Marianne's Heaven On Earth Aurora Chaser Tours Chasethelighttours.co.uk invites you to join them in their quest to find and photograph the Aurora Borealis. Experience the winter wonderland in the Tromsø Area.
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VERY QUIET SUN: Today, NOAA forecasters say there is a scant 5% chance of M-class solar flares. That might be an overestimate. There are only two small spots on the sun, and neither has the type of unstable magnetic field harbors energy for strong explosions. The sun is likely to remain quiet on Feb. 24th. Solar flare alerts: text or voice
AURORA SURPRISE: There was no geomagnetic storm last night, but sometimes geomagnetic storms are not required for bright auroras. "On Feb. 23rd we witnessed a mind-glowingly beautiful display," reports aurora tour guide Sarah Skinner of Abisko, Sweden. "At first the auroras were faint. Gradually they increased in intensity until--BOOM!--the sky was filled was rapidly dancing lights."
"The shapes and colours were amazing," continues Skinner. "Guests literally screamed with excitement, as did I!"
The cause of the outburst was not a CME or other solar storm. Instead, the interplanetary magnetic field (IMF) near Earth tilted south. This gentle event opened a crack in Earth's magnetosphere. Solar wind poured in to fuel the display.
More auroras are in the offing. A solar wind stream is expected to hit Earth's magnetic field on Feb. 24th or 25th. The impact could spark a G1-class geomagnetic storm around the Arctic Circle and--BOOM!--another display. Stay tuned. Aurora alerts: text or voice
Realtime Aurora Photo Gallery
CATS IN SPACE: On Feb. 16th, Spaceweather.com and the students of Earth to Sky Calculus launched a space weather balloon to monitor cosmic rays in Earth's atmosphere. A pair of cats went along for the ride:
"They belong to me," says reader Matt Comerford, who sponsored the flight. "It was great to see them 107,000 feet above Earth!"
The payload landed in a remote canyon on the east side of California's rugged White Mountains. A recovery team had to hike 19 miles to find the radiation sensors. Students are reducing the data now, and it looks like cosmic rays are still intensifying. Stay tuned for updates from the flight.
Realtime Spaceweather Photo Gallery
SNOW MOON HALO: According to folklore, Monday night's full Moon was the "Snow Moon," named after the heavy snows of February. "There was no snow falling in Stockholm," reports photographer Peter Rosén, "but a magnificent halo formed in the drifting clouds." Click on the Moon to set the scene in motion:
Maybe there was no snow, but the spectacle Rosén photographed was caused by a close relative of snowflakes--that is, ice crystals floating in high freezing clouds. Pencil-shaped ice crystals catch the moonlight and bend it into a 22o ring, as shown above. When you see such a halo, be alert for moondogs and moon pillars, too. They are formed by plate-shaped ice crystals that often accompany their pencil-shaped cousins.
Many ice halos surrounded last night's Snow Moon. Browse the photo gallery for more sightings:
Realtime Spaceweather Photo Gallery
Realtime Comet Photo Gallery
Every night, a network of NASA 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 Feb. 24, 2016, the network reported 23 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 ones
all the time.
On February 24, 2016 there were 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.
| ||Cosmic Rays in the Atmosphere |
These measurements are based on regular space weather balloon flights: learn more.
|Situation Report -- Oct. 30, 2015 ||Stratospheric Radiation (+37o N) |
|Cosmic ray levels are elevated (+6.1% above the Space Age median). The trend is flat. Cosmic ray levels have increased +0% in the past month. |
|Sept. 06: 4.14 uSv/hr (414 uRad/hr) |
|Sept. 12: 4.09 uSv/hr (409 uRad/hr) |
|Sept. 23: 4.12 uSv/hr (412 uRad/hr) |
|Sept. 25: 4.16 uSv/hr (416 uRad/hr) |
|Sept. 27: 4.13 uSv/hr (413 uRad/hr) |
|Oct. 11: 4.02 uSv/hr (402 uRad/hr) |
|Oct. 22: 4.11 uSv/hr (411 uRad/hr) |
Approximately once a week, Spaceweather.com and the students of Earth to Sky Calculus fly "space weather balloons" to the stratosphere over California. These balloons are equipped with radiation sensors that detect cosmic rays, a surprisingly "down to Earth" form of space weather. Cosmic rays can seed clouds, trigger lightning, and penetrate commercial airplanes. Our measurements show that someone flying back and forth across the continental USA, just once, can absorb as much ionizing radiation as 2 to 5 dental X-rays. For example, here is the data from a flight on Oct. 22, 2015:
Radiation levels peak at the entrance to the stratosphere in a broad region called the "Pfotzer Maximum." This peak is named after physicist George Pfotzer who discovered it using balloons and Geiger tubes in the 1930s. Radiation levels there are more than 80x sea level.
Note that the bottom of the Pfotzer Maximim is near 55,000 ft. This means that some high-flying aircraft are not far from the zone of maximum radiation. Indeed, according to the Oct 22th measurements, a plane flying at 45,000 feet is exposed to 2.79 uSv/hr. At that rate, a passenger would absorb about one dental X-ray's worth of radiation in about 5 hours.
The radiation sensors onboard our helium balloons detect X-rays and gamma-rays in the energy range 10 keV to 20 MeV. These energies span the range of medical X-ray machines and airport security scanners.
| ||The official U.S. government space weather bureau |
| ||The first place to look for information about sundogs, pillars, rainbows and related phenomena. |
| ||Researchers call it a "Hubble for the sun." SDO is the most advanced solar observatory ever. |
| ||3D views of the sun from NASA's Solar and Terrestrial Relations Observatory |
| ||Realtime and archival images of the Sun from SOHO. |
| ||from the NOAA Space Environment Center |
| ||the underlying science of space weather |