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.
| || |
MAGNIFICENT ERUPTION: Breaking the quiet in spectacular fashion, a magnetic filament erupted from the sun's northern hemisphere at approximately 2145 UT on Sept. 29th. NASA's Solar Dynamics Observatory recorded the blast:
Another movie from the Solar Dynamics Observatory zooms in to show the filament ripping through the sun's atmosphere and leaving behind a "canyon of fire." The glowing "canyon" traces the channel where magnetic forces held the filament aloft before the explosion.
This event also hurled a magnificent CME into space: movie (Credit: SOHO). The magnetized cloud, which left the sun traveling approximately 900 km/s (2 million mph), was not aimed toward Earth. Nevertheless, our planet's magnetosphere might receive a glancing blow on Oct. 2-3. Polar geomagnetic storms and auroras are possible when the CME arrives. Stay tuned for updates. Geomagnetic storm alerts: text, voice.
Realtime Space Weather Photo Gallery
COMET ISON APPROACHES MARS: In two months, Comet ISON will make a spectacular flyby of the sun. First, though, it has to fly by Mars. The sungrazing comet is approaching the Red Planet for a 0.07 AU close encounter on October 1st. Mars satellites and rovers will have a close-up view. A video from NASA details the encounter.
Amateur astronomers on Earth can watch, too. Using a remotely controlled 14-inch telescope in New Mexico, Rolando Ligustri photographed ISON approaching Mars on September 28th:
At closest approach on October 1st, Mars and Comet ISON will be approximately 2o apart. While Mars is visible to the unaided eye (it shines almost as brightly as a first-magnitude star), ISON is definitely not. The comet is still far from the sun and, as it crosses the orbit of Mars, it has not yet warmed enough to reach naked-eye visibility. Reports of the comet's brightness vary from 12th to 14th magnitude, which means a mid-sized backyard telescope is required to see it.
Mars and ISON rise together in the eastern sky a couple of hours before the sun. Amateur astronomers, if you have a GOTO telescope, enter these coordinates. Visually, Mars will be easy to find on the mornings of closest approach, not only because the planet is relatively bright, but also because the crescent Moon will be passing right by it. Sky maps: Sept. 28, 29, 30; Oct. 1, 2.
New images of the comet are coming in every day. Browse the gallery for the latest views:
Realtime Comet ISON Photo Gallery
OHIO FIREBALL: On Sept. 27th, a meteor exploded in the skies above the US midwest. Witnesses report shadows cast upon the ground, unusual sounds, and a swirling contrail marking the aftermath of the blast. "It was the most brilliant fireball that I have ever seen!" reports Angela McClain, who sends this picture from Faith Ranch in Jewett, Ohio:
"The entire landscape lit up," she continues. "I spun around and there it was, a huge, bright green light, streaking across the sky. Even when it was gone, there was still a bright line in the sky about 20 seconds later. We were all stunned."
A NASA all-sky camera in Hiram, Ohio, also recorded the fireball: movie.
"This was a very bright event," says Bill Cooke of NASA's Meteoroid Environment Office. "Flares saturated our meteor cameras, and made determination of the end point (the terminus of the fireball's flight through the atmosphere) virtually impossible. Judging from the brightness, we are dealing with a meter class object."
Data from multiple cameras shows that the meteoroid hit Earth's atmosphere traveling 51 km/s (114,000 mph) and passed almost directly over Columbus, Ohio. Cooke has prepared a preliminary map of the ground track. According to the American Meteor Society, the fireball was visible from at least 14 US states.
Realtime Aurora Photo Gallery
Realtime Noctilucent Cloud Photo Gallery
[previous years: 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2011]