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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: 445.6 km/s
1.6 protons/cm3
explanation | more data
Updated: Today at 2246 UT

X-ray Solar Flares
6-hr max:
A9 1920 UT Apr26
24-hr: B1 0140 UT Apr26
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 26 Apr '07

New sunspot 953 poses a slight threat for M-class solar flares. Credit: SOHO/MDI

Sunspot Number: 14
What is the sunspot number?
Updated: 25 Apr 2007

Far Side of the Sun

This April 23rd holographic image reveals two sunspots on the far side of the sun. One of them, sunspot 953, has since emerged on the Earthside. Image credit: SOHO/MDI

Interplanetary Mag. Field
Btotal: 5.9 nT
3.1 nT south
explanation | more data
Updated: Today at 2246 UT

Coronal Holes:

A solar wind stream flowing from the indicated coronal hole should hit Earth on April 28th. 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 26 2203 UTC
FLARE 0-24 hr 24-48 hr
CLASS M 05 % 05 %
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 26 2203 UTC
0-24 hr 24-48 hr
ACTIVE 10 % 30 %
MINOR 01 % 20 %
SEVERE 01 % 05 %

High latitudes
0-24 hr 24-48 hr
ACTIVE 10 % 40 %
MINOR 05 % 25 %
SEVERE 01 % 10 %

What's Up in Space -- 26 Apr 2007
Subscribe to Space Weather News

What's the name of that star? Where's Saturn? Get the answers from mySKY--a fun new astronomy helper from Meade.

AURORA WATCH: A solar wind stream is heading for Earth and it could spark a geomagnetic storm when it arrives on April 28th. Northern sky watchers should be alert for auroras.

NEW SUNSPOT 953: New sunspot 953 is four times wider than Earth and it's putting on a good show for anyone with a solar telescope. This picture comes from P-M Hedén of Vallentuna, Sweden:

Photo details: Orion 80ED, Solarmax 60 filter, Canon Digital Rebel XT.

"I was watching sunspot 953 when an airplane crossed the surface of the sun," explains Hedén. "It was a great sight!" The sunspot appears to be growing, so it may be even more impressive in the days ahead. Stay tuned.

more images: from Pat Stoker of Anaheim, CA; from Cai-Uso Wohler of Bispingen, Germany; from Robert Arnold on the Isle of Skye, Scotland; from David Storey on the Isle of Man, UK; from Chuck Baker of Carlsbad, CA.

BONUS: In Troutdale, Oregon, artist Mark Seibold was so impressed by the view through his SolarMax40 that he decided to paint sunspot 953: portrait. "The sun is alive! " he says.

NIGHT-SHINING CLOUDS: NASA's AIM spacecraft is in Earth orbit today following a flawless Wednesday afternoon launch aboard an Pegasus XL rocket. AIM is on a mission to study mysterious noctilucent clouds, such as these photographed by Jan Koeman from his home in the Netherlands in June 2005:

Photo details: Nikon D70, 400 ISO, 4 second exp.

Noctilucent clouds ("NLCs" for short) were first noticed in the 19th century following the eruption of the Krakatoa volcano. After sunset, electric-blue tendrils would spread across the western sky, mesmerizing onlookers. At first scientists thought the clouds were a side-effect of the eruption, but long after Krakatoa's dust has settled, the clouds are still here. Indeed, they are becoming more widespread. Originally confined to high latitudes such as Canada and Scandinavia, NLCs have been seen in recent years as far south as Viriginia and Colorado.

What causes NLCs? Theories range from space dust to global warming. For the next two years, AIM will scrutinize these clouds from Earth orbit to learn what they may be telling us about our planet.

Noctilucent Cloud Photo Gallery
Visit the gallery for observing tips and sample camera settings.

3D SUN: Put on your 3D glasses. NASA has released the first 3-dimensional images of the sun taken by the STEREO spacecraft. The gallery displays a nice selection of coronal holes, polar plumes and fiery prominences--and there are more to come!

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 26 Apr 2007 there were 858 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
2007 GU1

Apr. 16

2.1 LD


45 m
2007 HA

Apr. 17

6.5 LD


300 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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