You are viewing the page for Apr. 11, 2008
  Select another date:
<<back forward>>
SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
SPACE WEATHER
Current conditions
Solar wind
speed: 569.6 km/sec
density: 1.0 protons/cm3
explanation | more data
Updated: Today at 2255 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Apr11
24-hr: A0
2245 UT Apr11
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 11 Apr 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 10 Apr 2008
Far side of the Sun:
This holographic image reveals no sunspots on the farside of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 2
quiet
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 4.3 nT
Bz: 2.5 nT south
explanation | more data
Updated: Today at 2256 UT
Coronal Holes:
There are no well-organized coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2008 Apr 11 2203 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
01 %
01 %
CLASS X
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: 2008 Apr 11 2203 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
20 %
MINOR
10 %
10 %
SEVERE
01 %
01 %
What's up in Space
April 11, 2008
Where's Saturn? Is that a UFO--or the ISS? What's the name of that star? Get the answers from mySKY--a fun new astronomy helper from Meade.   mySKY

MOON & MARS: When the sun sets tonight, go outside and look west. See the Moon? The red "star" right beside it is the planet Mars. The two are gathered beautifully close together in the heart of the constellation Gemini: sky map.

MOONDUST IN THE WIND: Unlike Earth, the Moon has no magnetic field to ward off charged particles from the Sun. Solar wind blows directly onto the lunar surface. Researchers have long suspected that electrons in the solar wind become embedded in moondust, causing the dust to "charge up" and giving the Moon a very bad case of static cling. (continued below)


Image credit: J. Halekas, G. Delory (U.C. Berkeley), B. Farrell, T. Stubbs (GSFC)

Strange things can happen when moondust gathers charge. For one, the dust might rise up and, propelled by electrostatic repulsion, rush in a diaphanous wind across the lunar surface. Imagine, dust storms on an airless world with no weather!

But it could be even stranger than that. NASA researchers have discovered that moondust peppered with solar wind electrons gain not a negative but a positive charge. This unexpected and counterintuitive reaction makes it hard to predict what is really happening to dust on moon. Get the full story from Science@NASA.

3D MOON OF MARS: Grab your 3D glasses. Two weeks ago, NASA's Mars Reconnaisance Orbiter (MRO) targeted martian moon Phobos and took a pair of high-resolution pictures. Mission scientists have combined them to make a startling red-blue anaglyph. Glasses on? Behold.

The 2D view is nearly as good:

Long ago, something struck Phobos and almost shattered the tiny moon. The scar of that impact, 9km-wide Stickney crater, is located at the top of the image. Color filters in MRO's camera reveal a blue splash of material around Stickney's rim. What is it? No one knows. Equally striking are Phobos' many long grooves and crater chains. Although these seem to radiate from Stickney, recent studies show that most are not related to the crater. Instead they come from the planet below; when asteroids hit Mars, debris flies up and scores Phobos. The grooves seem to emerge from Stickney only because the crater faces Mars. Finally, note the bright features lining inner slopes of Stickney. These are thought to be landslides--on a moon where the pull of gravity is only 0.001 g!

Visit the Mars Reconnaissance Orbiter home page for more information,


March 2008 Aurora Gallery
[Aurora Alerts] [Night-sky Cameras]

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. [comment]
On April 11, 2008 there were 946 potentially hazardous asteroids.
April 2008 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2008 FH5
Apr. 2
7.6 LD
20
17 m
2001 QO142
Apr. 6
34 LD
17
685 m
2008 GF1
Apr. 7
0.8 LD
18
10 m
2005 BE2
Apr. 10
62 LD
18
1.0 km
2005 NB7
Apr. 17
16 LD
16
705 m
2008 FU6
Apr. 22
62 LD
16
1.4 km
2005 TB
Apr. 28
47 LD
18
1.3 km
2001 DQ8
Apr. 30
74 LD
17
1.1 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 bureau for real-time monitoring of solar and geophysical events, research in solar-terrestrial physics, and forecasting solar and geophysical disturbances.
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.
Daily Sunspot Summaries
  From the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
  more links...
©2008, SpaceWeather.com -- This site is penned daily by Dr. Tony Phillips.
©2019 Spaceweather.com. All rights reserved.