| BEHOLD THE SUN:
Would you like to see fiery prominences and new-cycle sunspots
with your own eyes? On sale now: Personal
Solar Telescopes. |
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|
SPOOKY SKIES: It
must be Halloween. A solar wind stream is buffeting Earth's magnetic
field, stirring up ghostly
auroras around the Arctic Circle. Meanwhile, Venus and the Moon
are converging for a spooky conjunction at sunset. It's a boo-utiful
view! Get the full
story and a sky
map from Science@NASA.
BONUS: In an entertaining Youtube video, NASA
takes a look back to the Halloween Storms of 2003: watch
it!
NEW-CYCLE SUNSPOT:
A sunspot is emerging in the sun's northern
hemisphere and it appears to be a member of new Solar Cycle 24.
Sunspot 1007 is located at high latitude, as new-cycle sunspots
always are, and it has the magnetic
polariity expected of a Cycle 24 active region:
This is the fourth time in October that a new-cycle
sunspot has breached the sun's surface. (The previous three occasions
were Oct. 4th, 11th and 17th.) In a year of almost no
sunspots, four in a single month is a large number, and their
association with the new solar cycle is significant. It is a sign
that the sun is beginning a slow ascent out of solar minimum to
a more active phase in the months and years ahead. Solar minimum
is not a permanent condition!
Readers, if you have a solar
telescope, train it on sunspot 1007 to witness a sign of things
to come.
more images: from
J. Fairfull and J. Stetson of South Portland, Maine; from
Peter Paice of Belfast, Northern Ireland; from
Pavol Rapavy of Rimavska Sobota, Slovakia; from
Stephen Ames of Hodgenville, Kentucky;
COLORADO FIREBALL:
What are the odds? On Oct. 28th at 7:29 pm
Mountain Daylight Time, a random meteoroid hit Earth's atmosphere
and disintegrated with the luminosity of a full Moon. The impact,
which could've happened anywhere, took place directly above an all-sky
video camera in Guffey, Colorado:
Click
to view videos of the fireball
"I've received more than 100 eyewitness reports,"
says astronomer Chris Peterson,
who operates the camera as part of a nightly fireball monitoring
program. Combining the data at hand, he estimates that "the
meteor had a ground
path about 170 miles long and traveled from east to west at
34 km/s (76,000 mph)."
"I was lucky enough to see it myself from inside
my house through a window," adds Thomas Ashcraft. What's amazing
about that is he was located 300 miles away in New Mexico.
"It was brilliant turquoise and green and lasted more than
nine seconds." Ashcraft is an amateur radio astronomer and
his receivers picked up echoes of distant TV transmitters bouncing
off the fireball's ionized trail: listen.
Using a computer model of Earth's meteoroid environment,
Bill Cooke of the Marshall Space Flight Center calculates
that fireballs this bright come along once every five months or
so. Rarely, however, are they witnessed. About 70% of all fireballs
streak over uninhabited ocean while half appear during the day,
invisible in sunny skies. To catch one in the crosshairs of a meteor
camera on a dark albeit cloudy night is good luck indeed.
UPDATED: 2008
Orionid Meteor Gallery
[IMO meteor counts]
[2006 Orionids]
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