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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 368.3 km/sec
density: 13.4 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Feb04
24-hr: A0
2340 UT Feb04
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 04 Feb 09
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 04 Feb. 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= 4 unsettled
24-hr max: Kp= 4
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 6.4 nT
Bz: 5.3 nT south
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 Feb 04 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 Feb 04 2201 UTC
0-24 hr
24-48 hr
05 %
01 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
10 %
05 %
01 %
01 %
01 %
01 %
What's up in Space
February 4, 2009

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


IRANIAN SATELLITE: Iran's first home-grown satellite is now in Earth orbit. Named Omid (Farsi for "hope"), the diminutive comsat was launched on Feb. 2nd atop a Safir-2 rocket. Sky watchers in Europe have sighted both the satellite and the launch vehicle streaking separately across the night sky. The objects are dim (4th to 7th magnitude) but potentially visible to the unaided eye from dark-sky sites. Check the Simple Satellite Tracker for flyby times.

UPDATE: Enough orbits have passed to make an initial estimate of Omid's decay rate. The satellite and its rocket should reenter Earth's atmosphere in June-July 2009.

ISS FLYBYS: Here's something you can definitely see: the International Space Station. The behemoth spaceship spans 93 meters, masses 227,000 kg and shines about as brightly as the planet Venus. For comparison, astronomy professor Jimmy Westlake photographed the space station streaking past Venus last night over Stagecoach, Colorado:

"It was very cool," says Westlake. "The streak shows how far the ISS moved during the 35 second exposure. I used a Fuji Finepix S2
digital camera and a 35 mm Nikkor lens."

North Americans should be alert for more scenes like this in the evenings ahead. The ISS is making a series of Venus-skimming twilight passes over the United States and Canada this week: flyby times.

more images: from Chris Peterson of Guffey, Colorado; from Val Germann of Columbia, Missouri; from Babak Tafreshi of Giessen, Germany.

DISCONNECTED TAIL: This morning, February 4th, a team of Italian astronomers was photographing Comet Lulin through a remotely-controlled telescope in New Mexico when "we were lucky enough to observe an intriguing phenomenon in the comet's tail," reports team leader Ernesto Guido. "Our images clearly show a disconnection event in progress. While we were looking, part of the comet's plasma tail was bring torn away."

Photo credit: Ernesto Guido, Giovanni Sostero & Paul Camilleri [more]

Guido and colleagues believe the event was caused by a magnetic disturbance in the solar wind hitting the comet. It's a plausible hypothesis. Mini-magnetic storms in comet tails have been observed before--most famously in 2007 when NASA's STEREO spacecraft watched a CME crash into Comet Encke. Encke lost its tail in dramatic fashion, much as Comet Lulin did this morning.

Comet Lulin is approaching Earth for a Feb. 24th close encounter. This means the comet's tail--and its storms--are getting easier to see every night. Astronomers, ready your telescopes!

Comet Lulin Photo Gallery
[3D orbit] [sky map] [ephemeris]

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 February 4, 2009 there were 1022 potentially hazardous asteroids.
Feb. 2009 Earth-asteroid encounters:
Miss Distance
2009 BK58
Feb. 2
1.7 LD
30 m
2009 BW2
Feb. 5
8.4 LD
40 m
2009 BE58
Feb. 10
8.6 LD
225 m
2006 AS2
Feb. 10
9.2 LD
370 m
2009 BL58
Feb. 11
4.8 LD
55 m
1999 AQ10
Feb. 18
4.4 LD
390 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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