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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 374.5 km/sec
density: 1.1 protons/cm3
explanation | more data
Updated: Today at 0943 UT
X-ray Solar Flares
6-hr max: B4
2132 UT Aug28
24-hr: B5
1400 UT Aug28
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 28 Aug 11
A new sunspot is emerging at the circled location. Credit: SDO/HMI
Sunspot number: 63
What is the sunspot number?
Updated 27 Aug 2011

Spotless Days
Current Stretch: 0 days
2011 total: 2 days (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 821 days
Typical Solar Min: 486 days

Updated 27 Aug 2011


The Radio Sun
10.7 cm flux: 104 sfu
explanation | more data
Updated 27 Aug 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 7.8 nT
Bz: 2.1 nT south
explanation | more data
Updated: Today at 2344 UT
Coronal Holes: 28 Aug 11
A solar wind stream flowing from the indicated coronal hole should reach Earth on Aug. 28-29. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Aug 28 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
01 %
01 %
CLASS X
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: 2011 Aug 28 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
15 %
MINOR
05 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
25 %
20 %
MINOR
10 %
05 %
SEVERE
01 %
01 %
 
Sunday, Aug. 28, 2011
What's up in space
 

Turn your cell phone into a field-tested satellite tracker. Works for Android and iPhone.

 
Satellite flybys

SOLAR EXPLOSION: This morning at 0430 UT, the magnetic canopy of departing sunspot 1271 erupted, producing a B5-class solar flare and hurling a CME into space. The beautiful blast was not Earth-directed and will not affect our planet.

more images: from SDO in Earth orbit; from Stratos Tsanaktsidis of Thessaloniki, Greece

COMET GARRADD MEETS M71: This weekend, amateur astronomers around the world are watching the green tail of Comet Garradd (C/2009 P1) sweep across golden star cluster M71. Nick Howes sends this picture of the encounter from Cherhill in Wiltshire UK:

In New Hampshire, Tim Printy photographed the pair "just before the weather in New England turned sour due to the approaching hurricane," he says. "In binoculars, they looked like twin fuzzy patches."

Discovered two years ago by Gordon Garradd in Australia, the 8th-magnitude comet is currently visible through small telescopes in the constellation Sagitta inside the evening Summer Triangle (finder charts). The comet is approaching the sun and brightening; recent projections place it at peak magnitude 6 in February 2012, just at the limit of naked eye visibility. Because Comet Garradd is a first-time visitor to the inner solar system, however, it could behave in unexpected ways. Stay tuned for surprises. [3D orbit] [Comet Hunter Telescope]

more images: from Marek Harman of Vartovka observatory, Banská Bystrica, Slovakia; from Karl Beck of Observatory Michelbach, Austria; from Jimmy Westlake of Stagecoach, Colorado; from Marian Urbaník of Čadca, Slovak republic; from Becky Ramotowski of Tijeras, New Mexico; from Csaba Hadhazi of Hajduhadhaz, Hungary; from Andrew Mccrea of Bangor, Northern Ireland; from Bob Runyan of AstroAsylum BYO, Shelton, NE, USA

RED SPRITES: High above Earth in the realm of meteors and noctilucent clouds, a strange and beautiful form of lightning dances at the edge of space. Researchers call the bolts "sprites"; they are red, fleeting, and tend to come in bunches. Martin Popek of Nýdek in the Czech republic photographed these specimens on August 27th:

"Sprites are a true space weather phenomenon," explains lightning scientist Oscar van der Velde of Sant Vicenç de Castellet, Spain. "They develop in mid-air around 80 km altitude, growing in both directions, first down, then up. This happens when a fierce lightning bolt draws lots of charge from a cloud near Earth's surface. Electric fields [shoot] to the top of Earth's atmosphere--and the result is a sprite. The entire process takes about 20 milliseconds."

Although sprites have been seen for at least a century, most scientists did not believe they existed until after 1989 when sprites were photographed by cameras onboard the space shuttle. Now "sprite chasers" routinely photograph sprites from their own homes. "I used up a Watec 902H2 Ultimate security camera with UFOCapture software to catch my sprites," says Popek. Give it a try!

diagram: How to Look for Sprites (used with permission of sky-fire.tv)


UPDATED: August 2011 Aurora Gallery
[previous Augusts: 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2003, 2002]

 

  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 28, 2011 there were 1241 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 QE23
Aug 22
7.6 LD
--
31 m
2009 AV
Aug 22
49.7 LD
--
1.1 km
2003 QC10
Sep 18
50 LD
--
1.2 km
2004 SV55
Sep 19
67.5 LD
--
1.2 km
2007 TD
Sep 23
3.8 LD
--
58 m
2002 AG29
Oct 9
77.1 LD
--
1.0 km
2000 OJ8
Oct 13
49.8 LD
--
2.5 km
2009 TM8
Oct 17
1.1 LD
--
8 m
2011 FZ2
Nov 7
75.9 LD
--
1.6 km
2005 YU55
Nov 8
0.8 LD
--
175 m
1994 CK1
Nov 16
68.8 LD
--
1.5 km
1996 FG3
Nov 23
39.5 LD
--
1.1 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 web 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.
STEREO
  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
Heliophysics
  the underlying science of space weather
Science Central
 
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