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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: 440.5 km/sec
density: 2.0 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: A2
1850 UT Jul16
24-hr: B2
0100 UT Jul16
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 16 July 07
Sunspots 963 and 964 are decaying and pose little threat for strong solar flares. Credit: SOHO/MDI
Sunspot number: 41
What is the sunspot number?
Updated 15 July 2007
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= 1 quiet
24-hr max: Kp= 2
quiet
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Updated: 2007 Jul 16 2057 UT
Interplanetary Mag. Field
Btotal: 3.2 nT
Bz: 2.2 nT south
explanation | more data
Updated:Today at 2246 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on or about July 20th. Credit: SOHO Extreme Ultraviolet Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2007 Jul 16 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: 2007 Jul 16 2203 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
10 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
What's up in Space
July 16, 2007
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.

CELESTIAL GATHERING: When the sun goes down tonight step outside and look west. You'll see Venus, Saturn and the bright star Regulus forming a triangle with the crescent Moon inside. A backyard telescope pointed at Venus reveals it to be a crescent, too, almost as slender as the Moon. Take a look: sky map.

images: from John Hacker of Carl Junction, Missouri; from Michael Bromley in the Sahara Desert east of Dahra, Libya.

WEEKEND AURORAS: On Saturday night, July 14th, Tony Wilder of Chippewa Falls, Wisconsin, thought he saw a hint of green in the northern sky. He wasn't imagining things. A 28-second exposure with his Canon 30D (ISO 1600) revealed a beautiful curtain of aurora borealis over nearby Lake Wissota:

"What a treat to see the Northern Lights again," he says. "The sky was glowing mildly until 1 o'clock in the morning when clouds blocked my view."

The cause of the display was a solar wind stream hitting Earth and shaking our planet's magnetic field. The reverberations registered 6 on the 0-to-9 K-index scale of geomagnetic storms and produced auroras over both ends of our planet. While Tony Wilder was snapping pictures in Wisconsin, scientist Chantal Steyn took this picture from Queen Maud Land, Antarctica. "We waited almost a month for some auroras, and finally!" she says. Visit the gallery for more.

LOOKING AHEAD: Another solar wind stream is due on July 20th. High latitude sky watchers should be alert for auroras.

RED-TAILED COMET: "The atmosphere of Comet LINEAR VZ13 is green," reports Italian astronomer Paolo Candy, "but its jet tail is red." He took this picture, a 14-minute exposure through an 8-inch telescope, on July 15th:

The green tint comes from gaseous cyanogen and diatomic carbon in the comet's atmosphere. Both substances glow green when exposed to sunlight in the near-vacuum of space. The origin of red in the tail is less certain. The tail is essentially a jet of dust spewing out of the comet's nucleus. Normally, cometery dust tails are yellow-white, the color of reflected sunlight. But the material in this tail seems to reflect a little extra red--much like another notable red-tailed comet.

Amateur astronomers, this 8th-magnitude comet is an easy target for backyard telescopes. Look for it after sunset near the handle of the Big Dipper: sky map. [ephemeris] [3D orbit]

more images: from Frank Freestar8n of Hudson Valley, NY.


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 16, 2007 there were 874 potentially hazardous asteroids.
July 2007 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2007 FV42
July 2
53 LD
15
1.2 km
2007 MB4
July 4
7.6 LD
16
130 m
2007 DT103
July 29
9.3 LD
15
550 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 Environment 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...
©2007, SpaceWeather.com -- This site is penned daily by Dr. Tony Phillips.
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