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. | | |
QUIET WEEKEND: Solar activity remains low. With no sunspots actively flaring, the sun's X-ray output has flatlined. NOAA forecasters estimate a scant 1% chance of X-flares and a 10% chance of M-flares on Feb. 15th. Solar flare alerts: text, voice
VALENTINE'S SURPRISE: For Valentine's Day, night-sky photographer Alan Dyer received not red roses, but red auroras. "It was an odd display. Instead of the usual green, the lights over Manitoba, Canada, on Feb. 14th were a beautiful shade of red," says Dyer, who took this 25 second exposure using a Canon 6D digital camera and a fish-eye lens:
"The bright light at the right is Jupiter," he points out. "Later, the aurora took on the more normal appearance with green curtains topped by fringes of red."
Red auroras are not fully understood. They occur some 300 to 500 km above Earth's surface, much higher than ordinary green auroras. Some researchers believe the red lights are linked to low energy electrons from the sun, which move too slowly to penetrate deeply into the atmosphere. When such electrons recombine with oxygen ions in the upper atmosphere, red photons are emitted. At present, space weather forecasters cannot predict when this will occur.
Later today, a solar wind stream is expected to hit Earth's magnetic field, prompting NOAA forecasters to estimate a 40% chance of polar geomagnetic storms on Feb. 15th. Auroras are likely, although no one can say if any of them will be red. Stay tuned to the realtime aurora gallery for sightings. Aurora alerts: text, voice
Realtime Aurora Photo Gallery
MAGNETIC STORM ON COMET LOVEJOY: Around the world, observers of bright Comet Lovejoy (C/2014 Q2) are reporting activity in the comet's sinuous blue ion tail. On Feb. 13th, Michael Jäger of Dorfstetten Austriao used a backyard telescope to capture this 'plasma blob' billowing down the tail, away from the comet's core:
This could be a sign that a magnetic storm in underway. Observers of comets frequently witness plasma blobs and 'disconnection events' in response to CMEs and gusts of solar wind. In extreme cases, a comet's tail can be completely torn off.
The underlying physics is akin to terrestrial geomagnetic storms. When magnetic fields around a comet bump into oppositely-directed magnetic fields in a CME, those fields can link together or "reconnect." The resulting burst of magnetic energy can make waves, blobs, or even ruptures in the comet's tail. When CMEs hit Earth, a similar process takes place in the planet's magnetosphere powering, among other things, the aurora borealis.
Readers who wish to monitor the effects of space weather on Lovejoy should look toward the constellation Andromeda high in the northern sky after sunset: finder chart. The comet is shining like a 5th magnitude star, barely visible to the unaided eye from dark-sky locations, but an easy target for telescopes and binoculars. For pinpoint guidance of optics, use this ephemeris from the Minor Planet Center.
Realtime Comet Photo Gallery
Realtime Space Weather 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. 15, 2015, the network reported 19 fireballs.
(19 sporadics)
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 15, 2015 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. | | 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 |
