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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
SPACE WEATHER
Current conditions
Solar wind
speed: 284.8 km/sec
density: 2.1 protons/cm3
explanation | more data
Updated: Today at 2323 UT
X-ray Solar Flares
6-hr max: A6
1855 UT Aug21
24-hr: A9
0000 UT Aug21
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 21 Aug 10
The Earth-facing side of the sun is blank-no sunspots. Solar activity is low.
Resolutions: 4096, 1024, 512
Sunspot number: 0
What is the sunspot number?
Updated 20 Aug 2010

Spotless Days
Current Stretch: 1 day
2010 total: 36 days (16%)
2009 total: 260 days (71%)
Since 2004: 803 days
Typical Solar Min: 486 days
explanation | more info
Updated 20 Aug 2010


The Radio Sun
10.7 cm flux: 78 sfu
explanation | more data
Updated 19 Aug2010

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 2
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 3.6 nT
Bz: 1.4 nT north
explanation | more data
Updated: Today at 2325 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole could reach Earth on Aug. 24th or 25th. Credit: SDO/AIA
SPACE WEATHER
NOAA Forecasts
Updated at: 2010 Aug 21 2201 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: 2010 Aug 21 2201 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
What's up in Space
August 21, 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.

 

JACK HORKHEIMER (1938-2010): Jack Horkheimer, Public Television's "Star Gazer" and the director of Miami's Space Transit Planetarium,' died Friday, August 20th, at the age of 72. Jack was a giant of astronomy outreach, bringing the heavens down to Earth for millions of people from all walks of life. Among them was the author of this web page as a young student in Florida so many years ago. Jack's loss is keenly felt. Farewell, Jack Horkheimer, and "keep looking up!"

SPACE STATION AURORAS: On August 13th a minor solar wind stream hit Earth's magnetic field. The impact did not trigger widespread displays of auroras on Earth, but the view from orbit was sublime:

NASA astronaut Doug Wheelock took the picture from the International Space Station (ISS) and quickly tweeted it down to Earth, captioned by lyrics from the Don McLean ballad "Vincent" (a.k.a. "Starry Starry Night"). Note how the planet directly below the auroras is partially sunlit. The auroras are nevertheless visible against the black, starry backdrop beyond the planet's limb. The ISS is a nice place for sky watching.

Another solar wind stream is heading for Earth, due to arrive on August 24th (see "Coronal Hole," below). Stay tuned to Wheelock's twitter feed for more aurora sightings from space.

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

CORONAL HOLE: A coronal hole on the sun is turning to face Earth. Coronal holes are places in the sun's atmosphere where the magnetic field opens up and allows solar wind to escape. Here is a magnetic map of the hole from NASA's Solar Dynamics Observatory:


Image credit: Karel Schrijver, Lockheed Martin SAL

In the image, magnetic field lines are color-coded. White field lines are closed; they hold the solar wind in. Golden-brown field lines are open; they allow the solar wind out.

A stream of solar wind flowing from this coronal hole is expected to reach Earth on August 24th or 25th. High-latitude sky watchers should be alert for auroras when it arrives.


2010 Perseid Photo Gallery
[meteor radar] [Perseid fireball cam]

 
       
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 21, 2010 there were 1144 potentially hazardous asteroids.
Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2002 CY46
Sep 2
63.8 LD
16
2.4 km
2010 LY63
Sep 7
56 LD
18
1.2 km
2009 SH2
Sep 30
7.1 LD
25
45 m
1998 UO1
Oct 1
32.1 LD
17
2.1 km
2005 GE59
Oct 1
77 LD
18
1.1 km
2001 WN5
Oct 10
41.8 LD
18
1.0 km
1999 VO6
Oct 14
34.3 LD
17
1.8 km
1998 TU3
Oct 17
69.1 LD
15
5.3 km
1998 MQ
Oct 23
77.7 LD
17
1.9 km
2007 RU17
Oct 29
40.6 LD
18
1.0 km
2003 UV11
Oct 30
5 LD
19
595 m
3838 Epona
Nov 7
76.8 LD
16
3.4 km
2005 QY151
Nov 16
77.7 LD
18
1.3 km
2008 KT
Nov 23
5.6 LD
28
10 m
2002 EZ16
Nov 30
73.9 LD
18
1.0 km
2000 JH5
Dec 7
47 LD
17
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 and Heliospheric Observatory
  Realtime and archival images of the Sun from SOHO.
STEREO
  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...
   
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