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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 525.2 km/sec
density: 2.1 protons/cm3
explanation | more data
Updated: Today at 2342 UT
X-ray Solar Flares
6-hr max: M2
1755 UT Jan20
24-hr: M2
1755 UT Jan20
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 20 Jan. 10
Old sunspot 1039 (soon to renamed "new sunspot 1041") should emerge today in the circled area. Image credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 19 Jan 2010

Spotless Days
Current Stretch: 0 days
2010 total: 2 days (11%)
2009 total: 260 days (71%)
Since 2004: 772 days
Typical Solar Min: 485 days
explanation | more info
Updated 19 Jan 2010

The Radio Sun
10.7 cm flux: 84 sfu
explanation | more data
Updated 19 Jan 2010

Far side of the Sun:
This holographic image reveals no sunspots on the far side of the sun. The holographic technique used to map the farside is evidently not sensitive enough to detect farside spot 1039. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 4 unsettled
24-hr max: Kp= 5
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 5.0 nT
Bz: 0.4 nT south
explanation | more data
Updated: Today at 2344 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: 2010 Jan 20 2201 UTC
0-24 hr
24-48 hr
75 %
75 %
05 %
05 %
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 Jan 20 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
January 20, 2010

SATELLITE FLYBYS APP: Turn your iPhone or iPod into a field-tested satellite tracker! presents the Satellite Flybys app.


AURORA ALERT: High-latitude sky watchers should be alert for auroras. Earth is entering a dense solar wind stream and this could trigger polar geomagnetic storms.

CRACKLING SUNSPOT: Old sunspot 1039 is crackling with solar flares. Over the past 48 hours, it has produced five M-class eruptions. Click on the image to play a movie of the latest, an M2-blast recorded by STEREO-B at 1756 GMT on Jan. 20th:

The ongoing sequence of flares signals a sharp upturn in solar activity. Before this week, the last time the sun produced even a single M-class solar flare was in March 2008--almost two years ago. M-class solar flares have a moderate effect on Earth. Mainly, they boost the usual ionization of Earth's upper atmosphere, causing short-lived radio blackouts at some frequencies and radio enhancements at others. For an example, scroll down and read the section "Ionospheric Disturbance."

Today, the active region responsible for these fireworks is emerging over the sun's eastern limb where it can be seen from Earth: finder chart. Readers with solar telescopes are encouraged to monitor developments.

IONOSPHERIC DISTURBANCE: An M2-class solar flare on Jan. 19th bathed Earth's upper atmosphere in X-rays and caused a wave of ionization to sweep over Europe. This improved the propagation of low-frequency radio signals, which use the ionosphere as a reflector to skip over the horizon. A SID monitor operated by Rudolf Slosiar in Bojnice, Slovakia, recorded a surge in signal strength:

"SID" stands for Sudden Ionospheric Disturbance, and a "SID monitor" is a radio receiver that monitors ~20 kHz signals from distant transmitters. "My system clearly detected the effects of the solar flare," says Slosiar. "The decay of the signal shows that it took about 72 minutes for the ionosphere to recombine [and relax to its pre-flare state]."

With solar activity on the rise, sudden ionospheric disturbances will become more common. Interested? Stanford University tells you how to build your own SID monitor.

more SIDS: from Roberto Battaiola of Pantigliate, Milano, Italy;

January Northern Lights Gallery
[previous Januarys: 2009, 2008, 2007, 2005, 2004, 2001]

UPDATED: Solar Eclipse Photo Gallery
[World Map of Eclipse Sightings]

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 January 20, 2010 there were 1093 potentially hazardous asteroids.
Jan. 2010 Earth-asteroid encounters:
Miss Distance
2010 AL2
Jan. 11
11.5 LD
23 m
24761 Ahau
Jan. 11
70.8 LD
1.4 km
2000 YH66
Jan. 12
69.5 LD
1.1 km
2010 AL30
Jan. 13
0.3 LD
18 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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