~ Space Weather Update~ RUSSIAN METEOR UPDATE:

RUSSIAN METEOR UPDATE: On Friday, February 15th at 9:30 am local time in Russia, a small asteroid struck the atmosphere over the city of Chelyabinsk and exploded. According to reports from news organizations and Russian authorities, as many as 1000 people received minor injuries from the shock wave. This is the most energetic recorded meteor strike since the Tunguska impact of 1908.

NASA scientists have conducted a preliminary analysis of the event. "Here is what we know so far," says Bill Cooke, head of NASA's Meteoroid Environment Office. "The asteroid was about 15 meters in diameter and weighed approximately 7000 metric tons. It struck Earth's atmosphere at 40,000 mph (18 km/s) and broke apart about 12 to 15 miles (20 to 25 km) above Earth's surface. The energy of the resulting explosion was in the vicinity of 300 kilotons of TNT." (continued below)

"A shock wave propagated down and struck the city below, causing large numbers of windows to break, some walls to collapse, and minor damage throughout the city," he continued. "When you hear about injuries, those are undoubtedly due to the effects of the shock wave, not due to fragments striking the ground. There are undoubtedly fragments on the ground, but as of this time we know of no recovered fragments that we can verify."

Videos of the event may be found here and here. In many of the videos you can hear the sound of windows shattering as the meteor's loud shock wave reaches the ground. Onlookers cry out in Russian as alarms and sirens sound in the background. This pair of wide-angle gif animations is also worth watching: #1, #2.

It is natural to wonder if this event has any connection to today's record-setting flyby of asteroid 2012 DA14. Paul Chodas of the Near Earth Object Program at JPL says no. "The Russian fireball is not related to 2012 DA14 in any way. It's an incredible coincidence that we have had these two rare events in one day."

Stay tuned for updates!

ASTEROID FLYBY: At 2:25 p.m. EST (19:25 UTC) on Friday, Feb. 15th, asteroid 2012 DA14 will fly past Earth only 17,200 miles above our planet's surface. This will put it well inside the orbit of geosynchronous satellites, closer than any asteroid of the same size has come since regular sky surveys began in the 1990s. Researchers speculate that Earth's gravity might even cause seismic activity on the 50m-wide space rock. Click to view a computer simulation of the flyby, courtesy of NASA:

During the hours around closest approach, the asteroid will brighten until it resembles a star of 8th magnitude. Theoretically, that’s an easy target for backyard telescopes. The problem is speed. The asteroid will be racing across the sky, moving almost a full degree (or twice the width of a full Moon) every minute. That’s going to be hard to track. Only the most experienced amateur astronomers are likely to succeed. For the rest of us, NASA will broadcast the asteroid's flyby on NASA TV.

Asteroid 2012 DA14 is about the same size as previous asteroids responsible for the Meteor Crater in Arizona and the Tunguska Event in Siberia. Unlike those objects, however, 2012 DA14 will not hit Earth. Even if seismic activity breaks the asteroid apart, there is no danger; the fragments would continue along the same non-intersecting path as the original asteroid.

Realtime Space Weather Photo Gallery

VALENTINE'S DAY MAGNETIC STORM: Valentine's Day in Scandinavia began with a magnetic storm. Rob Stammes of the Polar Light Center in Lofoten, Norway, reports: "Our instruments recorded 2^o swings in the local magnetic field, which induced strong electrical currents in the ground outside our lab." The needles on his chart recorder were swinging wildly:

"Overhead we saw some fantastic auroras," he adds.

The storm was caused by a region of south-pointing magnetism in the solar wind that wafted past Earth during the early hours of Feb. 14th. The solar wind's south-pointing magnetic field partially canceled Earth's north-pointing magnetic field, opening a crack in our planet's magnetosphere. Solar wind poured in to fuel the storm.

Browse the realtime gallery for images of some sweet auroras on Valentine's day. Aurora alerts: text, voice.

Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES

Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 1 quiet
explanation | more data

Interplanetary Mag. Field
B_total: 4.0 nT
B_z: 2.2 nT north
explanation | more data
Updated: Today at 2156 UT

Coronal Holes: 15 Feb 13

There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.