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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
SPACE WEATHER
Current conditions
Solar wind
speed: 467.3 km/sec
density: 0.7 protons/cm3
explanation | more data
Updated: Today at 2245 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Jul24
24-hr: A0
1350 UT Jul24
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 24 Jul 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 23 July 2008
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= 2 quiet
24-hr max: Kp= 4
unsettled
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: 1.9 nT
Bz: 0.7 nT north
explanation | more data
Updated: Today at 2246 UT
Coronal Holes:
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2008 Jul 24 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 Jul 24 2203 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
What's up in Space
July 24, 2008
AURORA ALERTS: Did you miss the Northern Lights of July 12th? Next time get a wake-up call from Space Weather PHONE.  

PLASMA BULLETS SPARK AURORAS: Researchers have discovered what causes brilliant outbursts of Northern Lights: Gigantic plasma bullets launched toward Earth by explosions 1/3rd of the way to the Moon. Get the full story from Science@NASA.

NLCs IN MOTION: The electric-blue tendrils of noctilucent clouds (NLCs) are undeniably lovely and a fine target for backyard photographers. But a still shot hardly does them justice. Click on the image, below, to set the clouds in motion:


Click to view a 2.5 MB time lapse movie

"The movie spans about two hours," says photographer Derick Rethans of Skien, Norway. "I set my camera to make an exposure every 30 seconds from 01:30 to 03:20 in the morning on Thursday, July 17th, 2008."

A similar movie submitted by Jan Lameer of Schermer Polder, the Netherlands, is a little less blue but equally mesmerizing: play it.

NLCs are most often seen from far northern places like Norway, but lately the clouds have been spreading south with sightings in the USA, Turkey and Iran. Sky watchers at all latitudes should be alert for these displays. Check the photo gallery for observing tips:

2008 Noctilucent Cloud Gallery
[Strange Clouds] [Sky Cameras]

MIDNIGHT SUN: Behold the midnight sun ... on Mars:

NASA's Phoenix lander took the picture just a few days ago. Although it was the middle of the night, the sun was still up and shining. Phoenix is located in the martian arctic--the best place to study icy soil--and there the summer sun does not set. An 11-day composite photo from Mars resembles time lapse pictures taken above the Arctic Circle on Earth.

Phoenix is solar-powered and it relies on constant sunlight for all its day-to-day operations. This means Phoenix will not live forever. Martian seasons are changing, and on September 1st (Earth time) the sun will set. At first it will just briefly graze the horizon, causing little trouble for Phoenix, but by April 3, 2009, the descending sun will disappear for good. Night and frigid cold will envelop the powerless lander for more than 3 months, probably bringing the mission to an end. On the other hand, NASA's Mars landers have proven remarkably tough; perhaps Phoenix will revive itself after the long night. No one knows. Meanwhile the digging continues.

BONUS--MIDNIGHT SHADOWS: As the arctic sun circles the martian sky, shadows twirl around the rocks at Phoenix's landing sight. Reader Stuart Atkinson of Kendal, England, combined three snapshots taken by Phoenix's stereo camera to create this animation he calls Midnight Shadows.

       
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 July 24, 2008 , there were 962 potentially hazardous asteroids.
July 2008 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2003 YE45
July 13
16.5 LD
15
1.4 km
2008 BT18
July 14
5.9 LD
13
1.0 km
2003 LC5
July 15
62 LD
16
1.4 km
2008 NP3
July 17
6.8 LD
18
85 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 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.
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