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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 349.5 km/sec
density: 0.1 protons/cm3
explanation | more data
Updated: Today at 2341 UT
X-ray Solar Flares
6-hr max: B6
1708 UT Apr30
24-hr: C6
1041 UT Apr30
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 30 Apr 12
New sunspot 1472 appeared on April 29th. Credit: SDO/HMI
Sunspot number: 114
What is the sunspot number?
Updated 29 Apr 2012

Spotless Days
Current Stretch: 0 days
2012 total: 0 days (0%)
2011 total: 2 days (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 821 days
Typical Solar Min: 486 days

Updated 29 Apr 2012


The Radio Sun
10.7 cm flux: 116 sfu
explanation | more data
Updated 29 Apr 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 1
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 3.5 nT
Bz: 1.9 nT south
explanation | more data
Updated: Today at 2344 UT
Coronal Holes: 30 Apr 12
There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2012 Apr 30 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
10 %
10 %
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: 2012 Apr 30 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
25 %
25 %
MINOR
10 %
10 %
SEVERE
01 %
01 %
 
Monday, Apr. 30, 2012
What's up in space
 

Listen to radar echoes from satellites and meteors, live on listener-supported Space Weather Radio.

 
Spaceweather Radio is on the air

MARS-DIRECTED CME: A minor CME that left the sun during the late hours of April 28th is heading for Mars. En route, it will sweep past the Mars Science Lab spacecraft, which is carrying Curiosity to the Red Planet. According to a forecast track prepared by analysts at the GSFC, the cloud will reach the rover on May 4th. Fortunately, Curiosity is equipped to sense and study solar storms: video.

THWARTED ESCAPE: Solar activity is low, with only a smattering of minor C-class flares coming from a few 'active regions' scattered across the solar disk. An eruption from sunspot AR1465 on April 29th didn't even get off the ground. NASA's Solar Dynamics Observatory recorded the thwarted escape:

It was AR1465 vs. gravity, and gravity won.

Solar activity should remain low for the next 24 to 48 hours, with no more than a 1% chance of X-class solar flares. As the movie above shows, however, even a weak eruption on the sun is worth watching. Stay tuned for more. Solar flare alerts: text, voice.

more images: from Alan Friedman of Buffalo, NY; from John Stetson of Falmouth, Maine

VENUS IN BROAD DAYLIGHT: Venus is at its brightest. Today, the second planet from the sun is shining 190 times brighter than a 1st magnitude star, bright enough to see in broad daylight if your eye lands right on it. On April 28th in the Czech Republic, something drew Martin Gembec's eye directly to Venus. His guide was the International Space Station:

"We had a nice sunny afternoon picnic here in Jablonec," says Gembec. "In the clear blue sky overhead, the ISS went right through Venus. It was a special moment."

No ISS? No problem. Even without a spaceship, you can find Venus by looking 40° (about four fist-widths) east of the sun. Observing tip: Stand in the shadow of a tall building. You can also wait until the sun goes down. Venus is terrifically brilliant in the western twilight.

more images: from Aaron Top of Shallow Lake, Ontario, Canada; from Philip Strohbehn of Webster City, Iowa

FIREBALL PHOTOS WANTED: Meteor expert Peter Jenniskens of NASA's Ames Research Center could use some help from the general public--in particular, photographers and business owners with security cameras in central California. He needs photos of the mini-van sized asteroid that exploded over the region on Sunday morning, April 22nd, at 7:51 am PDT. "Our goal is to determine the orbit of the object and to understand how this small asteroid fell apart when it entered the earth's atmosphere," he explains. [Got photos? Submit them here.]

Meteorite hunters, Jenniskens included, are starting to find pieces of the asteroid on the the ground. These samples were lying in the parking lot of Henningsen-Lotus Park, apparently crushed by a passing car:

The meteorites landed not far from Sutter's Mill in El Dorado County, CA, the same place gold was discovered in the 19th century, triggering the California Gold Rush. Jenniskens likens the thrill of finding these space rocks to finding gold: " I think John A. Sutter must have felt the same way when he found the first gold nugget back in January of 1848."

"The meteorites appear to be CM chondrites," he continues. This would make the sample very primitive, possibly contiaining minerals and compounds preserved from a time when the solar system was very young. "I can not say more as the samples have not yet been analyzed. My main concern now is to recover perishable data of the fireball, such as video security camera footage."

More footage will help researchers answer questions like these: "Was this a rubble pile or a monolitihic block? Was the orbit very evolved, or could its semi-major axis perhaps still point us to the source region of CM chondrites in the asteroid belt?" Jeniskens wonders. "This is a rare opportunity to learn about the properties of a particular class of near-Earth objects."

News reports: #1, #2, #3.

  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 April 30, 2012 there were 1287 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2012 HE2
Apr 24
8.9 LD
--
28 m
2012 HQ
Apr 24
9.8 LD
--
42 m
2012 HP13
Apr 27
2 LD
--
64 m
2012 HM
Apr 28
1.4 LD
--
67 m
2011 WV134
Apr 28
38.6 LD
--
1.6 km
2012 HE31
Apr 30
2.7 LD
--
31 m
1992 JD
May 2
9.5 LD
--
43 m
2010 KK37
May 19
2.3 LD
--
31 m
4183 Cuno
May 20
47.4 LD
--
5.7 km
2002 VX94
May 26
72.8 LD
--
1.1 km
2002 AC
Jun 16
62.2 LD
--
1.2 km
1999 BJ8
Jun 16
68.8 LD
--
1.1 km
2005 GO21
Jun 21
17.1 LD
--
2.2 km
2003 KU2
Jul 15
40.3 LD
--
1.3 km
2004 EW9
Jul 16
46.8 LD
--
2.1 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 web 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 Dynamics Observatory
  Researchers call it a "Hubble for the sun." SDO is the most advanced solar observatory ever.
STEREO
  3D views of the sun from NASA's Solar and Terrestrial Relations Observatory
Solar and Heliospheric Observatory
  Realtime and archival images of the Sun from SOHO.
Daily Sunspot Summaries
  from the NOAA Space Environment Center
Heliophysics
  the underlying science of space weather
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