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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 377.2 km/sec
density: 0.4 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: M6
2056 UT Jul28
24-hr: M6
2056 UT Jul28
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 28 Jul 12
Sunspot AR1532 poses a growing threat for M-class solar flares. Credit: SDO/HMI
Sunspot number: 91
What is the sunspot number?
Updated 28 Jul 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 28 Jul 2012

The Radio Sun
10.7 cm flux: 123 sfu
explanation | more data
Updated 28 Jul 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 3
explanation | more data
Interplanetary Mag. Field
Btotal: 6.6 nT
Bz: 1.7 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 28 Jul 12
A solar wind stream flowing from this coronal hole should reach Earth on July 29-30. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2012 Jul 28 2200 UTC
0-24 hr
24-48 hr
25 %
25 %
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 Jul 28 2200 UTC
0-24 hr
24-48 hr
30 %
30 %
15 %
15 %
05 %
05 %
High latitudes
0-24 hr
24-48 hr
10 %
10 %
20 %
20 %
45 %
45 %
Saturday, Jul. 28, 2012
What's up in space

They came from outer space--and you can have one! Genuine meteorites are now on sale in the Space Weather Store.

Own your own meteorite

MARS LANDING SKY SHOW: On the same night Curiosity lands on Mars, a "Martian Triangle" will appear in sunset skies of Earth. The first-magnitude apparition on August 5th gives space fans something to do while they wait for news from the Red Planet. [video]

M6-CLASS FLARE: Solar activity is picking up. For the second day in a row, sunspot AR1532 has unleashed a moderately-strong solar flare. The latest, an M6-class eruption, occurred on July 28th at 2056 UT. NASA's Solar Dynamics Observatory captured the extreme UV flash:

It is too soon to say if the eruption produced a coronal mass ejection (CME). If it did, Earth would likely receive no more than a glancing blow from the cloud. The sunspot is too far off disk center to be very geoeffective. This could change in the days ahead, however, as the sunspot turns toward Earth. Stay tuned for updates. Solar flare alerts: text, voice.

METEOR ACTIVITY INCREASES: Last night, NASA's All Sky Fireball Network detected 17 Venus-bright meteors. The orbits of the meteoroids, color-coded by velocity, are shown in the diagram below. Earth's location is marked by a red starburst:

The green orbits correspond to Comet 96P/Machholz, source of the annual delta Aquarid meteor shower. Although this is a minor shower, it is fraught with interest. Some researchers believe that 96P/Machholz came from another star system. Every delta Aquarid that disintegrates in the night sky could be depositing material from across the galaxy into Earth's upper atmosphere.

Forecasters expect as many as 15 delta Aquarids per hour when the shower peaks on July 28th and 29th. The best time to look, no matter where you live, is during the dark hours before sunrise on Saturday and Sunday when the moon has set and the constellation Aquarius is relatively high in the sky.

Blue orbits correspond mainly to Perseids. The Perseid meteor shower doesn't peak until August 12-13, but Earth is already in the outskirts of the debris zone of the parent comet, 109P/Swift-Tuttle. By mid-August, rates could exceed 100 meteors per hour. The show, in other words, is just getting started.

Got clouds? Try listening to meteor radar echoes on Space Weather Radio.

Realtime Space Weather Photo Gallery

Realtime Noctilucent Cloud Photo Gallery
[previous years: 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2011]

  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 July 28, 2012 there were 1323 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2002 AM31
Jul 22
13.7 LD
1.0 km
2012 OQ
Jul 24
7.7 LD
190 m
2012 OU1
Jul 25
8.5 LD
54 m
37655 Illapa
Aug 12
37 LD
1.2 km
2000 ET70
Aug 21
58.5 LD
1.1 km
1998 TU3
Aug 25
49.2 LD
4.9 km
2009 AV
Aug 26
62.8 LD
1.1 km
1998 UO1
Oct 4
60.1 LD
2.1 km
2005 GQ21
Oct 12
77 LD
1.0 km
1998 ST49
Oct 18
28.7 LD
1.3 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.
  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
  the underlying science of space weather
Trade Show Displays
  more links...
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