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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 353.8 km/sec
density: 2.4 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A6
1855 UT May02
24-hr: A6
1855 UT May02
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 02 May 09
Sunspot 1016 has disappeared over the sun's western limb.. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 02 May 2009

NEW: Spotless Days
Current Stretch: 2 days
2009 total: 106 days (87%)
Since 2004: 617 days
Typical Solar Min: 485 days
explanation | more info
Updated 02 May 2009

Far side of the Sun:
This holographic image reveals no sunspots on the far side of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 5.5 nT
Bz: 2.1 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on or about May 6th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 May 02 2201 UTC
0-24 hr
24-48 hr
01 %
01 %
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: 2009 May 02 2201 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
What's up in Space
May 2, 2009

AURORA ALERT: Did you sleep through the Northern Lights? Next time get a wake-up call: Spaceweather PHONE.


SOLAR PROMINENCES: Today, the solar prominence count is seven. The largest one is a gorgeous arch shown here in a photo from amateur astronomer James Screech of Bedford, England. "I took the picture using my Personal Solar Telescope," he says. For scale, a pair of planet Earth's could fit through the enormous loop with room to spare.

BLANKETY-BLANK SUN: Sunspot 1016 has vanished. Yesterday it rotated over the western limb of the sun where it can no longer be seen from Earth. But has it really vanished? According to NASA's STEREO-A spacecraft, the sunspot still exists. It is circled in this extreme UV image just beamed back to Earth:

STEREO-A is stationed above the western limb of the sun. From that vantage point, the spacecraft can track sunspots for days after they leave the range of terrestrial telescopes. Back on Earth, the sunspot number has dropped to zero, but STEREO-A is still counting.

So is the sun blank--or not? For more than 200 years, astronomers have counted spots on the Earth-facing side of the sun and called that the sunspot number. Farside spots couldn't be seen and didn't count. Continuing this tradition makes sense because it allows us to compare data across the centuries. So, today, the sun is officially blank even if STEREO-A knows better.

MAINE SUNRISE: In Cape Elizabeth, Maine, the last sunrise of April was a doozy. Standing on the shore of Casco Bay on April 30th, photographer John Stetson captured this sequence of images:

"Our sun can appear in interesting shapes," says Stetson with understatement. "This is a result of Earth's atmosphere acting as a lens to refract the light that we see."

Atmospheric optics expert Les Cowley elaborates: "In John’s sequence the solar image struggles upwards through multiple atmospheric temperature inversion layers. Each has unusually cooler air trapped beneath warmer, and each splits the sun’s light into two images – one rising, one inverted and sinking. Where they overlap we see a bulging 'spare tire'! Such mirages are the stuff of a special type of green flash, a 'mock-mirage' that is frequently photographed but is very rarely seen with the unaided eye."

A close-up look at the distorted sun reveals even more: "John has caught several instances of the green upper rim flash and lower 'red flashes' where the last fragment of an image caught between inversion layers is reddened and vertically stretched."

What kind of sunrises will May bring? Stay tuned.

April 2009 Aurora Gallery
[previous Aprils: 2008, 2007, 2006, 2005, 2004, 2003, 2002]

Explore the Sunspot Cycle

Near-Earth Asteroids
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 May 2, 2009 there were 1054 potentially hazardous asteroids.
May 2009 Earth-asteroid encounters:
Miss Distance
2009 JA
May 4
7.5 LD
37 m
2006 FG3
May 6
60.7 LD
1.1 km
2001 SG286
May 17
11.5 LD
280 m
Notes: LD means "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 Links
NOAA Space Weather Prediction Center
  The official U.S. government space weather bureau
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.
  3D views of the sun from NASA's Solar and Terrestrial Relations Observatory
Daily Sunspot Summaries
  from the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
Science Central
  more links...
©2008, -- This site is penned daily by Dr. Tony Phillips.
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