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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: 530.6 km/s
4.9 protons/cm3
explanation | more data
Updated: Today at 2222 UT

X-ray Solar Flares

6-hr max:
B2 1650 UT Jan23
24-hr: B3 1615 UT Jan23
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 23 Jan '04
None of these sunspots pose a threat for strong solar flares. Image credit: SOHO/MDI

The Far Side of the Sun

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

Sunspot Number: 76
What is the sunspot number?
Updated: 22 Jan 2004

Interplanetary Mag. Field
Btotal: 9.6 nT
3.8 nT south
explanation | more data
Updated: Today at 2223 UT

Coronal Holes:

There are no big coronal holes on the Earth-facing side of the sun today. 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 2004 Jan 23 2200 UTC
FLARE 0-24 hr 24-48 hr
CLASS M 20 % 15 %
CLASS X 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 2004 Jan 23 2200 UTC
0-24 hr 24-48 hr
ACTIVE 30 % 25 %
MINOR 15 % 10 %
SEVERE 05 % 05 %

High latitudes
0-24 hr 24-48 hr
ACTIVE 35 % 25 %
MINOR 20 % 15 %
SEVERE 10 % 05 %

What's Up in Space -- 23 Jan 2004
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AURORA WATCH: A mild geomagnetic storm is in progress; high-latitude sky watchers should be alert for auroras. This activity is caused by two coronal mass ejections (CME) hitting Earth's magnetic field: once on Jan. 22nd and again (weakly) on Jan. 23rd. Furthermore, the interplanetary magnetic field near Earth is tilting south--a condition that favors geomagnetic storms.

Would you like a call when auroras appear in your area? Sign up for Spaceweather PHONE.

SOLAR ACTIVITY: On Jan. 21st a magnetic filament of hot gas big enough to hold 50 planet Earths rose above the limb of the sun. Gary Palmer of Los Angeles, CA, took this picture of it using his Coronado NearStar telescope: (continued below)

In Louisville, Colorado, Vern Raben photographed it, too (image). "Oh wow!" says Raben. "There were numerous intricate spiraling loops hovering above the Sun's west limb. It was one of the most spectacular prominences I have ever seen!"

On Jan. 22nd the prominence erupted, hurling a billion-ton cloud of gas into space. Although the blast was not directed at Earth, there is a slim chance that the cloud will brush past our planet's magnetic field on Jan. 24th and cause some high-latitude auroras.

SUN MIRAGE: The temperature outside was -45 F, and Graham Stark of Fairbanks, Alaska, didn't want to leave the house. "I was afraid the camera would freeze to my hand." So he took this picture through a thick window. It's the sun. "I have never witnessed such extreme distortions of the sun. At one point it took the shape of a square and at another it resembled a frog." More images: #1, #2, #3.

Atmospheric optics expert Les Cowley explains: "This fantastic shaped sun is an example of a complex mirage formed when there is a temperature inversion, a layer of cooler air sandwiched between two hotter layers. Inversions can produce multiple images; each part of the shape is a mirage of a particular slice across the sun. As the altitude of the sun changes or the air layers shift the distorted slices fatten or slim."

"We sometimes think of mirages as a summer sight over hot tarmac or deserts," he adds, "but Stark's photos show that they can occur also when it is very cold. "

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 are on a collision course with our planet, although astronomers are finding new ones all the time.

On 23 Jan 2004 there were 569 known Potentially
Hazardous Asteroids

December 2003 Earth-asteroid encounters


2003 YS17

Jan 14

14 LD

2001 BE10

Jan 15

23 LD

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 --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 Soft 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

The Sun from Earth -- daily images of our star 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.

Aurora Forecast --from the University of Alaska's Geophysical Institute

Daily Solar Flare and Sunspot Data -- from the NOAA Space Environment Center.

Lists of Coronal Mass Ejections -- from 1998 to 2001

What is an Iridium flare? See also Photographing Satellites by Brian Webb.

Vandenberg AFB missile launch schedule.

What is an Astronomical Unit, or AU?

Mirages: Mirages in Finland; An Introduction to Mirages;

NOAA Solar Flare and Sunspot Data: 1999; 2000; 2001; 2002; Jan-Mar., 2003; Apr-Jun., 2003;

Recent International Astronomical Union Circulars


Editor's Note: This site is sponsored by Science@NASA. Space weather and other forecasts that appear here are formulated by Dr. Tony Phillips. They should not be construed as guarantees of space weather or other celestial activity.

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