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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 380.0 km/sec
density: 16.2 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Aug05
24-hr: A0
1350 UT Aug05
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 04 Aug 2009

Spotless Days
Current Stretch: 25 days
2009 total: 167 days (77%)
Since 2004: 678 days
Typical Solar Min: 485 days
explanation | more info
Updated 04 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= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 10.0 nT
Bz: 9.9 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. 7th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Aug 05 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 05 2201 UTC
0-24 hr
24-48 hr
20 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
25 %
10 %
05 %
01 %
01 %
01 %
What's up in Space
August 5, 2009

KILLER PERSEID APP: You can now experience the Perseid meteor shower on your iPhone. It's cloud-proof! Learn more and give it a try.


FULL MOON AND JUPITER: Tonight, when the sun sets, go outside and look southeast. The full Moon is having a close encounter with Jupiter. The two are so bright, you won't even need a sky map to find them. Moon shots: from Anthony Ayiomamitis of Athens, Greece.

POSSIBLE PERSEID OUTBURST: This year's Perseid meteor shower could be even better than usual. "A filament of comet dust has drifted across Earth's path and when Earth passes through it, sometime between 0800 and 0900 UT (1 - 2 am PDT) on August 12th, the Perseid meteor rate could surge to twice its normal value," says Bill Cooke of NASA's Meteoroid Environment Office. The following profile is based on the debris stream models of veteran forecasters Jeremie Vaubaillon and Mikhail Maslov:

The filament was shed by Perseid parent comet Swift-Tuttle in the year 1610, and this is one of Earth's first encounters with it. "In addition," notes Cooke, "the main Perseid debris stream, which we run into every year, may be denser than normal due to a gravitational enhancement by Saturn. The total combination of these effects could result in as many as 200 meteors per hour (ZHR)."

Bright moonlight will overwhelm the outburst's fainter Perseids, but even a fraction of 200 is a good show. Science@NASA's "The Perseids are Coming" offers observing tips and sky maps.

SWIRLING DEBRIS ON JUPITER: The "Wesley 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 just-updated Aug. 3rd image from the cloud's discoverer, Anthony Wesley of Murrumbateman, Australia:

"Polar winds seem to be carrying the main body of the cloud westward (to the right in the photo)," says Wesley. "Also, a small stream of dark material is being pulled down and in the opposite direction--perhaps around a cyclone or some other localized weather feature?"

Researchers are scrambling to study the cloud before it 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.

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

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

July 2009 Aurora Gallery
[previous Julys: 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 August 5, 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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