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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Science news and information about the Sun-Earth environment.


Solar Wind
speed: 575.0 km/s
2.3 protons/cm3
explanation | more data
Updated: Today at 2236 UT

X-ray Solar Flares

6-hr max:
A0 2145 UT Feb20
24-hr: A0 2145 UT Feb20
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 20 Feb '06

The sun is blank again. Solar activity should remain low. Credit: SOHO/MDI

Sunspot Number: 0
What is the sunspot number?
Updated: 19 Feb 2006

Far Side of the Sun

This holographic image reveals one small sunspot on the far side of the sun. Image credit: SOHO/MDI

Interplanetary Mag. Field
Btotal: 4.6 nT
0.2 nT north
explanation | more data
Updated: Today at 2246 UT

Coronal Holes:

Earth is inside a solar wind stream flowing from the indicated coronal hole. Image credit: SOHO Extreme UV Telescope.


Solar Flares: Probabilities for a medium-sized (M-class) or a major (X-class) solar flare during the next 24/48 hours are tabulated below.
Updated at 2006 Feb 20 2203 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 2006 Feb 20 2203 UTC
0-24 hr 24-48 hr
ACTIVE 20 % 25 %
MINOR 05 % 10 %
SEVERE 01 % 05 %

High latitudes
0-24 hr 24-48 hr
ACTIVE 30 % 35 %
MINOR 15 % 25 %
SEVERE 05 % 15 %

What's Up in Space -- 20 Feb 2006
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The space station is visible in the night sky this month. Would you like to see it? Sign up for Spaceweather PHONE.

QUIET SUN: The sun is blank again--no sunspots. Solar activity should remain very low.

FALSE AURORAS: The sun is quiet and auroras are scarce. The next best thing: false auroras. Michael Gavan photographed some yesterday in Kalamazoo, Michigan:

Also known as light pillars, false auroras are caused by ice crystals in the air, which intercept urban lights and spread them into colorful columns. "These were the most dynamic and beautiful light pillars I have ever seen!" says Gavan. Conditions in Kalamazoo were ideal for these pillars. "The temperature was around 5o F, and the air was filled with very fine diamond dust ice crystals."

HOARFROST: Not all the ice is in the air. On a cold humid day, look along the sides of trees and power poles for beautiful hoarfrost, as shown in this Feb. 11th photo from Barb Robertson of Ottawa, Ontario, Canada:

Hoarfrost is winter's substitute for dew. It forms when the air is moist and the temperature of the tree is below the dew point. The resulting crystals are so delicate that the slightest amount of direct sunlight can vaporize them. "I found these hiding between the planks of my deck," says Robertson. more images: #1, #2, #3.

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 20 Feb 2006 there were 772 known Potentially
Hazardous Asteroids

Feb. 2006 Earth-asteroid encounters




2006 BM55

Feb. 5

8.4 LD


~110 m
2006 BX39

Feb. 10

8.2 LD


~225 m
Notes: LD is a "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 Environment Center -- The official U.S. government bureau for real-time monitoring of solar and geophysical events, research in solar-terrestrial physics, and forecasting solar and geophysical disturbances.

Atmospheric Optics -- the first place to look for information about sundogs, pillars, rainbows and related phenomena. See also Snow Crystals.

Solar and Heliospheric Observatory -- Realtime and archival images of the Sun from SOHO. (European Mirror Site)

Daily Sunspot Summaries -- from the NOAA Space Environment Center.

Current Solar Images --a gallery of up-to-date solar pictures from the National Solar Data Analysis Center at the Goddard Space Flight Center. See also the GOES-12 Solar X-ray Imager.

Recent Solar Events -- a nice summary of current solar conditions from

SOHO Farside Images of the Sun from SWAN and MDI.

The Latest SOHO Coronagraph Images -- from the Naval Research Lab

Daily images from the sun -- from the Big Bear Solar Observatory

List of Potentially Hazardous Asteroids -- from the Harvard Minor Planet Center.

Observable Comets -- from the Harvard Minor Planet Center.

What is the Interplanetary Magnetic Field? -- A lucid answer from the University of Michigan. See also the Anatomy of Earth's Magnetosphere.

Real-time Solar Wind Data -- from NASA's ACE spacecraft. How powerful are solar wind gusts? Read this story from Science@NASA.

More Real-time Solar Wind Data -- from the Solar and Heliospheric Observatory Proton Monitor.

Lists of Coronal Mass Ejections -- from 1998 to 2001

Mirages: Mirages in Finland; An Introduction to Mirages;

NOAA Solar Flare and Sunspot Data: 1996, 1997, 1998, 1999; 2000; 2001; 2002; 2003; 2004; 2005; Jan-Mar 2006;

Space Audio Streams: (University of Florida) 20 MHz radio emissions from Jupiter: #1, #2, #3, #4; (NASA/Marshall) INSPIRE: #1; (Stan Nelson of Roswell, New Mexico) meteor radar: #1, #2;

Recent International Astronomical Union Circulars


This site is penned daily by Dr. Tony Phillips: email

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