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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 317.4 km/sec
density: 0.3 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Oct24
24-hr: A0
2245 UT Oct24
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 24 Oct 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 23 Oct. 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= 0 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: 2.3 nT
Bz: 0.8 nT north
explanation | more data
Updated: Today at 2247 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on or about Oct. 28th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2008 Oct 24 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: 2008 Oct 24 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
October 24, 2008
BEHOLD THE SUN: Would you like to see fiery prominences and new-cycle sunspots with your own eyes? On sale now: Personal Solar Telescopes.  

AURORA FORECAST: A solar wind stream is heading for Earth and it could spark a geomagnetic storm when it arrives on Oct. 28th. Sky watchers around the Arctic Circle should be alert for auroras.

FLASHBACK: One year ago today, on Oct. 24, 2007, Comet 17P/Holmes shocked astronomers when it suddenly exploded, brightening a million-fold to naked-eye visibility. Within three days of the blast, the comet was bigger than Jupiter, and within three weeks it was larger than the sun itself. Spanish photographers Vicent Peris and José Luis Lamadrid recorded this view on Nov. 1, 2007, using little more than a 7-inch telescope:

What happened to Comet Holmes? Just-released observations by NASA's Spitzer Space Telescope define the mass and velocity of the explosion: "The energy of the blast was about 1014 joules and the total mass was of order 1010 kg," says Bill Reach of Caltech. In other words, Holmes exploded like 24 kilotons of TNT and ejected 10 million metric tons of dust and gas into space. These numbers fit a model favored by Reach in which a cavern of ice some hundred meters beneath the comet's crust changed phase, from amorphous to crystalline, releasing in transition enough heat to cause Holmes to blow its top.

Holmes has exploded twice in recorded history--in 1892 and 2007. Two caverns down, how many to go? No one knows. Browse the gallery for a preview of what the next blast might look like:

Comet Holmes Photo Gallery
[JPL press release] [Night Sky Cameras]

ASTEROID FLYBY: "At midnight on Oct. 23rd, I began my lonely vigil," says Dennis Simmons of Brisbane, Australia. "I was hunting for 2008 TT26, a 70-meter asteroid scheduled to pass less than a million miles from our home planet Earth. What I hadn't anticipated was the frantic pace set by the little space rock as it zoomed through my field of view!" He captured this movie using a 9-inch Celestron telescope and an SBIG ST7e CCD camera:

Click on the image for photo details

Although on the scale of asteroids 2008 TT26 is small, it is still a dangerous object, about twice as wide as the mystery-rock that caused the Tunguska event of 1908. Fortunately, 2008 TT26 was beyond the orbit of the Moon when it made its closest approach on Oct. 23rd.

"Later that morning," says Simmons, "having seen the animation, my wife humoured my efforts, thanking me for keeping watch on the fast approaching lump of rock while she had slept soundly, glad that somewhat was looking out for planet Earth!"

more images: from Leonid Elenin of Mayhill, New Mexico

2008 Orionid Meteor Gallery
[IMO meteor counts] [2006 Orionids]

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 October 24, 2008 there were 992 potentially hazardous asteroids.
Oct. 2008 Earth-asteroid encounters:
Miss Distance
2008 QS11
Oct. 2
11 LD
470 m
2008 SH148
Oct. 4
5.8 LD
26 m
2005 GN59
Oct. 6
20 LD
1.4 km
2008 TC3
Oct. 7
3 m
2008 TZ
Oct. 10
5.3 LD
37 m
1999 VP11
Oct. 16
72 LD
860 m
2001 UY4
Oct. 18
74 LD
1.1 km
Comet Barnard-Boattini
Oct. 21
75 LD
2008 UM1
Oct. 22
0.2 LD
2 m
2008 TT26
Oct. 23
3.6 LD
70 m
2000 EX106
Oct. 23
69 LD
1.1 km
2005 VN
Oct. 29
4.1 LD
116 m
2008 TX3
Nov. 1
9 LD
45 m
4179 Toutatis
Nov. 9
20 LD
3.8 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
  a one-stop hub for all things scientific
  more links...
©2008, -- This site is penned daily by Dr. Tony Phillips.
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