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. SOLAR
WIND DRIES VENUS: The European Space Agency's
Venus Express spacecraft has made an important discovery: the solar
wind dries out Venus. Unlike Earth, Venus has no global magnetic
field to deflect particles from the sun; when solar wind hits Venus
it actually erodes the upper atmosphere. Hydrogen
and oxygen atoms fly into space, removing from Venus the chemical
building blocks of water. The process makes an already hellish
planet even worse. Get the full
story from the ESA.
COMET 17P/HOLMES:
Comet 17P/Holmes has been expanding relentlessly
since it exploded in late October and it now spans an angle nearly
1o wide in the night sky. "The comet is so large
that we hardly fit it in a single CCD frame," says Apostolos
Christou and David Asher of the Armagh Observatory who made this
2-frame movie of the comet moving among the stars on Nov. 22nd:
Each frame is a 30-second exposure through a Celestron
6-inch telescope. The time elapsed between frames is 45 minutes.
As Comet Holmes has expanded, so has it dimmed. Yet
it is still possible to spot the comet with the naked eye from dark
places in rural areas: sky
map. From light-polluted cities, binoculars are recommended
or, if you have them, try night
vision goggles.
"Comet Holmes is really spectacular when viewed
through night vision goggles," reports Mike Collins of the
New York State Police Aviation Unit. "Our medevac operation
uses them for added safety when landing at pickup scenes. Part of
the nightly ritual is alignment and focusing them after attaching
to our flight helmets. Even at light polluted Albany Airport the
comet pops right out."
Comet
17P/Holmes Photo Gallery
[Interactive
World Map of Comet Photos]
[sky
map] [ephemeris]
[3D orbit]
[Night
Sky Cameras]
LOWITZ ARCS! On
Nov. 23rd, Lori C. of King City, Canada, went outside at sunrise--"the
temperature was minus 9 degrees with snowy crystals in the air,"
she says--and photographed what at first appeared to be a garden-variety
ice halo: photo. Closer
inspection, however, reveals something rare and extraordinary: "Lori
captured the fabled Lowitz
arc," says atmospheric optics expert Les Cowley.
"The 'garden variety' arcs in Lori's photo are a sun
pillar flanked by two sundogs.
Look carefully at the sundogs and you will see the extremely rare
Lowitz arcs curving upwards and outwards away from the sun,"
he points out.
"Tobias Lowitz first
sketched them in St Petersburg over 200 years ago and controversy
has raged over their very existence ever since. They were first
photographed in the 1990s but they are still a hot topic of
debate. Lori’s arcs are ungerade-Lowitz arcs, ungerade because sunlight
had an odd number of reflections inside the Lowitz ice
crystals. Next time you see bright sundogs look carefully, Lowitz
arcs could be lurking there too!"
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