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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: 359.2 km/sec
density: 4.5 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Feb17
24-hr: A0
2340 UT Feb17
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 17 Feb 09
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 17 Feb. 2009
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
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: 3.1 nT
Bz: 1.2 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on or about Feb. 20th. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2009 Feb 17 2201 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: 2009 Feb 17 2201 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
10 %
10 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
What's up in Space
February 17, 2009

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

 

SOLAR ACTIVITY: There are no sunspots today, but that doesn't mean the sun is quiet. Astronomers are monitoring a lively prominence flying away from the southwestern limb of the sun. If you have a solar telescope, take a look.

COMET LULIN UPDATE: Comet Lulin is approaching Earth for a 38-million-mile close encounter on Feb. 24th. Veteran observer Mariano Ribas sends this report from Argentina: "Today at 4 a.m. in Buenos Aires, I observed the comet with my 90 mm refractor (25x). It is much brighter than it was just a few nights ago. I estimate the magnitude at +5.6. If this brightening continues, Lulin could reach magnitude +5.0 or even brighter during its closest approach next week."

Lulin has brightened so much, telescopic amplification is no longer needed to photograph it. Using an off-the-shelf digital camera, Alex Roca of Hortoneda, Spain, caught the comet passing 4th-magnitude star theta Virginis on Feb. 17th:

"I mounted the camera, a Nikon D40, on the back of my telescope to track the stars," he says. "Otherwise, the telescope played no part in this 10 minute exposure."

Comet Lulin Photo Gallery
[Comet Hunter Telescope] [NASA's story] [ephemeris]

FIREBALL MANIA: Runners in Sunday's Austin marathon were astonished when a brilliant fireball raced across the Texas sky in broad daylight. The extremely-bright meteor descended at 11 am CST on Feb. 15th less than a day after the FAA reportedly warned U.S. pilots to watch for "falling space debris" from the recent satellite collision between Iridium 33 and Kosmos 2251. Click on the image to launch a News 8 Austin video:


Click to view fireball video

What you just saw was not satellite debris. The high speed of the fireball in the News 8 video is typical of a natural meteoroid hitting Earth's atmosphere at tens of km/s. Orbital debris, on the other hand, should crawl across the sky at a fraction of that speed. Astronomer Bill Cooke of NASA's Meteoroid Environment Office has reviewed the video and confirms "it's a natural meteor, definitely." According to his analysis, the source of the fireball was a meter-class asteroid traveling at about 20 km/s.

Fireball mania started on Friday the 13th, around 10 p.m. EST, when people in central Kentucky heard loud booms, felt their houses shake, and saw a fireball streaking through the sky: reports. "The world appeared to explode--in green!" said one eyewitness. Once again, this appears to be a natural event caused by a meteoroid. Iridium 33 and Kosmos 2251 collided at a speed of about 10 km/s or 22,000 mph. None of the surviving fragments should have been big enough to shake houses in Kentucky. Furthermore, US Space Command, which monitors objects in Earth orbit, has not announced a reentry over Kentucky on Feb. 13th.

Just hours before the Kentucky event, around 20:03 UT on Feb. 13th, multiple cameras in Italy recorded a fireball some 10 times brighter than a full Moon. Astronomer Diego Valeri sends this image from the town of Rieti:


Click to view fireball video (Note: DivX required)

Ferruccio Zanotti of Ferrara, Italy, recorded that same fireball and two others. Italian scientists are plotting the trajectory of the brightest fireball to estimate where it might have hit the ground; a meteorite hunt will soon be underway.

Although it is tempting to attribute the Kentucky and Italian fireballs to debris from the Feb. 10th collision of the Iridium 33 and Kosmos 2251 satellites, they seem to be meteoroids, not manmade objects.

Are we experiencing a "fireball shower?" Not necessarily. Meteoroids hit Earth every day. The daily fireballs they produce, however, are seldom reported: 70% streak over uninhabited ocean; half appear in glaring daylight; many are missed because people are asleep, at work, or not looking up. This current spate of fireballs could simply be a few ordinary, random meteoroids that have attracted extraordinary attention because of the recent satellite collision. The jury is still out.

Stay tuned for updates.


February 2009 Aurora Gallery
[Previous Februaries: 2008, 2007, 2006, 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 February 17, 2009 there were 1026 potentially hazardous asteroids.
Feb. 2009 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2009 BK58
Feb. 2
1.7 LD
17
30 m
2009 BG81
Feb. 2
4.4 LD
19
12 m
2009 CC2
Feb. 2
0.5 LD
17
12 m
2009 BW2
Feb. 5
8.4 LD
20
40 m
2009 CP
Feb. 8
7.7 LD
19
20 m
2009 BE58
Feb. 10
8.6 LD
16
225 m
2006 AS2
Feb. 10
9.2 LD
15
370 m
2009 BL58
Feb. 11
4.8 LD
17
55 m
1999 AQ10
Feb. 18
4.4 LD
13
390 m
2009 CV
Feb. 23
4.8 LD
18
62 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
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STEREO
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Daily Sunspot Summaries
  from the NOAA Space Environment Center
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  from the National Solar Data Analysis Center
Science Central
   
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