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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 341.3 km/sec
density: 4.4 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: A1
2245 UT Sep28
24-hr: A2
1415 UT Sep28
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 28 Sept. 09
Sunspot 1026 is fading away and may be gone by the end of the day. Photo credit: SOHO/MDI
Sunspot number: 11
What is the sunspot number?
Updated 27 Sept 2009

Spotless Days
Current Stretch: 0 days
2009 total: 212 days (79%)
Since 2004: 723 days
Typical Solar Min: 485 days
explanation | more info
Updated 27 Sept 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= 2 quiet
24-hr max: Kp= 4
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 4.0 nT
Bz: 3.2 nT north
explanation | more data
Updated: Today at 2345 UT
Coronal Holes:
There are no large coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Sep 28 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 28 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 28, 2009

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


JUST FOUR MORE INCHES... In 1976, NASA's Viking 2 lander dug into the soil of Mars in search of water and came up dry. NASA has just learned that Viking 2 might have succeeded if it had dug only 4 inches deeper. Meteorites hitting the Red Planet in 2008 and 2009 have exposed subsurface deposits of ice in the general area where Viking 2 landed. According to pictures taken by the Mars Reconnaissance Orbiter, the ice is surprisingly close to the surface in easy reach of robotic landers or thirsty human explorers. Get the full story from Science@NASA.

PARABOLIC FLIGHT TO MARS: Today, Sept. 28th, high above the Netherlands, a Cessna Citation II filled with scientists will conduct a "parabolic flight to Mars." The aircraft will never leave Earth's atmosphere, but inside it will feel just like the Red Planet. "Our pilots will execute a series of parabolic maneuvers that precisely simulate Mars-gravity (0.38g)," says Sebastiaan de Vet of the University of Amsterdam. Here is a snapshot of a test flight on Sept. 23rd:

"The purpose of today's flight is to study avalances on Mars," de Vet explains. "The experiment looks like this."

"Avalanches might seem like simple processes, but the way gravity acts on crumbled material to make an avalanche is not fully understood," he says. "By experimenting with avalanches under Martian gravity, scientists hope to reconstruct how various landscapes on Mars might have been formed."

"Insights gained from these experiments (funded by the Netherlands Space Office) are not only valuable for research on Mars, but also for research on Earth. Avalanche behaviour is common in river systems and in steep mountainous areas where rock and snow can damage roads, villages and dams. Understanding the complex mechanisms of avalanches could lead to better forecasts or even prevention."

WEEKEND AURORAS: A solar wind stream buffeted Earth's magnetosphere on Sept. 26th. It was a gentle hit, but enough to spark a bright display of arctic lights. Robert Postma sends this picture from the shores of Lake Myvatn, Iceland:

The pony-sized Icelandic horses in the foreground must have been mesmerized. "They stood still for the entire 30 second exposure," says Postma.

The solar wind stream that sparked the display is still flowing around Earth. Arctic observers should remain alert for Northern Lights.

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 28, 2009 there were 1076 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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