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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 371.8 km/sec
density: 0.9 protons/cm3
explanation | more data
Updated: Today at 2245 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Apr21
24-hr: A0
0200 UT Apr21
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 21 Apr 08
Sunspot 991 is is almost invisibly tiny, but it is there. Credit: SOHO/MDI
Sunspot number: 12
What is the sunspot number?
Updated 19 Apr 2008
Far side of the Sun:
This holographic image reveals no large sunspots on the farside 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: 1.8 nT
Bz: 1.1 nT south
explanation | more data
Updated: Today at 2245 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on or about April 25th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2008 Apr 21 2203 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: 2008 Apr 21 2203 UTC
0-24 hr
24-48 hr
25 %
40 %
10 %
15 %
05 %
05 %
High latitudes
0-24 hr
24-48 hr
25 %
45 %
15 %
20 %
05 %
10 %
What's up in Space
April 21, 2008
FLYBY ALERT! Would you like a phone call when the International Space Station (ISS) is about to fly over your back yard? Sign up for Space Weather PHONE.  

LYRID METEORS: The annual Lyrid meteor shower caused by dust from Comet Thatcher is underway. Forecasters expect the display to peak on Tuesday morning, April 22nd. Unfortunately, full moonlight threatens to spoil the show; most Lyrids are simply not bright enough to pierce the glare. Is it worth waking up hours before sunrise on Tuesday to see no more than a sprinkling of meteors? You decide.

INTRODUCING EMINESCU: Mihai Eminescu is well known in Romania: Schools are named after him; statues in his likeness may be found in public squares; his face is printed on paper money; you have to recite his words to graduate from high school. He is the national poet of Romania, revered for his romantic works of the 19th century.

Now meet Eminescu, the crater:

Named just last week by the International Astronomical Union, crater Eminescu was discovered by NASA's MESSENGER spacecraft during its historic flyby of the planet Mercury on Jan. 14, 2008. The flyby revealed 6 million square miles of previously unseen terrain and thousands of new craters. Craters on Mercury are named after great artists such as Matisse, Vivaldi, Mozart ... and now Eminescu.

Crater Eminescu is intriguing for several reasons: (1) It is relatively young; we know this because it has few other craters superposed on top of it. (2) Eminescu is surrounded by an impressive spray of secondary crater chains (diagram) tracing the splash of impact. (3) The ring of peaks at Eminescu's center is slightly blue. On a relentlessly gray world like Mercury, that's very strange.

In 1877 or so, Eminescu the man fell in love with a Moldavian poetess, Veronica Micleand, and in her honor he wrote one of the great love poems of all time: Luceafarul, the "Evening Star." Now Eminescu has a unique place on Mercury, the evening star itself.

MOONDUST AND DUCT TAPE: Going to the Moon? Don't forget your duct tape. Thirty-six years ago when Apollo 17 astronauts found themselves a quarter million miles from home with a damaged moonbuggy, a roll of "good old fashioned American gray tape" saved the day: full story.

3D BONUS: Grab your 3D glasses and examine the Apollo 17 moonbuggy:

Credit: Gene Cernan, Apollo 17, NASA; Anaglyph by Erik van Meijgaarden

The fenders, which appear vividly in this 3D representation, were a source of trouble during the Apollo 17 Moon landing. Shortly after unloading the rover from its storage compartment in the lunar lander Challenger, astronaut Gene Cernan accidentally snagged one of the rear fenders with a hammer. Half of the fender was torn off and he was forced to make impromptu repairs using "good old-fashioned American gray tape." The movie of Cernan tearing tape from a roll in thick spacesuit gloves is a must-see.

April 2008 Aurora Gallery
[Aurora Alerts] [Night-sky Cameras]

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. [comment]
On April 21, 2008 there were 946 potentially hazardous asteroids.
April 2008 Earth-asteroid encounters:
Miss Distance
2008 FH5
Apr. 2
7.6 LD
17 m
2001 QO142
Apr. 6
34 LD
685 m
2008 GF1
Apr. 7
0.8 LD
10 m
2005 BE2
Apr. 10
62 LD
1.0 km
2005 NB7
Apr. 17
16 LD
705 m
2008 FU6
Apr. 22
62 LD
1.4 km
2005 TB
Apr. 28
47 LD
1.3 km
2001 DQ8
Apr. 30
74 LD
1.1 km
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 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.
Daily Sunspot Summaries
  From the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
  more links...
©2008, -- This site is penned daily by Dr. Tony Phillips.
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