These pictures are almost too hot to touch. Metallic photos of the sun make great Christmas gifts.
LUNAR ECLIPSE: The lunar
eclipse of Dec. 21st falls on the same date
as the northern winter solstice. Is this rare? It
is indeed, according to Geoff Chester of the US
Naval Observatory, who inspected a list of eclipses
going back 2000 years. "Since Year 1, I can
only find one previous instance of an eclipse matching
the same calendar date as the solstice, and that
is Dec. 21, 1638," says Chester. "Fortunately
we won't have to wait 372 years for the next one...that
will be on Dec. 21, 2094."
WHEN TO LOOK:
The total eclipse lasts more than an hour from 02:41
am to 03:53 am EST on Tuesday morning, Dec. 21st.
Any time within that interval is a good time to
look. For other time zones, consult Shadow &
IN THE STRATOSPHERE: Earth's stratosphere
is as clear as it's been in more than 50 years.
University of Colorado climate scientist Richard
Keen knows this because he's been watching lunar
eclipses. "Since 1996, lunar eclipses have
been bright, which means the stratosphere is relatively
clear of volcanic aerosols. This is the longest
period with a clear stratosphere since before 1960."
Consider the following comparison of a lunar eclipse
observed in 1992 after the Philippine volcano Pinatubo
spewed millions of tons of gas and ash into the
atmosphere vs. an "all-clear" eclipse
Keen explains why lunar eclipses can
be used to probe the stratosphere: "At the
distance of the Moon, most of the light refracted
into the umbra (Earth's shadow) passes through the
stratosphere, which lies 10 to 30 miles above the
ground. When the stratosphere is clear, the umbra
(and therefore, the eclipsed Moon) is relatively
bright. On the other hand, if the atmospheric lens
that illuminates the Moon becomes dirty enough,
light will be blocked and the eclipse will appear
This is timely and important because
the state of the
stratosphere affects climate; a clear stratosphere
"lets the sunshine in" to warm the Earth
below. At a 2008 SORCE conference Keen reported
that "The lunar eclipse record indicates a
clear stratosphere over the past decade, and that
this has contributed about 0.2 degrees to recent
What will the eclipse 21st eclipse
look like? "The stratosphere is still fairly
clear, and the December 2010 eclipse should be normally
bright," predicts Keen. "I welcome any
and all reports on the brightness of future lunar
eclipses for use in my volcano-climate studies.
While actual brightness
measurements (in magnitudes) made near mid-totality
are most useful, I can also make use of Danjon-scale
ratings of the eclipse. Please be sure to note the
time, method, and instruments used in your reports."
Submit your observations here.
more eclipse resources:
STORM: Saturn's great "Dragon
Storm" has returned. The ferocious thunderstorm
observed for years by NASA's Cassini spacecraft
has recently been hiding under high clouds, but
now it is showing itself again. Using an 11-inch
telescope, Christopher Go of the Philippines
photographed the white tempest on Dec. 13th:
"The storm was so bright, I was
even able to see it visually [through the eyepiece],"
says Go. In years past, the storm was located in
Saturn's southern hemisphere, "but images taken
by me and other amateur astronomers show that it
is now in the northern hemisphere." The shift
is consistent with findings that the Dragon Storm
is a long-lived disturbance deep within the gas
giant's atmosphere that moves around and periodically
flares-up to produce large, visible storm regions.
Stay tuned for updates and more images.
Geminid Meteor Photo Gallery
Defy Explanation"] [meteor
2010 Aurora Gallery
[previous Novembers: 2009,
Potentially Hazardous Asteroids (PHAs
are space rocks larger than approximately 100m that
can come closer to Earth than 0.05 AU. None of the
known PHAs is on a collision course with our planet,
although astronomers are finding new
all the time.
December 20, 2010 there were 1167
potentially hazardous asteroids.
Notes: LD means
"Lunar Distance." 1 LD = 384,401 km, the distance
between Earth and the Moon. 1 LD also equals 0.00256
AU. MAG is the visual magnitude of the asteroid on
the date of closest approach.
official U.S. government space weather bureau
first place to look for information about sundogs,
pillars, rainbows and related phenomena.
call it a "Hubble for the sun." SDO
is the most advanced solar observatory ever.
views of the sun from NASA's Solar and Terrestrial
and archival images of the Sun from SOHO.
the NOAA Space Environment Center
underlying science of space weather