| Where's Saturn? Is that a UFO--or the ISS? What's the name of that star? Get the answers from mySKY--a fun new astronomy helper from Meade. || || |
AURORAS IN BROAD DAYLIGHT: Imagine living on a planet where Northern Lights fill the heavens at all hours of the day. Around the clock, even in broad daylight, luminous curtains shimmer and ripple across the sky. News flash--Astronomers have discovered such a planet. Its name is Earth: full story.
HEAVENLY MEETING: High overhead after sunset, a heavenly meeting is underway. Attendees are Comet 17/P Holmes and the California Nebula (NGC 1499):
"Wow, what a lovely pair," says photographer P-M Hedén of Vallentuna, Sweden. "This is a tuly unique event." To capture the giant comet (1o in diameter) and the even bigger nebula (more than 2o long) in a single frame, he used a wide-field WIlliam Optics WO66 APO telescope and a Canon Digtial Rebel XT. The convention is set to continue for many nights to come, making this a good week for astrophotography: sky map, ephemeris.
more images: from Michael Jäger of Stixendorf, Austria; from Mike Holloway of Van Buren, Arkansas;
SHADOW PLAY: Which is higher, the contrail or the sun halo? Examine this picture, then scroll down for the answer:
Photo details: Canon EOS 30D, EF-S 10-22mm
The contrail is higher. You can tell because it casts its shadow on the halo below.
"Here in Reykjavik, Iceland, sun halos have appeared frequently over the past few weeks," says photographer Fredrik Holm. With the contrail shadow adding depth, "this one was by far the most dramatic I observed."
Splitting halos: It is not strictly correct to say that "a shadow falls across the sun halo" because sun halos have no physical substance. (Just try to touch one!) The tangible thing that is shadowed is ice: Sun halos are formed by ice crystals floating in cirrus clouds. A gap in the halo is a sign that crystals are being deprived of sunlight from above.