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. | | | SUBSIDING PROTONS, MORE TO COME? Energetic protons are swarming past Earth in the aftermath of a magnetic explosion on the sun's western limb on Dec. 28th: movie. At its peak, the radiation storm registered "S1" on NOAA storm scales, which is to say it was a minor event with minimal effects on Earth-orbiting satellites and aviation. The storm is subsiding now. Stronger radiation storms are possible in the days ahead, however, as potent sunspot AR1934 rotates toward the western limb--a place with a strong magnetic connection to Earth. Flares from AR1934 could send more protons in our direction. Solar flare alerts: text, voice. MUST-SEE SUNSET PHENOMENON: Now is a great time to look at the second planet from the sun. Like the Moon, Venus has phases, and at the moment it is a 5% crescent. Moreover, it is bright enough to see in broad daylight. On Saturday, Mark Wloch pointed his Celestron C8 telescope at the blue sky over Southgate, Michigan, and this is what he saw: "I captured Venus during daylight with a jet passing by," says Wloch. "What a beautiful conjunction." Yes, it is easy to see Venus in broad daylight, but it is even easier to see the planet at sunset when Venus pierces the darkening sky like a beacon 150 times brighter than a 1st-magnitude star. Indeed, some sky watchers think Venus is an airplane. A quick look through a pair of binoculars, however, reveals the crescent. Point your optics southwest after sunset. No sky map is required; you can't miss Venus. Realtime Venus Photo Gallery COMING SOON--THE FIRST AURORAS OF 2014: Magnetic fields in the sun's northern hemisphere have opened up, creating a vast hole in the sun's atmosphere--a coronal hole. NASA's Solar Dynamics Observatory is monitoring the UV-dark gap: Coronal holes are places where magnetic fields threading through the sun's atmosphere spread apart and allow solar wind to escape. A stream of solar wind flowing from this particular coronal hole could reach Earth on Jan. 2-3, possibly sparking polar geomagnetic storms. The first auroras of 2014 are in the offing. Solar flare alerts: text, voice. 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 Dec. 27, 2013, the network reported 16 fireballs. (13 sporadics, 2 December Leonis Minorids, 1 December Hydrid)
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 Dec. 26, 2013, the network reported 24 fireballs. (21 sporadics, 3 December Leonis Minorids) 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 December 30, 2013 there were 1448 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 | |