Canon 350D, 28mm, ISO 800, f4, 35s.

"The object started out patchy, shapeless and dim; it quickly brightened and formed a blue-tinted cone with a nose of magnitude -2 or -3," he says. The cloud raced across the sky "moving about 20 degrees per minute." More images: #1, #2, #3, #4, #5, #6.

"It was shining blue and moving fast," agrees Amir Hossein Abolfath, another witness from Tehran, who snapped this picture. "Twenty minutes after I saw it, my friend Asghar Kabiri saw the same cloud 900 km away from Tehran in Sa'adat shahr."

More images: from Muhammad Saber Karimi of Kermanshah, Iran; from Hossein Haeri Ardekani of Ardekan, Yazd, Iran.

Mystery solved? The following explanation is probably correct, but uncertain because of the classified nature of the implicated rocket launch:

On June 15th at 11:12 am EDT, an Atlas V rocket launched from Cape Canaveral; its payload was a pair of National Reconnaissance Office ocean surveillance satellites. After the satellites were deployed--into the wrong orbit, according to media reports--the rocket's malfunctioning Centaur upper stage vented excess fuel, producing the Iranian cloud. The dumping of excess fuel is standard practice for Centaur-boosted launches, and this event is probably unrelated to the Centaur's reported malfunction.

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 June 17, 2007 there were 869 potentially hazardous asteroids.
June-July 2007 Earth-asteroid encounters:
Miss Distance
2005 AD13
June 18
33 LD
1.2 km
2007 FV42
July 2
53 LD
1.2 km
2007 DT103
July 29
9.3 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 Environment 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...
©2007, -- This site is penned daily by Dr. Tony Phillips.
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