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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 382.2 km/sec
density: 6.7 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: A2
1935 UT Sep20
24-hr: A4
0110 UT Sep20
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 18 Sept. 09
The Earth-facing side of the sun is blank--no sunspots.. Photo credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 19 Sept 2009

Spotless Days
Current Stretch: 18 days
2009 total: 211 days (81%)
Since 2004: 722 days
Typical Solar Min: 485 days
explanation | more info
Updated 19 Sept 2009

Far side of the Sun:
This holographic image reveals an active region on the far side of the sun. It is located at latitude 30-deg south, making it a probable member of Solar Cycle 24. Image credit: Global Oscillation Network Group
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 6.7 nT
Bz: 3.7 nT south
explanation | more data
Updated: Today at 2345 UT
Coronal Holes:
There are no coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Sep 20 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 Sep 20 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
September 20, 2009

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


SHUTTLE FERRY ALERT: Today, space shuttle Discovery is flying across the United States on the back of a 747 airliner. The pair took off from California's Edwards Air Force Base at the crack of dawn on Sunday and they are expected to reach the Kennedy Space Center in Florida sometime on Monday. Intermediate stops include Amarillo, Texas, for refueling, and Shreveport, Louisiana, for overnight rest. Sky watchers along the flight path should be alert for the shuttle ferry.


images: from Joel Warren of Amarillo, Texas;

SATURDAY NIGHT LIGHT SHOW: The phones started ringing around 7:30 pm EDT on Saturday night, Sept. 19th. All along the US Atlantic seaboard, police stations and news desks received reports of strange lights in the sky. John A. Blackwell of Exeter, New Hampshire, snapped this picture of the phenomenon:

"It was an impressive display," says Blackwell. "To the naked eye, it was visible for about a minute."

It looks like a passing comet or a giant, luminous amoeba. But this was pure rocket science. The cloud was created by a Black Brant XII sounding rocket launched from NASA's Wallops Flight Facility in Virginia. The rocket released a cloud of electrically-charged aerosols near the top of Earth's atmosphere to investigate the formation of noctilucent clouds or "NLCs." Mysterious NLCs form naturally around Earth's poles during the months of northern summer. On this September evening, researchers decided to see if they could create an artificial NLC at mid-latitudes; it seems to have worked.

Ground-based cameras and radars along the Atlantic coast monitored the experiment while the STPSat-1 satellite watched from Earth orbit. Principal investigators at the Naval Research Lab hope the data will reveal much about the microphysics of noctilucent clouds and the possible role of rockets in creating them.

more images: from Neil Winston of Lusby, Maryland; from Geoff Chester of Alexandria, Virginia; from Greg Piepol near Manassas, Virginia; from Tom McIntyre of Central Park, New York;

APPROACHING SUNSPOT: NASA's STEREO-B spacecraft stationed over the sun's eastern limb is monitoring an active region not yet visible from Earth. STEREO's extreme ultraviolet telescope captured this image on Sept. 19th:

The tangle of hot, magnetized plasma circled above almost certainly overlies a large new-cycle sunspot. We'll soon find out. The sun's rotation is turning the active region toward Earth and it could pop over the sun's eastern limb as early as Sept. 21st. Readers with solar telescopes are encouraged to monitor developments.

Sept. 2009 Aurora Gallery
[previous Septembers: 2008, 2007, 2006, 2005, 2004, 2002, 2001]

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 September 20, 2009 there were 1073 potentially hazardous asteroids.
Sept. 2009 Earth-asteroid encounters:
Miss Distance
2009 QC35
Sept. 2
2.9 LD
35 m
2009 RY3
Sept. 11
1.9 LD
50 m
2009 RR
Sept. 16
2.8 LD
33 m
2009 RG2
Sept. 21
9.1 LD
31 m
2009 HD21
Sept. 29
22.9 LD
1.0 km
1998 FW4
Sept. 29
8.6 LD
550 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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