Come to Tromsø and share Marianne's passion for rural photography: Chasethelighttours.co.uk invites you to experience "Heaven on Earth" with an aurora, fjord, fishing, whale watching, photography or sightseeing tour.
MICROBES FROM ANTARCTICA SET TO LAUNCH: Only a few hours from now, Spaceweather.com and the students of Earth to Sky Calculus will launch approximately 100 billion microbes from Antarctica to the stratosphere, more than 110,000 ft above Earth's surface. The goal of the high-altitude balloon experiment is to discover if terrestrial extremophiles can survive extreme cold and high radiation at the edge of space. Stay tuned for updates.
MAGNETIC FILAMENTS ON THE SUN: With no sunspots actively flaring this weekend, solar activity is low. Or is it? There's more to solar activity than sunspots and flares. "I can't recall ever seeing as many magnetic filaments on the sun as I have this month," points out amateur astronomer John W. O'Neal of Amherst, Ohio. "This composite image is my tribute to the filament-ridden sun of May 2015."
Indeed, the sun has been unusually filamentary. Vast strands of plasma held together by magnetic fields have crept across the face of the sun all month long. Occasionally, these dark filaments become unstable and erupt, hurling parts of themselves into space. Fragments falling back to the stellar surface can explode, producing a type of flare called a Hyder flare--no sunspot required.
There is an extra-large filament on the solar disk today. It stretches more than 700,000 km from end to end--about twice the distance from Earth to the moon. These dimensions make it an easy target for backyard solar telescopes. If you have one, take a look. Solar flare alerts: text, voice
Space Weather Photo Gallery
NOCTILUCENT CLOUDS INTENSIFY: The northern summer season for noctilucent clouds (NLCs) is underway. Earth-orbiting satellites such as AIM and the International Space Station have been photographing the electric-blue clouds for days. On May 28th, sky watchers on Earth saw them, too. Andy Stables sends this picture from Isle of Skye, Scotland.
The fine-structured blue clouds floating above the dark, ordinary storm clouds are the NLCs. "The NLCs were coming through the twilight at 00:25 UT with some really nice ripple structures,"says Stables. They stretched about 15 degrees above the horizon."
NLCs are Earth's highest clouds. Seeded by meteoroids, they float at the edge of space more than 80 km above the planet's surface. The clouds are very cold and filled with tiny ice crystals. When sunbeams hit those crystals, they glow electric-blue.
Noctilucent clouds first appeared in the 19th century after the eruption of super-volcano Krakatoa. At the time, people thought NLCs were caused by the eruption, but long after Krakatoa's ash settled, the clouds remained. In recent years, NLCs have intensified and spread with sightings as far south as Utah and Colorado. This could be a sign of increasing greenhouse gases in Earth's atmosphere.
Observing tips: Look west 30 to 60 minutes after sunset when the Sun has dipped 6o to 16o below the horizon. If you see luminous blue-white tendrils spreading across the sky, you may have spotted a noctilucent cloud.
NLC Photo Gallery
RADAR ECHOES FROM THE NOCTILUCENT ZONE: Every summer since the late 1970s, radars probing Earth's upper atmosphere have detected strong echoes from altitudes between 80 km and 90 km. These altitudes comprise the "noctilucent zone," where water vapor crystallizes around meteor smoke to form icy noctilucent clouds (NLCs). The first NLCs of the 2015 northern summer season were spotted by NASA's AIM spacecraft on May 19th. The radar echoes have followed close behind.
Les Dean of the MST Radar Facility in Aberystwyth, Wales, reports: "We detected our first echoes of the summer season on May 26th."
Researchers call them "Polar Mesospheric Summer Echoes" or "PMSEs." They occur over the Arctic during the months of May through August, and over the Antarctic during the months of November through February. These are the same months that NLCs appear.
But do the radar echoes actually come from noctilucent clouds? "The association is controversial," notes Dean. A leading theory holds that the ice particles in noctilucent clouds are electrically charged, and this makes them good reflectors of HF radio waves. However, NLCs are not always visible when the radar echoes are observed and vice versa. So the connection is not clear-cut.
One thing is sure: the northern season for both NLCs and PMSEs has begun. Stay tuned for more echoes from the noctilucent zone.
UPDATE: "What is happening 90 km above Earth's surface?" wonders researcher Rob Stammes at the Polarlightcenter in Lofoten, Norway. For the past two nights, he has detected intense radio reflections using a forward scatter meteor radar. The phenomenon is almost surely linked to the PMSEs and noctilucent clouds reported above.
Sprite Photo Gallery
Aurora Photo Gallery
Comet Photo Gallery
Every night, a network
all-sky cameras scans the skies above the United
States for meteoritic fireballs. Automated software
maintained by NASA's Meteoroid Environment Office
calculates their orbits, velocity, penetration depth
in Earth's atmosphere and many other characteristics.
Daily results are presented here on Spaceweather.com.
On May. 29, 2015, the network reported 3 fireballs.
In this diagram of the inner solar system, all of the fireball orbits intersect at a single point--Earth. The orbits are color-coded by velocity, from slow (red) to fast (blue). [Larger image] [movies]
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.
May 30, 2015 there were 1584
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