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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 311.4 km/sec
density: 3.6 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Apr28
24-hr: A0
2340 UT Apr28
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 28 Apr 09
A sunspot is struggling to emerge at the circled location. The magnetic polarity of the proto-sunspot identifies it as a member of old Solar Cycle 23. Credit: SOHO/MDI

more images: from Robert Arnold of Isle of Skye, Scotland; from Pavol Rapavy of Rimavska Sobota, Slovakia
Sunspot number: 0
What is the sunspot number?
Updated 27 Apr 2009

NEW: Spotless Days
Current Stretch: 6 days
2009 total: 103 days (88%)
Since 2004: 614 days
Typical Solar Min: 485 days
explanation | more info
Updated 27 Apr 2009

Far side of the Sun:
This holographic image reveals no large 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: 1.6 nT
Bz: 0.7 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
A new coronal hole is emerging over the sun's eastern limb. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Apr 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 Apr 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
April 28, 2009

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


CONJUNCTION IN MOTION: You've seen the snapshots, now watch the movie! Dale Ireland of Silverdale Washington spent two hours photographing Sunday night's conjunction of the Moon, Mercury and Pleiades, and he has created a time-lapse video of the trio setting behind the Olympic mountains. Chose a format, Windows media (0.7 MB) or Quicktime (1 MB), and enjoy the show.

BRIGHT EARTHSHINE: According to NASA-funded research, the best time to see Earthshine is now. Sunlight reflected from Earth onto the Moon is most intense during northern spring. Indeed, "the Earthshine was very bright in last night's 2.6-day-old Moon," says photographer Tamas Ladanyi of Hungary:

"I took the picture using a Zeiss 80/1200 refractor and a Canon 450D," he says. "Note the nice bluish colors" in the reflected glow of our blue planet.

The seasonal variation was discovered by the astronomers of Project Earthshine. Years of precise measurements showed that Earthshine in April and May is about 10% brighter than average. Earth's reflectivity is dominated by clouds, and it turns out that our planet is cloudiest and thus most reflective at this time of year. Reference: "Earthshine Observations of the Earth's Reflectance," by Goode et al, Geophysical Research Letters, Vol. 28, no. 9 (May 1, 2001), pp 1,671-1,674.

Readers, tonight you can find the crescent Moon hanging high in the western sky after sunset. Go outside and see Earthshine at its best: sky map.

NORTHERN LIGHTS VS MIDNIGHT SUN: At this time of year, night doesn't fall around the Arctic Circle until almost midnight. The window of darkness for auroras is shrinking as summer approaches. Nevertheless, "we saw some beautiful Northern Lights over the weekend," reports Sylvain Serre, who sends this April 25th picture from the outskirts of Salluit, an Inuit village in Nunavik, Canada:

Photo details: Canon EOS 30D, 10mm, f 3.5, 800 ISO, 15 sec

"On Saturday night, some friends and I decided to go out to take a few pictures," says Serre. "The sky was not very dark at 11:00 pm, but the Northern Lights came anyway. They were beautiful with a lot of movement over our heads."

More auroras are due on May 6th or 7th when a solar wind stream is due to hit Earth. Northern Lights vs. Midnight Sun--which will prevail? Stay tuned!

April 2009 Aurora Gallery
[previous Aprils: 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 28, 2009 there were 1053 potentially hazardous asteroids.
April 2009 Earth-asteroid encounters:
Miss Distance
2009 FU30
Apr. 2
8.8 LD
44 m
2004 VC
Apr. 3
51.3 LD
785 m
2002 EB3
Apr. 10
41.3 LD
1.3 km
2003 SG170
Apr. 19
57.7 LD
1.2 km
2009 HF21
Apr. 21
7.4 LD
27 m
2009 HJ21
Apr. 23
1.3 LD
14 m
2009 FJ30
Apr. 24
9.7 LD
130 m
2001 VG5
Apr. 26
58.5 LD
2.1 km
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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