They came from outer space--and you can have one! Genuine meteorites are now on sale in the Space Weather Store. |
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QUIET SUN:
Solar activity is low. NOAA forecasters estimate
a 5% chance of M-class
solar flares and a scant 1% chance of X-flares
during the next 24 hours.
Solar flare alerts: text,
voice.
MOON HALO ALERT:
The Moon is waxing full, and that
means now is the time to be alert for Moon
halos. Photographer Steve Nilsen points out
this specimen over the shore of Kvæfjord in Troms,
northern Norway:
Moon halos are caused by ice
crystals in high, thin clouds. The angled faces
of the six-sided crystals bend moonlight into circles
22o in radius. (Sunlight can be bent
in the
same way.) Generally, the brighter the Moon,
the better the halo, which is why tonight is a good
time to look. The Moon will be full on Feb. 25th
at 20:26 UTC.
Note: According to folklore, tonight's
full Moon is the "Snow Moon," so-called
to mark the heavy snows of February.
Realtime
Space Weather Photo Gallery
CORONAL HOLE:
A dark gap in the sun's atmosphere--a "coronal
hole"--has opened up, and it is spewing a stream
of solar wind into space. NASA's Solar Dynamics
Observatory (SDO) photographed the opening during
the early hours of Feb 24th:
Wondering about the colors in this
image? This is how the sun looks through SDO's extreme
UV filters.
Coronal holes are places where the
sun's magnetic field opens up and allows the solar
wind to escape. A stream of solar wind flowing from
this particular coronal hole is expected to reach
Earth on or about March 2nd. High-latitude sky watchers
should be alert for auroras on that date. Aurora
alerts: text,
voice.
Bonus: The image also shows the magnetic
canopy of a sunspot group approaching just beyond
the sun's northeastern limb. The active region should
emerge in the next 24 hours.
Realtime
Aurora Photo Gallery
TWO COMETS AND THE
SOUTHERN LIGHTS: Two comets are
now visible in the skies of the southern hemisphere:
"Comet Lemmon and Comet PanSTARRS got close
enough together on the morning of Feb. 17th to fit
into single image with a 35mm lens," reports
Alex Cherney of Flinders, Victoria, Australia. "A
brief but reasonably strong aurora was a welcome
bonus." Click to set the scene in motion:
"Both comets were faint but visible
to the naked eye, C/2011 L4 (PanSTARRS) slightly
brighter than C/2012 F6 (Lemmon)," says Cherney.
"I would guestimate the visual magnitude of
Comet Lemmon at +5.5 and PanSTARRS at +5."
Also visible in Cherney's images are the Small Magellanic
Cloud and the 47 Tuc globular star cluster.
Comet Pan-STARRS is heading for a
close encounter with the sun just inside the orbit
of Mercury that could significantly boost its visibility
in early March. At that time, the comet will be
visible to northern-hemisphere observers as well.
A video
from NASA explores the possibilities.
More about Comet
Lemmon: 3D
orbit, ephemeris,
light
curves; and Comet Pan-STARRS: 3D
orbit, ephemeris,
light
curves.
Realtime
Comet Photo Gallery
Realtime
Noctilucent Cloud Photo Gallery
[previous years: 2003,
2004,
2005,
2006,
2007,
2008,
2009,
2011]
