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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 450.6 km/sec
density: 7.0 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Feb21
24-hr: A0
2340 UT Feb21
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 20 Feb 09
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 20 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= 1 quiet
24-hr max: Kp= 1
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 7.6 nT
Bz: 3.4 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on Feb. 21st. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Feb 21 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 21 2201 UTC
0-24 hr
24-48 hr
15 %
05 %
05 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
10 %
10 %
01 %
01 %
01 %
What's up in Space
February 21, 2009

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


AURORA WATCH: Arctic sky watchers should be alert for Northern Lights tonight. A solar wind stream is heading for Earth, and NOAA forecasters estimate a 30% chance of high-latitude geomagnetic activity when it arrives sometime during the next 24 hours: gallery.

THE GREEN COMET COMETH: From remote Portal, Arizona, astrophotographer Jack Newton reports: "Comet Lulin has brightened considerably and is now an easy naked eye object in dark, country skies." He photographed it using a Meade 14" HyperStar and sends this 16-minute exposure:

Comet Lulin's vivid green atmosphere is about three times as wide as the planet Jupiter, and its dusty tail stretches more than 1.5 million km into space. The comet is so big that "it no longer completely fits in my telescope's field of view," says Newton.

On Feb. 24th, Comet Lulin will swing past Earth only 38 million miles away. Got clouds? No problem. The Coca-Cola Space Science Center in Columbus, Georgia, plans to webcast the encounter. "We're going to transmit the view through our observatory's 16-inch Schmidt-Cassegrain telescope," says astronomy professor Rosa Williams of Columbus State University. "The webcast begins at 11:30 EST on Monday, Feb. 23rd and will continue until 5 a.m. EST on Tuesday the 24th." Tune in!

UPDATED: Comet Lulin Photo Gallery
[Comet Hunter Telescope] [Sky maps: Feb. 18, 19, 20]

SATELLITE DEBRIS UPDATE: US Strategic Command has identified a new batch of fragments from the Feb. 10th satellite collision over northern Siberia. "The count is now at 49 pieces for Iridium 33 and 85 for Kosmos 2251," says Canadian satellite tracker Daniel Deak, who has prepared some 3D maps of the debris for readers of Click on the image to view a snapshot of Iridium fragments on Feb 20th:

A similar map traces the Kosmos debris.

Observations: Both satellites are now smeared all the way around Earth; the original orbits are completely populated with fragments. Furthermore, for reasons not fully understood, Kosmos is more widely scattered than Iridium.

"The Kosmos debris ranges in altitude from 260 to 1450 km, so some of the pieces now reach lower than the 350-km orbit of the ISS," points out Deak. "For the Iridium debris, the fragments are confined to orbits between 687 and 1127 km."

This doesn't mean the ISS is in immediate peril. Most of the Kosmos scatter occurs over Antarctic latitudes. For comparison, the ISS stays within 51.6 degrees of Earth's equator, so the dangers are slight. The situation could change, however, as more fragments are identified and their spread increases. Stay tuned for updates.

A complete set of debris maps: #1, #2, #3, #4, #5

February 2009 Aurora Gallery
[Previous Februaries: 2008, 2007, 2006, 2004, 2003, 2002]

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 21, 2009 there were 1028 potentially hazardous asteroids.
Feb. 2009 Earth-asteroid encounters:
Miss Distance
2009 BK58
Feb. 2
1.7 LD
30 m
2009 BG81
Feb. 2
4.4 LD
12 m
2009 CC2
Feb. 2
0.5 LD
12 m
2009 BW2
Feb. 5
8.4 LD
40 m
2009 CP
Feb. 8
7.7 LD
20 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
2009 CV
Feb. 23
4.8 LD
62 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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