SPACE WEATHER
Current
Conditions

Solar Wind
speed: 343.3 km/s
density: 0.9 protons/cm³
explanation | more data
Updated: Today at 2254 UT

X-ray Solar Flares
6-hr max: B1 1930 UT Sep26
24-hr: B1 1605 UT Sep26
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 24 Sep '04
Sunspot 673 does not pose a threat for strong solar flares. Image credit: Big Bear Solar Observatory.

NOTE: SOHO (the Solar and Heliospheric Observatory) is passing through a telemetry keyhole. Daily Sun and other images from SOHO will return to Spaceweather.com when the spacecraft emerges from the keyhole on October 1st.

Sunspot Number: 24
What is the sunspot number?
Updated: 25 Sep 2004

Interplanetary Mag. Field
B_total: 4.1 nT
B_z: 0.2 nT south
explanation | more data
Updated: Today at 2255 UT

Coronal Holes:

A solar wind stream flowing from this loosely-organized coronal hole could reach Earth on or about Sept. 28th. Image credit: NOAA's Solar X-ray Imager (SXI)

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.

Sept. 2004 Earth-asteroid encounters

ASTEROID		MISS DISTANCE	MAG.
2003 UX34	Sept. 9	22 LD	18
2004 JA27	Sept. 10	23 LD	19
1998 OX4	Sept. 14	25 LD	18
Toutatis	Sept. 29	4 LD	9

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.

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 lmsal.com.

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; 2003; Jan-Mar., 2004;

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

GLOSSARY | SPACE WEATHER TUTORIAL