When is the best time to see auroras? Where is the best place to go? And how do you photograph them? These questions and more are answered in a new book, Northern Lights - a Guide, by Pal Brekke & Fredrik Broms. | | | "HUGE ASTEROID" HYPE: Major news outlets are reporting the close approach of a "huge asteroid" to Earth on February 17-18. 2000 EM26 is about as wide as 2 football fields and it is flying past our planet 2 million miles away at 27,000 mph. It's all true. It's also all hype. This asteroid is little different than half-a-dozen other space rocks that have already whizzed passed Earth at similar distances in February, including one, 2006 DP14, that is almost 4 times larger. The sudden attention to 2000 EM26 is disproportionate to its actual uniqueness or potential impact. For a real close encounter, click here. 'RADIOACTIVE' ERUPTION: On Feb. 17th at approximately 04:50 UT, a magnetic filament erupted from the sun's western limb. NASA's Solar Dynamics Observatory captured this high-resolution image of the blast: Because of its location on the sun's western limb, the eruption did not send a CME toward Earth. However, there was an effect on our planet: Shortwave radio loudspeakers roared with static, an event called a Type II radio burst. Here's how it works: The explosion sent shock waves rippling through the sun's atmosphere. Those shock waves, in turn, triggered plasma instabilities in the solar corona that emit strong radio emissions. The static-y "roar" of the explosion was picked up by solar observatories and ham radio stations across the dayside of our planet. Based on the sweep of radio frequencies from 20 MHz to 500 MHz, analysts estimate a shock velocity of 776 km/s or 1.7 million mph. That may sound fast, but it is typical for this type of eruption. Solar flare alerts: text, voice Realtime Space Weather Photo Gallery HAPPY VALENTINE'S DAY FROM THE STRATOSPHERE: Helium is not free. That's why the student scientists of Earth to Sky Calculus occasionally fly commercial payloads onboard their suborbital research balloons. The profits fund space weather experiments in the stratosphere. On Feb. 11th, the team flew a batch of Valentine's Cards to the edge of space. Spaceweather reader Shiree Schade was one of the customers: "Best Valentine's card...EVER!" she says. "Not only will my valentine cherish the image, but I can't wait to start bragging to my friends that I'VE been to the stratosphere." The student group makes regular flights to the stratosphere to measure radiation and ozone during periods of stormy space weather. If you would like to support their work with, say, a birthday card or Mother's Day greeting, contact Dr. Tony Phillips to book passage. The cost is only $49.95. Realtime Space Weather Photo Gallery Realtime Aurora Photo Gallery Realtime Comet Photo Gallery Every night, a network of NASA all-sky cameras scans the skies above the United States for meteoritic fireballs. Automated software maintained by NASA's Meteoroid Environment Office calculates their orbits, velocity, penetration depth in Earth's atmosphere and many other characteristics. Daily results are presented here on Spaceweather.com. On Feb. 17, 2014, the network reported 11 fireballs. (11 sporadics)
In this diagram of the inner solar system, all of the fireball orbits intersect at a single point--Earth. The orbits are color-coded by velocity, from slow (red) to fast (blue). [Larger image] [movies] On Feb. 16, 2014, the network reported 0 fireballs. (winter weather) On Feb. 15, 2014, the network reported 0 fireballs. (winter weather) 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 18, 2014 there were potentially hazardous asteroids. 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. | The official U.S. government space weather bureau | | The first place to look for information about sundogs, pillars, rainbows and related phenomena. | | Researchers call it a "Hubble for the sun." SDO is the most advanced solar observatory ever. | | 3D views of the sun from NASA's Solar and Terrestrial Relations Observatory | | Realtime and archival images of the Sun from SOHO. | | from the NOAA Space Environment Center | | the underlying science of space weather | |