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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 446.1 km/sec
density: 1.9 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: A0
1805 UT Jul25
24-hr: A0
1805 UT Jul25
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 25 July 09
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 24 July 2009

Spotless Days
Current Stretch: 14 days
2009 total: 156 days (76%)
Since 2004: 667 days
Typical Solar Min: 485 days
explanation | more info
Updated 24 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= 2 quiet
24-hr max: Kp= 3
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 2.6 nT
Bz: 1.1 nT north
explanation | more data
Updated: Today at 2346 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 25 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 Jul 25 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 25, 2009

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


WHAT'S FOLLOWING THE ISS? A number of readers who went outdoors after dark on July 24th to see the International Space Station say they also saw an object following (or even passing) the station. The follower was probably the Progress 34, a Russian supply ship which launched earlier in the day from the Baikonur Cosmodrome in Kazakhstan. Check the Simple Satellite Tracker for ISS flyby times and get two spaceships for the price of one.

HUBBLE SEES JUPITER IMPACT: The Jupiter impact scar discovered by amateur astronomer Anthony Wesley on July 19th has been photographed by the Hubble Space Telescope:

"This July 23rd Hubble photo shows a lumpiness to the debris plume caused by turbulence in Jupiter's atmosphere," says Amy Simon-Miller of NASA's Goddard Space Flight Center. Based on the appearance of the impact zone, she estimates that the diameter of the impacting object was several hundred meters--i.e., several football fields wide. The force of the explosion was likely thousands of times greater than the Tunguska impact of 1908.

The impact scar remains an easy target for mid-sized backyard telescopes, and amateur astronomers can contribute to its study by monitoring Jupiter in the nights ahead: sky map. The spot is located 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.

AURORAS OVER NEBRASKA: "This past Wednesday, I spent the night at at the Nebraska Star Party in Valentine, Nebraska," says amateur astronomer Howard Edin. "Just after midnight I noticed a pale arc of clouds in the north; after staring for a while I realized they were not clouds," A 30-second exposure he made using his Canon 40D revealed the nature of the phenomenon:

"It was the aurora borealis," he says.

Although he didn't know it at the time, a solar wind stream had just hit Earth's magnetic field, sparking bright auroras over Canada and several northern-tier US states. Nebraska was at the outer limit of the display, so the auroral colors were too dim for human vision, but a digital camera picked them up quite nicely.

Memo to astrophotographers: Auroras can be a great deep-sky target. Sign up for geomagnetic storm alerts, and you'll always know when to open the shutter.

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

2009 Noctilucent Photo Gallery
[previous years: 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 July 25, 2009 there were 1067 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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