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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 344.2 km/sec
density: 0.0 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: B2
2205 UT Sep04
24-hr: B3
1600 UT Sep04
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 04 Sep 10
Sunspot 1105 is growing rapidly, but does not yet pose a threat for strong solar flares.
Resolutions: 4096, 1024, 512
Sunspot number: 54
What is the sunspot number?
Updated 03 Sep 2010

Spotless Days
Current Stretch: 0 days
2010 total: 39 days (16%)
2009 total: 260 days (71%)
Since 2004: 807 days
Typical Solar Min: 486 days
explanation | more info
Updated 03 Sep 2010

The Radio Sun
10.7 cm flux: 77 sfu
explanation | more data
Updated 03 Sep 2010

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2
explanation | more data
Interplanetary Mag. Field
Btotal: 2.3 nT
Bz: 0.9 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal holes: 04 Sep 10
A solar wind stream flowing from the indicated coronal hole could reach Earth on Sept. 5th or 6th. Credit: SDO/AIA
NOAA Forecasts
Updated at: 2010 Sep 04 2201 UTC
0-24 hr
24-48 hr
15 %
15 %
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: 2010 Sep 04 2201 UTC
0-24 hr
24-48 hr
40 %
40 %
10 %
10 %
05 %
05 %
High latitudes
0-24 hr
24-48 hr
50 %
50 %
20 %
20 %
10 %
10 %
What's up in Space
September 4, 2010

iPHONE VS ANDROID! Actually, it doesn't matter which phone you carry. Our cool, new app turns both smartphones into field-tested satellite trackers. Learn more.


NASA MISSION TO TOUCH THE SUN: NASA's daring plan to visit the sun took a giant leap forward today with the selection of five key science investigations for the Solar Probe+ spacecraft. Get the full story from Science@NASA.

LIMB EXPLOSION: Today around 1600 UT, a magnetic filament erupted and hurled a massive coronal mass ejection (CME) off the sun's northwestern limb. Click on the image to view a close-up movie of the blast from NASA's Solar Dynamics Observatory:

Another movie from the Solar and Heliospheric Observatory (SOHO) shows the CME billowing into space. The cloud is not heading toward Earth, and no geomagnetic storms are expected from this blast.

However, space weather could be in the offing for a different reason. A solar wind stream is heading for Earth and it could spark auroras when it arrives on Sept. 5th or 6th. NOAA forecasters estimate a 50% chance of geomagnetic activity at high latitudes.

VIRTUAL REALITY PARHELIC CIRCLE: A parhelic circle is an unforgettable sight. Thin and pale, it circles the zenith in a majestic arc, always keeping the same distance above the horizon. "I've been looking for a parhelic circle for more than 13 years," says photographer Laurent Laveder of Pluguffan, France. "Yesterday I finally saw one." He rushed for his camera and quickly snapped enough pictures to assemble a complete 360o zenith-to-horizon composite view of the phenomenon. Click on the image below to experience the VR parhelic circle:

Parhelic circles are caused by sunlight reflecting from the vertical faces of ice crystals--millions of them floating in thin cirrus clouds spread almost evenly across the wide blue sky. As Les Cowley notes in his authoritative web page on the subject, "the parhelic circle appears simple yet more ray paths contribute to it than in any other halo. Some are very intricate."

A striking aspect of the parhelic circle is its dual personality. At the same time it appears both circular and straight. "These two pictures (1, 2) illustrate the effect," says Laveder. More images may be found here.

August 2010 Northern Lights Gallery
[previous Augusts: 2009, 2008, 2007, 2006, 2005, 2004, 2003]

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 September 4, 2010 there were 1144 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2010 RC
Aug 29
9.3 LD
23 m
2002 CY46
Sep 2
63.8 LD
2.3 km
2010 QG2
Sep 3
4.6 LD
62 m
2010 RB12
Sep 4
2.5 LD
19 m
2010 LY63
Sep 7
56 LD
1.2 km
2009 SH2
Sep 30
7.1 LD
45 m
1998 UO1
Oct 1
32.1 LD
2.1 km
2005 GE59
Oct 1
77 LD
1.1 km
2001 WN5
Oct 10
41.8 LD
1.0 km
1999 VO6
Oct 14
34.3 LD
1.8 km
1998 TU3
Oct 17
69.1 LD
5.3 km
1998 MQ
Oct 23
77.7 LD
1.9 km
2007 RU17
Oct 29
40.6 LD
1.0 km
2003 UV11
Oct 30
5 LD
595 m
3838 Epona
Nov 7
76.8 LD
3.4 km
2005 QY151
Nov 16
77.7 LD
1.3 km
2008 KT
Nov 23
5.6 LD
10 m
2002 EZ16
Nov 30
73.9 LD
1.0 km
2000 JH5
Dec 7
47 LD
1.5 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 Dynamics Observatory
  Researchers call it a "Hubble for the sun." SDO is the most advanced solar observatory ever.
  3D views of the sun from NASA's Solar and Terrestrial Relations Observatory
Solar and Heliospheric Observatory
  Realtime and archival images of the Sun from SOHO.
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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