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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 306.2 km/sec
density: 2.7 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Apr02
24-hr: A0
2340 UT Apr02
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 02 Apr 09
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 01 Apr 2009

NEW: Spotless Days
Current Stretch: 25 days
2009 total: 79 days (87%)
Since 2004: 590 days
Typical Solar Min: 485 days
explanation | more info
Updated 01 Apr 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: 4.3 nT
Bz: 0.8 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 April 8th or 9th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Apr 02 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 Apr 02 2201 UTC
0-24 hr
24-48 hr
10 %
10 %
05 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
10 %
10 %
01 %
01 %
What's up in Space
April 2, 2009

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


DEEP SOLAR MINIMUM: How low can it go? According to NASA, the sun is plunging into the deepest solar minimum in a century. A new spotless days counter on is keeping track of the record-setting quiet. Look for it beneath the Daily Sun.

SPACE STATION ECHO: On Tuesday night, the International Space Station flew over the southwestern United States where it was "pinged" by the powerful USAF Space Surveillance Radar. Ham radio operator Stan Nelson of Roswell, New Mexico, recorded the 217 MHz echo. Click on the dynamic spectrum to listen:

ISS Radar Echo on March 31st: audio | spectrum

What was that you just heard? The constant tone is the CW (continuous wave) signal broadcast skyward by the radar. The descending tone is the radar's doppler-shifted reflection from the ISS.

"A friend and I were observing last night using my Meade telescope when he mentioned that the ISS was due to make a flyby," says Nelson. "I quickly set up my radar monitoring system to record the audio. We then watched the ISS glide through the starry sky east of Roswell as the loudspeaker played the radar signal--very enjoyable! The sound is reminiscent of a space shuttle reflection I captured a few years back."

The ISS is making a series of bright flybys over North America this week. It's fun to watch even without a soundtrack. Check the Simple Satellite Tracker for viewing times.

NEW VERB: There's a new verb in Alaska: "to ash." It's like "to snow," only grayer and more sulfurous. Residents downwind of Mt. Redoubt are using it like this: "We don't run our ski lifts when it ashes because it damages the electric motors," says Michelle Cosper of the Alyeska Resort near Girdwood. It's been ashing a lot lately as Mt. Redoubt has erupted more than 19 times since March 22nd. "The ash has created a moonscape with all the highlights of gray," she says.

The resemblance to moondust is more than superficial. Consider the following: Volcanic ash is gray, abrasive, can be dangerous to breathe and easily electrified. Moondust is gray, abrasive, can be dangerous to breathe and easily electrified. Indeed, Alaskans are getting a taste of life on the Moon.

"The ski area may or may not be open tomorrow, depending on ash fall," adds Cosper. "My throat is sore and stingy, and it smells vaguely like sulfur. They say not to walk your dogs or go outside unnecessarily. Even local newscasters are wearing face masks."

To ash or not to ash? According to the Alaska Volcano Observatory, another eruption is imminent.

VOLCANIC CLOUD TRACKING: The GOME-2 (Global Ozone Monitoring Experiment) sensor onboard Europe's MetOp-A satellite is tracking Mt. Redoubt's sulfur dioxide clouds. Follow the red pixels in this 7-day animation and be alert for fantastic sunsets when the clouds pass over your area.

March 2009 Aurora Gallery
[previous Marches: 2008, 2007, 2006, 2005, 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 April 2, 2009 there were 1049 potentially hazardous asteroids.
March 2009 Earth-asteroid encounters:
Miss Distance
2009 DS43
Mar. 1
6.9 LD
32 m
2009 DD45
Mar. 2
0.2 LD
35 m
2009 DN4
Mar. 3
8.1 LD
27 m
2009 EA
Mar. 4
7.4 LD
24 m
2009 EW
Mar. 6
0.9 LD
23 m
161989 Cacus
Mar. 7
70.5 LD
1.7 km
2009 EH1
Mar. 8
1.6 LD
12 m
2009 ET
Mar. 9
9.5 LD
15 m
2009 DV43
Mar. 10
8.5 LD
80 m
2009 EU
Mar. 11
3.5 LD
21 m
1998 OR2
Mar. 12
69.8 LD
3.3 km
2009 DR3
Mar. 14
7.2 LD
225 m
2009 FR
Mar. 16
6.7 LD
22 m
2009 FJ
Mar. 16
4.9 LD
46 m
2009 FW4
Mar. 17
2.8 LD
53 m
2009 FH
Mar. 18
0.2 LD
21 m
2009 FK
Mar. 19
1.0 LD
9 m
2009 DO111
Mar. 20
1.2 LD
117 m
2009 FX4
Mar. 23
6.1 LD
37 m
2009 FD
Mar. 27
1.6 LD
160 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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