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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NEAR-EARTH ASTEROID, REVISED: Earlier this month, NASA reported that near-Earth asteroid 2013 TX68 might come very close to Earth on March 5th--only 11,000 miles away. New observations provide a different answer: The 30-meter wide space rock won't reach Earth until March 8th, and when it does, it will miss our planet by a wide margin of 3 million miles. The asteroid poses no threat to Earth. Get the full story from the Center for Near-Earth Object Studies at JPL.
SPHERICAL CAMERA AT THE EDGE OF SPACE: On Feb. 27th, Spaceweather.com and the students of Earth to Sky Calculus launched a helium balloon to the stratosphere to monitor increasing levels of cosmic rays. In addition to radiation sensors, the payload carried something special: a spherical camera. Click and drag on the image below to explore California's Sierra Nevada from an altitude of 115,300 feet--and don't forget to look up at the balloon!
Today, for the first time, we flew a spherical camera onboard one of our helium balloons. This is what the Sierra Nevada looks like from the edge of space. Click to view and navigate the interactive 3D image! #theta360 - Spherical Image - RICOH THETA
The camera, a Ricoh Theta S, will probably become a regular part of our cosmic ray payload. Imagery should improve in future flights as the students learn to lower the profile of the camera's thermal pack--the strange-looking black object in the center of the 3D image. During its flight to the stratosphere, the camera experienced temperatures as low as -65 C. The thermal pack helps keep the camera's batteries warm in these harsh conditions.
Next week, the camera will take another trip--to Indonesia. The students will be using it to record a total eclipse of the sun on March 9th. Stay tuned for that!
Realtime Spaceweather Photo Gallery
MAGNETIC CANYON ON THE SUN: Magnetic fields in the sun's atmosphere have split apart, forming a 'magnetic canyon' more than 500,000 miles long. NASA's Solar Dynamics Observatory is monitoring the structure, shown here in an extreme ultraviolet image taken on Feb. 28th:
The canyon is the dark linear feature vertically bisecting the solar disk. White arrows indicate solar wind spewing out into space. Such an opening is also called a "coronal hole." A stream of solar wind flowing from this coronal hole is expected to reach Earth on or about March 1st. NOAA forecasters say there is a 40% chance of polar geomagnetic storms when the stream arrives.
Realtime Aurora Photo Gallery
GEOSTATIONARY SATELLITES: Take a camera, point it at the night sky, and open the shutter for a few hours. The result will be star trails--beautiful arcs of light formed by the rotation of Earth, twirling the stars in concentric circles around the North celestial pole. Jamie Shepherd of Lochearnhead, Scotland, did this experiment on Feb. 27th, but found that not all the stars moved. Some were motionless. In fact, they were not stars, but rather geostationary satellites:
Geostationary satellites orbit Earth at an altitude of ~22,300 miles directly over the equator. They circle Earth once every 24 hours--the same amount of time it takes Earth to turn on its axis. This means geostationary satellites appear to be motionless in the sky above any given observer; hence, no star trails.
This is a great time of year to observe geostationary satellites. During the weeks around equinoxes, sunlight glints diectly from flat surfaces on the satellites' boxy bodies, making them extra bright.
So....Take a camera, point it at the night sky, and open the shutter for a few hours. The things that don't move might be as interesting as the things that do.
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. 28, 2016, the network reported 9 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 28, 2016 there were 1683 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 |