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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 532.3 km/sec
density: 2.2 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Jul24
24-hr: A0
2340 UT Jul24
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 24 July 09
A small sunspot is developing inside the circled region. Its magnetic polarity identifies it as a member of old Solar Cycle 23. Credit: SOHO/MDI

more images: from Pavol Rapavy of Observatory Rimavska Sobota; from Mark Townley of Brierley Hill, West Midlands, UK; from Richard Best of Lewes, East Sussex, England
Sunspot number: 0
What is the sunspot number?
Updated 23 July 2009

Spotless Days
Current Stretch: 13 days
2009 total: 155 days (76%)
Since 2004: 666 days
Typical Solar Min: 485 days
explanation | more info
Updated 23 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= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 2.5 nT
Bz: 0.6 nT south
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 24 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 24 2201 UTC
0-24 hr
24-48 hr
05 %
10 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
05 %
15 %
01 %
05 %
01 %
01 %
What's up in Space
July 24, 2009

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


JUPITER UPDATE: Five days after it was discovered, the dark mark in Jupiter's cloudtops where an asteroid or comet hit the giant planet is still easy to see through backyard telescopes. Browse these links for recent images: #1, #2, #3, #4, #5, #6.

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.

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

NOCTILUCENT CLOUDS OVER OREGON: "Last night, July 23rd, we stepped outside to watch an ISS flyover, but that performance was outstaged by one of the most spectacular NLC displays I've ever witnessed!" reports Paul Wagner of Portland, Oregon. The electric-blue clouds were almost as bright as some of the porch lights in his neighborhood:

Andrew Robb saw the same display: "They came through like a storm. These were the brightest noctilucent clouds I've seen yet over the Portland area, and they really had a nice variety of forms. What a sight!"

This is the second time in July that bright noctilucent clouds have descended from their usual arctic habitat to the continental United States. Sightings have been made in Colorado, Utah, Washington, Oregon, Nebraska, Nevada and many other states where the night sky does not usually turn electric-blue. No one knows why the mysterious clouds are spreading south, but they are; observers at all latitudes should be alert for NLCs.

UPDATED: 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 24, 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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