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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 324.7 km/sec
density: 3.3 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: B4
2210 UT Jul04
24-hr: B7
0435 UT Jul04
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 04 July 09
New-cycle sunspot 1024 is growing rapidly and crackling with B-class solar flares. Credit: SOHO/MDI
Sunspot number: 17
What is the sunspot number?
Updated 03 July 2009

Spotless Days
Current Stretch: 0 days
2009 total: 142 days (77%)
Since 2004: 653 days
Typical Solar Min: 485 days
explanation | more info
Updated 03 July 2009

Far side of the Sun:
This holographic image reveals no sunspots on the far side 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
Interplanetary Mag. Field
Btotal: 4.5 nT
Bz: 0.4 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes:
There are no large coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Jul 04 2201 UTC
0-24 hr
24-48 hr
05 %
05 %
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: 2009 Jul 04 2201 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
What's up in Space
July 4, 2009

AURORA ALERT: Did you sleep through the Northern Lights? Next time get a wake-up call: Spaceweather PHONE.


SPACE STATION MARATHON: The International Space Station (ISS) is about to make a remarkable series of flybys over the United States. Beginning this 4th of July weekend, the station will appear once, twice, and sometimes three times a day for many days in a row. Check the Simple Satellite Tracker for flyby times.

SUNSPOT ALERT: The most active sunspot of the year so far is emerging in the sun's southern hemisphere: movie. Sunspot 1024 has at least a dozen individual dark cores and it is crackling with B-class solar flares. This morning, amateur astronomer David Tyler caught one of the flares in action from his backyard solar observatory in England:

The magnetic polarity of sunspot 1024 identifies it as a member of new Solar Cycle 24. Its rapid emergence on July 3rd and 4th continues the recent (few-month) trend of intensifying new-cycle activity. This sunspot is the best offering yet from the young solar cycle. Monitoring is encouraged.

more images: from Pete Lawrence of Selsey, West Sussex, UK; from Mark Townley of Brierley Hill, West Midlands, UK; from Cesare Guaita of Tradate, Italy; from Jan Timmermans of Valkenswaard, The Netherlands; from Emiel Veldhuis of Zwolle, the Netherlands; from SOHO in orbit; from Peter Desypris on the Island of Syros, Greece; from Bruno Nolf of Otegem, Belgium;

SWIRLING SULFUR DIOXIDE: A massive plume of ash and sulfur dioxide expelled by Russia's Sarychev Peak volcano on June 12th is swirling through the stratosphere over the northern hemisphere. Europe's MetOpA satellite is monitoring the SO2, colored red in this 5-day animation spanning June 25th through 30th:

Sarychev's emissions are causing some beautiful sunsets. Here's what to look for: When the sun goes down, delicate ripples of white appear over the western horizon. The ripples are volcanic aerosols--a mixture of ash and sulfur compounds. Then, as twilight deepens, the sky turns a lovely shade of "volcanic lavender." Lavender is what you get when you mix blue light scattered by fine aerosols with ordinary red sunset rays.

Is a plume passing over your area tonight? Keep an eye on the western sky for Sarychev sunsets.

2009 Sarychev Sunset Gallery
[See also: 2008 Kasatochi Sunset Photo Gallery]

GEO-FLARE: One night last month, Miroslav Grnja of Bratislava, Slovakia, opened the shutter of his camera (a Canon 400D) and settled back to watch the stars go by. He was looking forward to recording a nice set of star trails--but one of stars refused to move:

"At first I thought I had a hot pixel in my camera," says Grnja. "Upon closer inspection, however, I realized I had photographed a geostationary satellite." Geostationary satellites (geosats) remain fixed above one point on Earth's surface, so they do not move with the stars.

Usually, geosats are too dim to show up in star-trail photos. This one was different. "It flared," says Grnja who made a movie of the flash by stiching together consecutive 90-second exposures. "The satellite brightened to magnitude +2 as sunlight glinted from one of its flat surfaces--perhaps an antenna or a solar panel."

Which geosat was it? Grnja has narrowed the possibilities to two: "E-BIRD (27948 2003-043-A) and Intelsat 802 (26038 1997-031-A) were both in that part of the sky during my photo-shoot." Satellite observers may wish to keep an eye on these birds for future outbursts.

UPDATED: 2009 Noctilucent Photo Gallery
[previous years: 2008, 2007, 2006, 2005, 2004, 2003]

Explore the Sunspot Cycle

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 July 4, 2009 there were 1065 potentially hazardous asteroids.
July 2009 Earth-asteroid encounters:
Miss Distance
2009 MM8
July 13
11.4 LD
53 m
2008 NP3
July 18
11.8 LD
87 m
2006 TU7
July 20
14.2 LD
175 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 space weather bureau
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.
  3D views of the sun from NASA's Solar and Terrestrial Relations Observatory
Daily Sunspot Summaries
  from the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
Science Central
  more links...
©2008, -- This site is penned daily by Dr. Tony Phillips.
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