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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JUPITER AND THE MOON: When the sun goes down tonight, step outside and look east. Jupiter and the Moon are in conjunction only 2 degrees apart. Try to catch them before the sky fades to black. The sight of Jupiter and the Moon so close together and framed by twilight blue is a heavenly way to end the day. [sky map]
A SOLAR WIND STREAM IS COMING: Geomagnetic activity should remain low throughout the weekend. Conditions could shift to an active state on Monday, April 18th, when Earth enters a stream of high-speed solar wind. The solar wind is flowing out of this coronal hole on the sun:
Coronal holes are places in the sun's upper atmosphere where magnetic fields peel back, allowing solar wind to escape. In the image, above, from NASA's Solar Dynamics Observatory, the flow of solar wind is traced by arrows. The escaping material is now crossing the sun-Earth divide with an ETA of 48 hours.
The incoming solar wind stream is filled with positive-polarity magnetic fields. This means it might not do a good job sparking auroras. Positive polarity magnetic fields from the sun do not easily link to Earth's planetary magnetic field. As a result, their effect on our magnetosphere is often muted. Stay tuned for updates.
Realtime Aurora Photo Gallery
SUNSPOT SUNSET: Sunspot AR2529 is so big, people are noticing it in the sunset. Rayann Elzein saw it Thursday evening in Nijmegen, The Netherlands:
"I went for a random walk in the nature to capture photos of the sunset," says Elzein. "There were some thin clouds filtering most of the sunlight, which allowed me to see this major sunspot with the naked eye. Here it is!"
Caution: Even when the sun is dimmed by low-hanging clouds or haze, it can still be dangerously bright, especially when magnified by unfiltered optics. If you chose to photograph the low sun, as Elzein did, use the camera's LCD screen for safe viewfinding. Never look into the eyepiece of an unfiltered camera or telescope when the sun is in the field of view.
Although it is large, AR2529 is mostly quiet. The behemoth sunspot has a stable magnetic field that poses little threat for strong explosions. NOAA forecasters say there is no more than a 15% chance of M-class solar flares this weekend. Solar flare alerts: text or voice
Realtime Space Weather Photo Gallery
SPACE ROSES: Last week, the students of Earth to Sky Calculus launched a daring experiment. Daring for the flowers, that is. A bouquet of live roses flew to the edge of space onboard a helium balloon to find out if if they could survive the trip. The answer, apparently, is "yes." Here are the blossoms floating 35.4 km (116,000 feet) above Earth's surface:
The roses were hitchikers on a cosmic ray payload, which went to the stratosphere to monitor increasing levels of space radiation. En route to the top, the flowers were exposed to a dose of cosmic rays 100x Earth normal, air pressures as low as 0.2% of sea level, and temperatures as low as -63 C. Three hours later, the roses parachuted back to Earth and landed ... in Death Valley! Talk about a rough trip.
And now we come to Mother's Day. These flowers, which were pressed after recovery, are available as gifts. Buy one here and give mom something truly out of this world on May 8th. Each pressed rose comes with a unique card showing the flowers in flight. All proceeds support the student space weather research of Earth to Sky Calculus.
Solar Eclipse Photo Gallery
Realtime Comet Photo Gallery
[More about Comet 252P: brightness measurements, 3D orbit, orbital elements]
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 Apr. 17, 2016, the network reported 14 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 April 17, 2016 there were 1694 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 |