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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 433.2 km/sec
density: 1.5 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: B5
2151 UT Jan17
24-hr: B5
2151 UT Jan17
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 17 Jan 11
Formerly active sunspot group 1147 remains quiet for the third day in a row. Credit: SDO/HMI
Sunspot number: 15
What is the sunspot number?
Updated 16 Jan 2011

Spotless Days
Current Stretch: 0 days
2011 total: 1 day (6%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 820 days
Typical Solar Min: 486 days

Updated 16 Jan 2011

The Radio Sun
10.7 cm flux: 80 sfu
explanation | more data
Updated 16 Jan 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 2
explanation | more data
Interplanetary Mag. Field
Btotal: 3.3 nT
Bz: 1.8 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 17 Jan 10
A solar wind stream flowing from the indicated coronal hole should reach Earth on Jan. 19th or 20th. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Jan 17 2200 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: 2011 Jan 17 2200 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
10 %
10 %
01 %
01 %
01 %
01 %
Monday, Jan. 17, 2011
What's up in space

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

Satellite flybys

ASTEROID FLYBY: Newly-discovered asteroid 2011 AN52 is flying past Earth today just inside the orbit of the Moon (0.8 LD). The space rock is only 8 meters wide, about the size of a small room, so even experienced amateur astronomers will have trouble photographing it as it zips through the northern constellations Draco and Cygnus glowing like an 18th magnitude star. But it is there: 3D orbit, ephemeris.

AURORAS, NON-STOP: "The beauty of the Arctic is in full swing," says photographer Fredrik Broms of Kvaløya, Norway. "Strong auroras have been observed each night for a full week now, beginning after nightfall and going on most of the night until early morning. A particularly nice display came on Jan. 13th when the sky exploded in green and purple. Bright moonlight only added to the beauty." As an example, he offers this shot of "a very happy aurora watcher" in the Norwegian mountains:

The non-stop display might be coming to a temporary end. Earth is exiting the solar wind stream that sparked the brightest lights, and the next stream is not due to arrive until Jan. 19-20. Photographers, take this opportunity to recharge your cameras and, of course, be alert for auroras.

UPDATED: January 2011 Aurora Photo Gallery
[previous Januaries: 2010, 2009, 2008, 2007, 2005, 2004]

SUN PILLAR: "Yesterday at sunrise, a column of light jumped straight up from the sun," says Shulamit Widawsky of Fairfax, VA. "It was not a result of the photography. It really looked like this with the naked eye, and lasted for at least ten minutes. What do you call it?" Scroll down for the answer:

This is called a "sun pillar." It is caused by plate-shaped ice crystals fluttering to Earth like leaves falling from trees. Air resistance causes the flat faces of the ice crystals to line up almost parallel to the ground. They catch the light of the morning sun and spread it into a brilliant vertical column. The source of the crystals may be seen in Widawsky's snapshot: icy clouds just above the pillar are responsiible for the display. With air temperatures in the northern hemisphere regularly dipping below freezing, this is a good time of year to see the phenomenon. Look for sun pillars are sunrise and sunset!

more sun pillars: from Chris Deutsch of Effort, Pennsylvania; from Daryl Pederson of south central Alaska; from Robbert-Jan Westerduin of Nijmegen, The Netherlands

Solar Eclipse Photo Gallery
[NASA: Hinode Observes Annular Solar Eclipse]

  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 17, 2011 there were 1183 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2011 AH5
Jan 13
3.3 LD
28 m
2011 AY22
Jan 14
4.1 LD
17 m
2011 AN52
Jan 17
0.8 LD
8 m
2011 AB37
Jan 19
9.5 LD
29 m
2011 AL37
Jan 28
2.4 LD
65 m
2003 YG118
Feb 20
67.7 LD
1.8 km
2000 PN9
Mar 10
45.5 LD
2.6 km
2002 DB4
Apr 15
62.5 LD
2.2 km
2008 UC202
Apr 27
8.9 LD
10 m
2009 UK20
May 2
8.6 LD
23 m
2008 FU6
May 5
75.5 LD
1.2 km
2003 YT1
May 5
65.3 LD
2.5 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 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.
  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
  the underlying science of space weather
Science Central
  more links...
©2010 All rights reserved. This site is penned daily by Dr. Tony Phillips.
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