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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QUIET SUN: The sun is peppered with sunspots. However, they are all relatively small and none has the type of unstable magnetic field that is likely to explode. As a result, solar activity is very low and likely to remain so for days to come. NOAA forecasters say there is no more than a 5% chance of any strong solar flares this weekend. Aurora alerts: text or voice
COMET (and FRAGMENTS) APPROACH EARTH: On March 21st, green comet 252P/LINEAR will fly by Earth only 5.4 million km away-- the fifth closest cometary approach on record. One day later, a suspected fragment of the comet will pass even closer (3 million km). The name of the fragment is "P/2016 BA14," and Gregg Ruppel has photographed it zipping among the stars over Animas, New Mexico, on March 18th. Click to view a 40-minute time lapse video:
"I observed P/2016 BA14 using a 10-inch telescope and a STL11000 deep-sky CCD camera," says Ruppel.
By all accounts, the comet fragment is "pitifully faint." The parent comet, however, is relatively bright. Indeed, it is now on the threshold of naked eye visibility for observers in the southern hemisphere. Last night, Gerald Rhemann had little trouble photographing the 252P/LINEAR's green atmosphere from his backyard observatory in Namibia, Africa:
"I used a 12-inch telescope for this 360-second color exposure," says Rhemann.
The comet is green because its vaporizing nucleus emits diatomic carbon, C2, a gas which glows green in the near-vacuum of space. The verdant color will become even more intense in the nights ahead as 252P/LINEAR approaches Earth.
There is a chance that the comet's approach could cause a minor meteor shower. According to the International Meteor Organization, "[modeling by forecaster] Mikhail Maslov indicates that there might be a weak episode of faint, very slow meteors (15.5 km/s) on March 28–30 from a radiant near the star μ Leporis." Little is known about meteors from this comet, so estimates of the meteor rate are very uncertain. Maslov's models suggest no more than 5 to 10 per hour.
Realtime Comet Photo Gallery
[Resources: brightness measurements, 3D orbit, orbital elements]
RED SPRITES AT THE EDGE OF SPACE: Solar activity is very low. Nevertheless, space weather continues. High above late-summer thunderstorms in Africa, red sprites are dancing across the cloudtops, reaching up to the edge of space itself. Astronauts onboard the International Space Station photographed this specimen (circled) on March 14th:
Sprites are an exotic form of "upward lightning." They are a true space weather phenomenon, inhabiting the upper reaches of Earth's atmosphere alongside meteors, and some auroras. Some researchers believe sprites are linked to cosmic rays: subatomic particles from deep space striking the top of Earth's atmosphere produce secondary electrons that, in turn, could provide the spark that triggers the elaborate red forms.
Although sprites have been seen for at least a century, most scientists did not believe they existed until after 1989 when sprites were photographed by cameras onboard the space shuttle. They have since been photographed many times from the ISS.
You don't have to be in space, however, to see these things. "Sprite chasers" regularly photograph the upward bolts from their own homes. Give it a try!
Realtime Sprite Photo Gallery
Realtime Aurora Photo Gallery
Solar Eclipse Photo Gallery
Realtime Spaceweather 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 Mar. 19, 2016, the network reported 7 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 March 19, 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 |