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SHADOW CAST ACROSS COMET LANDER: Mission controllers for ESA's Rosetta spacecraft have figured out where Philae landed on the surface of Comet 67P, and it's not good news. The lander appears to have bounced down in the shadow of a tall cliff. With little sunlight to draw upon, the lander's solar-powered batteries could run out of juice as early as this weekend, cutting short an unprecedented mission of discovery. European engineers are working rapidly to come up with a solution. Wish them luck and stay tuned.
OLD SUNSPOT RETURNS: Sunspot AR2192, the reports of your death were exaggerated. Yesterday, when the old sunspot first began to show itself following a two-week trip around the farside of the sun, it appeared to be in an advanced state of decay. Today, however, we can see that it is still a medium-to-large sunspot. Keep an eye on the circled area in this 48-hour movie from the Solar and Heliospheric Observatory:
This is the sunspot that made headlines last month as "the biggest sunspot in 25 years." During the second half of October, AR2192 crossed the face of the sun, blasting Earth's upper atmosphere with dozens of solar flares. Strong HF radio blackouts were a daily occurance, and millions of people glimpsed the great sunspot during a partial solar eclipse. If this old spot is returning with even a fraction of its former vigour, it could bring a sharp uptick in solar activity. NOAA forecasters estimate a 60% of M-flares and a 20% chance of X-flares on Nov. 14th. Solar flare alerts: text, voice
Realtime Space Weather Photo Gallery
RADS ON A PLANE: On Nov. 11th, Tony Phillips of spaceweather.com flew from California across the USA to attend a science communications meeting in Washington DC. As an experiment, he decided to take a radiation sensor onboard the plane. The results were eye-opening. During the apex of his flight to DC, cruising 39,000 feet above the desert between Reno and Phoenix, he recorded a dose rate almost 30 times higher than on the ground below:
There was no solar storm in progress. The extra radiation was just a regular drizzle of cosmic rays reaching down to aviation altitudes. This radiation is ever-present and comes from supernovas, black holes, and other sources across the galaxy.
In a single hour flying between Reno and Phoenix, the passengers on Phillips's flight were exposed to a whole day's worth of ground-level radiation--or about what a person would absorb from an X-ray at the dentist's office. That's not a big deal for an occasional flyer, but as NASA points out, frequent fliers of 100,000 miles or more can accumulate doses equal to 20 chest X-rays or about 100 dental X-rays. Lead aprons, anyone?
The radiation sensor is the same one that Earth to Sky Calculus routinely flies to the stratosphere to measure cosmic rays. It detects 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. Indeed, when the sensor passed through TSA security at the Reno airport, it began to buzz loudly, signaling a heavy dose of X-rays in the carry-on baggage scanner. TSA agents gathered around the instrument to investigate and they were quite interested when Phillips explained its function. Several wanted to know if they themselves were exposed to radiation in the vicinity of the luggage scanner; a quick survey of the area revealed no leaks.
After boarding the plane, Phillips monitored radiation levels closely. Dose rates tripled within 10 minutes of take-off and remained high for the duration of the flight. This simple experiment shows that space weather can touch us even when the sun is quiet. Imagine what an actual solar storm could do.
Realtime Aurora Photo Gallery
Realtime Comet Photo Gallery
Realtime Eclipse 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 Nov. 14, 2014, the network reported 17 fireballs.
(12 sporadics, 4 Leonids, 1 Northern Taurid)
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 November 14, 2014 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters: 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.
|Asteroid || |
|2014 UD192 || |
|2004 JN13 || |
|1998 SS49 || |
|2005 UH3 || |
|2007 EJ || |
|1991 VE || |
| ||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 |