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.
SUBSIDING STORMS: Earth is exiting a solar wind stream that caused spectacular auroras earlier this week. NOAA forecasters have lowered the odds of polar geomagnetic storms on Oct. 10-11 to 35%. Aurora alerts: text or voice
THE SUN IS FLATLINING: Solar activity is very low. There is only one small sunspot on the Earth-facing side of the sun, and it has a simple magnetic field that poses no threat for strong flares. As a result, the sun's X-ray output is flatlining.
Inset above are the latest X-ray data from NOAA's GOES satellites. Only a few B-flares interrupt the past three days of persistent low activity. The source of these negligible flares is sunspot AR2430, barely visible on the solar disk.
The quiet is likely to continue throughout the weekend. NOAA forecasters say the odds of a strong flare on Oct. 10th is no more than 1%. Solar flare alerts: text or voice
Space Weather Photo Gallery
UFO MYSTERY SOLVED: On Oct. 8th, sky watchers in Asia witnessed a mysterious apparition: a number of point-like objects flew through the night sky accompanied, in some cases, by a luminous nebula. "The 'UFO' had lots of parts," says Jeff Dai, who photographed it moving over the Ganden Monastery in Lhasa, Tibet:
"It was also seen in the Xinjiang and Tianjin provinces of China," he adds. "Was it a UFO or a rocket?"
According to satellite expert Ted Molczan, it was a rocket. Or rather, a spy satellte.
He explains: "The sightings are related to the Thursday's launch of NOSS 3-7, [a pair of surveillance satellites belonging to the National Reconnaissance Office]. The lower, solid streak in Dia's photo was left by the NOSS payloads. The upper, bright streak is the Centaur that deployed the NOSS into their 63.4 deg, 1100 x 1200 km orbit. The Centaur appears to have been in the midst of the first of two burns to manoeuvre its orbit."
About an hour and a half later, a similar photo was taken by Ehsan Rostamizadeh from Iran:
"The solid track is the Centaur," says Molczan. "The wide, nebulous streak is the plume from the Centaur's fuel dump, which probably was completed a short time before the photo was taken."
The spy satellites are now in orbit. They are latest additions to the Naval Ocean Surveillance System (NOSS). Circling Earth in pairs and triplets, NOSS satellites are used by the US Navy to pinpoint radar and other electronic transmissions from ships at sea.
BLUE SKIES ON PLUTO: Earth isn't the only planet with blue skies. Pluto has them, too. The first color images of Pluto's atmosphere were beamed back to Earth by NASA's New Horizons spacecraft just last week, and the sky looks a lot like home:
New Horizons took the picture just after it sped by Pluto on July 14, 2015. The spacecraft's cameras were looking back at Pluto's nightside as sunlight illuminated the fringe of blue around Pluto's circumference.
"Who would have expected a blue sky in the Kuiper Belt?" says Alan Stern, principal investigator of the New Horizons mission. "It's gorgeous."
Carly Howett of the New Horizons science team explains the phenomenon: "A blue sky often results from scattering of sunlight by very small particles. On Earth, those particles are nitrogen molecules. On Pluto they appear to be soot-like particles we call tholins."
The term "tholin" was coined by Carl Sagan and Bishun Khare to describe organic substances they obtained in Miller-Urey experiments on gas mixtures akin to atmosphere of Saturn's moon Titan. On Pluto, tholins form high in the atmosphere where UV sunlight breaks apart nitrogen and methane molecules. The fragments re-combine to form complex macromolecules. These macromolecules continue to combine and grow until they become "tholins."
Ironically, tholins themselves are not blue. They merely scatter blue light. When tholins fall to the ground they show their true colors: gray or red. At least some of Pluto's patchy red coloring is thought to result from a gentle rain of these particles from the planet's atmosphere.
Aurora Photo Gallery
Eclipse Photo Gallery
Sprite Photo Gallery
||Cosmic Rays in the Atmosphere
These measurements are based on space weather balloon flights, described below.
|Situation Report -- Oct. 8, 2015
||Stratospheric Radiation (+37o N)
|Cosmic ray levels are elevated (+6.2% above the Space Age median). The trend is flat. Cosmic ray levels have increased +0% in the past month.
|Sept. 06: 414 uRad/hr
|Sept. 23: 412 uRad/hr
Introduction: Once a week, and sometimes more often, Spaceweather.com and the students of Earth to Sky Calculus fly "space weather balloons" to the stratosphere. These balloons are equipped with radiation sensors that detect cosmic rays, a form of space weather important to people on Earth. Cosmic rays can alter the chemistry of the upper atmosphere, seed clouds, spark exotic forms of lightning, and penetrate commercial airplanes. This last point is of special interest to the traveling public. 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. From now on we will present the results of our regular weekly balloon flights in this section of our web site. Here is the radiation profile from our latest flight:
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 nearly 100x 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 Sept. 27th measurements, a plane flying at 45,000 feet is exposed to 288 uRads/hr. At that rate, a passenger would absorb about one dental X-ray's worth of radiation in 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.
Stay tuned for improvements to this section in the days and weeks ahead as we develop a glossary and better plain language strategies for communicating this information. Suggestions are welcomed.
Every night, a network
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 Oct. 10, 2015, the network reported 25 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
all the time.
October 10, 2015 there were 1617
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.
official U.S. government space weather bureau
first place to look for information about sundogs,
pillars, rainbows and related phenomena.
call it a "Hubble for the sun." SDO
is the most advanced solar observatory ever.
views of the sun from NASA's Solar and Terrestrial
and archival images of the Sun from SOHO.
the NOAA Space Environment Center
underlying science of space weather
||Web-based high school science course with free enrollment