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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: 618.2 km/s
2.7 protons/cm3
explanation | more data
Updated: Today at 2245 UT

X-ray Solar Flares
6-hr max:
A0 2130 UT Apr02
24-hr: A0 0330 UT Apr02
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 02 Apr '07

After nearly disappearing yesterday, sunspot 949 is growing again. It is still too small, however, for solar flares. Credit: SOHO/MDI

Sunspot Number: 13
What is the sunspot number?
Updated: 01 Apr 2007

Far Side of the Sun

This holographic image reveals no large sunspots on the far side of the sun. Image credit: SOHO/MDI

Interplanetary Mag. Field
Btotal: 4.8 nT
1.9 nT south
explanation | more data
Updated: Today at 2246 UT

Coronal Holes:

Earth is entering a solar wind stream flowing from the indicated coronal hole. 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 2007 Apr 02 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 2007 Apr 02 2203 UTC
0-24 hr 24-48 hr
ACTIVE 30 % 15 %
MINOR 20 % 10 %
SEVERE 05 % 01 %

High latitudes
0-24 hr 24-48 hr
ACTIVE 40 % 40 %
MINOR 25 % 25 %
SEVERE 10 % 05 %

What's Up in Space -- 2 Apr 2007
Subscribe to Space Weather News

Did you miss last night's auroras? Next time get a wake-up call from Spaceweather PHONE.

EGG MOON: According to folklore, tonight's full Moon is the Egg Moon. Go outside and take a look. You might get some good ideas for decorating Easter eggs. Craters, rays, mountain ranges--finally, you can put all those cracked shells to good use!

WEEKEND AURORAS: A solar wind stream hit Earth on April 1st, sparking a mild but pretty geomagnetic storm. Daryl Pederson took this picture from Indian, Alaska:

"I saw the pilot veer over to fly between the auroral arcs on his decent into Anchorage," says Pederson. "April Fools! It's just an illusion. The auroras were at least 50 miles above the airplane." Indeed, only the space shuttle can fly through auroras: full story.

More auroras are possible tonight. Earth is still inside the solar wind stream, and a good gust could spark another display.

April 2007 Aurora Gallery
[aurora alerts] [night-sky cameras]

KEEP LOOKING UP: "You never know what you'll see in the sky," says Brian Karczewski of Riverside, California. "I was at the Riverside air show Saturday when we heard on the scanner of an unidentified aircraft in the area. We looked up and caught this!"

"He appears to have drawn a face, the air-boss said over the scanner. It's not astronomy, but it sure is cool."

(Actually, happy faces are a well-known and serious facet of astronomy. Examples: the happy face on Mars, the Cheshire Moon, and the circumzenithal arc.)

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 2 Apr 2007 there were 855 known Potentially
Hazardous Asteroids

April 2007 Earth-asteroid encounters




2006 VV2

Mar. 31

8.8 LD


2 km
2007 FY20

Apr. 2

5.3 LD


50 m
2007 DS84

Apr. 14

16 LD


325 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.

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 -- from the National Solar Data Analysis Center

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

What is the Magnetosphere?

The Lion Roars -- visit this site to find out what the magnetosphere sounds like.

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

Observable Comets -- from the Harvard Minor Planet Center.

Real-time Solar Wind Data -- from NASA's ACE spacecraft.

How powerful are solar wind gusts? Not very! 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 1996 to 2006

Mirages: Mirages in Finland; An Introduction to Mirages;

NOAA Solar Flare and Sunspot Data: 1994, 1995, 1996, 1997, 1998, 1999; 2000; 2001; 2002; 2003; 2004; 2005; Jan-Mar 2006; Apr-Jun 2006; Jul-Sep 2006; Oct-Dec 2006.

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

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