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PROMINENCE ALERT:
For the second day in a row, astronomers
are monitoring a
lively
prominence
on the sun's northwestern limb. It is at least five times taller
than Earth and an easy target for backyard solar
telescopes.
VOLCANIC SUNSETS:
Volcanoes have been erupting in Alaska, and
now sunsets are turning campfire-red across the continental United
States. Coincidence? Kansas photographer Doug Zubenel calls this
snapshot The Colors of Kasatochi:
"I've been seeing these incredible sunsets since last Friday,"
says Zubenel. High resolution photos (#1,
#2) reveal the
source: a high-altitude layer of finely-structured aerosols. "A
rich orange develops as the sun sinks toward the horizon and Venus
sports a red annulus."
"Doug's skies were probably generated by the recent
eruptions of Kasatochi and two other volcanoes in Alaska's Aleutian
Islands," says atmospheric optics expert Les Cowley. "Volcanic
eruptions hurl gigantic clouds of fine dust and sulfur dioxide into
the stratosphere where high winds spread them around the globe.
Sulfur dioxide forms aerosols; these and the dust scatter sunlight
to give us red
skies, twilight
rays and Bishop's
rings. I'm getting many reports of unusual sunsets - look up!"
more images: from
Linda Neilsen of Kent, Washington; from
Dick McGowan of Olathe, Kansas; from
Jeff Stevens of Grass Lake, Michigan; from
Misty Lundberg of Princeton, Indiana; from
Edmund E Kasaitis of Manchester, Maryland; from
Doug
Zubenel
of De Soto, Kansas; from
Dan Bush of Albany, Missouri; from
Karla Dorman of Burleson, Texas;
LEAVING VICTORIA:
Opportunity is getting out while it still
can. The Mars rover has spent almost a whole year exploring the
perilous
slopes of Victoria Crater, an impact basin almost eight times
wider than a football field. With one of the rover's wheels now
in danger of failing, mission controllers have commanded Opportunity
back to the safety of the surrounding plains.
Spaceweather reader Stuart Atkinson of Kendal, England, offers
a farewell shot, 3D
glasses required:
Click
to view a full-sized 3D image
"This anaglyph is a combination of two pictures taken by the
rover's Rear Hazcam," Atkinson explains. "It shows Oppy
taking a last 'tourist photo' of the crater before heading back
up onto the plain of Meridiani in search of new sights."
According
to NASA, the "new sights" are cobbles--fist-size rocks
thrown long distances by deep impact events on Mars. Driving across
the plains in years past, Opportunity encountered scores of cobbles
but stopped to examine only a few. Mission scientists are thinking
that may have been a mistake. Cobbles don't sound glamorous, but
they could reveal much about layers of Mars even deeper than Victoria
Crater.
Farewell, Victoria! Hello cobbles. One wonders, what kind of 3D
images will they make?
Aug.
16th Lunar Eclipse Gallery
[Interactive
Eclipse Map]
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