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. | | | THE CME HAS ARRIVED: As expected, a CME hit Earth's magnetic field on Jan. 9th (around 20:00 UTC or 3 p.m. EST). Although the initial impact was weaker than expected, geomagnetic storms could still develop as Earth passes through the CME's wake. NOAA forecasters are sticking by their prediction of a G3-class event on Jan. 9-10, which means high-latitude sky watchers should remain alert for auroras. Aurora alerts: text, voice. HUGE SUNSPOT, CHANCE OF FLARES: The source of the incoming CME is AR1944, one of the largest sunspots of the current solar cycle. The active region sprawls across more than 200,000 km of solar terrain and contains dozens of dark cores. The largest could swallow Earth three times over. AR1944 is circled in this Jan. 9th snapshot from NASA's Solar Dynamics Observatory: As the image shows, the sunspot is almost directly facing Earth. This makes it a threat for geoeffective eruptions. NOAA forecasters estimate an 80% chance of M-class flares and a 50% chance of X-flares on Jan. 9th. Solar flare alerts: text, voice. Realtime Space Weather Photo Gallery SPACE WEATHER BALLOON LAUNCHED: Energetic protons are swirling around Earth this week. The ongoing radiation storm was triggered by an X-class solar flare on Jan. 7th, and two days later it is still going strong. To study the effects of the S3-category storm on Earth's atmosphere, yesterday the students of Earth to Sky Calculus launched a space weather balloon from the Sierra Nevada mountains of central California: Lofted by approximately 200 cubic feet of helium, the balloon ascended to an altitude of approximately 110,000 feet. Its payload contained an x-ray/gamma-ray dosimeter, a GPS altimeter, and a cryogenic thermometer. Together these instruments can form a complete thermal and radiation profile of the atmosphere throughout the flight. Of special interest are aviation altitudes--i.e., between 5 km and 15 km--where planes carry human passengers through the storm. The students want to find out how much ordinary air travelers are exposed during an event like this. The balloon popped as planned on Jan. 8th and the payload parachuted back to Earth, landing in a remote corner of Death Valley National Park. The students will recover the payload and its data on Jan. 9th. Stay tuned for results. Solar flare alerts: text, voice. Realtime Space Weather Photo Gallery VENUS, THE CRESCENT PLANET: Venus is turning its night side toward Earth as it approaches inferior solar conjunction on Jan. 11th. Less than 1% of Venus's sunlit hemisphere is now facing us, which means the planet looks like a razor-thin crescent. If you have a GOTO telescope, command it to slew to Venus. It's visible even in broad daylight: Shahrin Ahmad of Sri Damansara, Malaysia, took these pictures on Jan. 2nd, 6th and 8th using a 4.5 inch telescope. "It us very interesting to see how fast Venus changes in only 6 days! Today the thinning crescent is only 0.7% illuminated at a distance of 7o from the sun." Realtime Venus 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 Jan. 8, 2014, the network reported 20 fireballs. (19 sporadics, 1 Quadrantid)
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 Jan. 7, 2014, the network reported 30 fireballs. (29 sporadics, 1 Quadrantid)
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] 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 January 9, 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 | |