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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 381.7 km/sec
density: 7.4 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Aug03
24-hr: A0
0020 UT Aug03
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 28 July 09
The sun is blank--no sunspots. Credit: SOHO/MDI

Note: Why is the 'daily sun' several days old? Solar and Heliospheric Observatory (SOHO) is having a minor problem. SOHO's white light solar telescope is temporarily offline while new commands and data tables are uploaded to the spacecraft. Normal operations are expected to resume in a few days.
Sunspot number: 0
What is the sunspot number?
Updated 02 Aug 2009

Spotless Days
Current Stretch: 23 days
2009 total: 165 days (77%)
Since 2004: 676 days
Typical Solar Min: 485 days
explanation | more info
Updated 02 Aug 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= 2 quiet
24-hr max: Kp= 3
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 1.8 nT
Bz: 0.7 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole could reach Earth on or about Aug. 6th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Aug 03 2201 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: 2009 Aug 03 2201 UTC
0-24 hr
24-48 hr
05 %
20 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
10 %
25 %
01 %
05 %
01 %
01 %
What's up in Space
August 3, 2009

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


EXTRA MOON OF JUPITER: Seen through a backyard telescope, Jupiter usually has four bright moons. Tonight the number is five. Jupiter is having a close encounter with 6th-magnitude star 45 Cap, temporarily increasing the "moon count" by one. Observers in Europe, Africa, the Middle East and Brazil can watch Jupiter pass directly in front of 45 Cap. The eclipse occurs roughly from 22:53 Universal Time on August 3rd to 1:00 UT August 4th. [full story] [sky map]

SWIRLING DEBRIS ON JUPITER: The impact cloud on Jupiter continues to expand and evolve. On August 1st and 2nd, worldwide observers noted that it had transformed from a concentrated, cindery-black spot to an Earth-sized paling swirl. South is up in this image from Anthony Wesley of Murrumbateman, Australia:

"Polar winds seem to be carrying the main body of the cloud westward (to the right in the photo)," Wesley says. "Also, a small stream of dark material is being pulled down and in the opposite direction--perhaps around a cyclone or some other localised weather feature?" (Bonus: The moon in the foreground casting its shadow on Jupiter's cloudtops is Io.)

Researchers are scrambling to study the cloud before it fully disperses. Light reflected from the debris may hold clues to the nature of the mystery-impactor. "If the cloud's spectra contain signs of water, that would suggest an icy comet. Otherwise, it's probably a rocky or metallic asteroid," says JPL planetary scientist Glenn Orton. Several teams of professional astronomers are working to obtain the data--stay tuned for updates.

Meanwhile, amateur astronomers can monitor the cloud as it shifts and swirls near Jupiter's System II longitude 210°. For the predicted times when it will cross the planet's central meridian, add 2 hours and 6 minutes to Sky and Telescope's predicted transit times for Jupiter's Great Red Spot. [sky map]

more images: from Raffaello Lena of Rome, Italy; from Glenn Jolly of Gilbert, Arizona, USA; from Wah! of Hong Kong; from William Rison of Newburg, Maryland; from Joel Warren of Amarillo, Texas; from David Kolb of Lawrence, Kansas; from Alphajuno of League City, Texas; from Mariano Ribas of Buenos Aires, Argentina; from Giancarlo Ubaldo Nappi of Belo Horizonte, Minas Gerais, Brazil

FAUX-VOLCANIC SUNSETS: Almost two full months after Russia's Sarychev volcano erupted, peppering the stratosphere with ash and sulfur dioxide, Doug Zubenel is still seeing volcanic sunsets over Kansas. Is he having a flashback? It certainly seems real:

"I took this picture last night," says Zubenel. "The sky had the telltale lavendar color and ray structure characteristic of a volcanic sunset."

However, Sarychev may not be to blame. "A more likely cause for these colors is wildfires burning across the western US," points out Zubenel. There are 28 major fires in progress right now. Strong updrafts can pull the fires' fine, smokey aerosols into the lower stratosphere, where their effect on the sunset mimicks that of a volcano. As wildfire season unfolds--it is most intense during late summer and fall when ground vegetation dies and becomes kindling--these "faux-volcanic sunsets" could increase in frequency and intensity. Submit your images here.

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

July 2009 Aurora Gallery
[previous Julys: 2008, 2007, 2006, 2005, 2004, 2003]

July 22nd Eclipse Gallery
[previous eclipses: Jan 26, 2009; Aug. 1, 2008; Mar. 19, 2007]

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 August 3, 2009 there were 1067 potentially hazardous asteroids.
August 2009 Earth-asteroid encounters:
Miss Distance
2009 MC9
Aug. 7
70.3 LD
1.2 km
2009 OF
Aug. 8
15.4 LD
220 m
2007 RQ17
Aug. 9
8.4 LD
130 m
2000 LC16
Aug. 17
75.6 LD
2.0 km
2006 SV19
Aug. 21
59.2 LD
1.3 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 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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