Welcome to Sott.net
Tue, 25 Apr 2017
The World for People who Think

Fire in the Sky
Map

Meteor

The Curious Case of Comet Elenin: A Skywatching Tale

© Michael Mattiazzo
Amateur astronomer Michael Mattiazzo of Castlemaine, Australia caught these two images of comet Elenin on Aug. 19 (left) and Sept. 6, 2011. The images show a rapid dimming in the comet, possibly hinting at its disintegration.

Russian amateur astronomer Leonid Elenin had the good fortune to discover a comet on Dec. 10, 2010, and it's turned out to be quite a skywatching curiosity.

Initially, comet Elenin received quite a bit of attention from astronomers because its orbit would take it quite close to Earth, within 22 million miles (35 million kilometers), on Oct. 16, 2011. It looked like it was going to put on a good show.

Even as recently as Aug. 19, the comet was brighter than predicted, as observed and photographed by amateur astronomers in Australia, notably Michael Mattiazzo.

Then, disaster struck in the form of a coronal mass ejection from the sun. The next day the comet had dropped half a magnitude in brightness, and has continued to drop, despite the icy body getting closer to the sun. Apparently the comet is disintegrating, as sometimes happens when comets pass too close to the sun.

Meanwhile, this rather small and ordinary comet has become the subject of media frenzy among conspiracy theorists and 2012 doomsayers. Comet Elenin has been accused of being a brown dwarf or the mysterious and destructive planet "Nibiru," and has been blamed for earthquakes and tsunamis. Did you know that its discoverer's name is really an acronym for "Extinction Level Event: Nibiru Is Nigh."

On Sept. 10 the comet passed its perihelion, a phase marking its closest approach to the sun, at a distance of 44,840,000 miles (72,170,000 km).

Meteor

Meteor Caught on Video by Troy Stone



One of our valued readers here in Universe Today sent us a link to a video that was first featured in a local news channel in Florida. It was a video of a bright green fireball shooting across the sky in Orlando, Florida. The video was recorded by Troy Stone using a dash cam as he was on his way to work in the morning of September 5, 2011.

According to the locals who were able to post the sighting online, the meteor was heading east to west when looking south.

Sun

Solar Dynamics Observatory records an X1.4 Solar Flare and a Coronal Mass Ejection

This X1.4 class flare was recorded by the Solar Dynamics Observatory (SDO) on the morning of September 22, 2011, peaking at 7:01 AM ET. The movie is shown in multiple wavelengths of light simultaneously (211, 193, 171 angstrom). Across the top is a graph of the x-ray intensity during flare as recorded by the GOES spacecraft.


A large coronal mass ejection (CME) shot off the West (right) side of the sun at 6:24 PM ET on September 21, 2011. The CME is moving away from Earth at about 900 miles per second.

The next morning, an X1.4 class flare erupted from the other side of the sun, peaking at 7:01 AM ET on September 22. The flare came from sunspot N15E88, which is just moving into view as the sun rotates. This flare has caused elevated proton levels on the East (left) side of the sun. Associated with this flare, there was a significant CME, traveling at over 600 miles per second, that began around 7:24 AM ET.

Meteor

US: Fireball seen over Western Oregon

Image
© heagle 2052
A fireball streaked across the Oregon sky Wednesday evening.

Described as blue or green with a small tail, the object appeared shortly after 8 p.m. Reports of the sighting ran from Portland to Southern Oregon but seemed to be focused on the Central Willamette Valley and Central Oregon Coast.

Candace wrote on the KGW TV Facebook page that "my daughter and I saw it. We were driving from Canby to Aurora and were near the intersection of 99E and Barlow Rd. I hit the brakes because it looked like it was going to land in the road in front of the car, but disappeared off to the side of the road. It looked like one steak from a light green firework coming down from the sky."

Sun

Above the Aurora: An Amazing Space Fly-Over

Solar activity is picking up, and no one has a better view of its effect on Earth than the crew of the International Space Station. During a geomagnetic storm on Sept. 17th, astronauts recorded a must-see movie of auroras dancing underfoot:


Note how the underbelly of the space station glows green from the reflected light of the auroras below. Also, in the distance, Sirius the dog star and Orion the Hunter can be seen rising feet-first into the night sky.

The storm, which registered a moderate 6 on the 0-to-9 K-index scale of geomagnetic disturbances, was caused by a coronal mass ejection (CME) hitting Earth's magnetic field. It was just a glancing blow, but with CMEs that is often enough to spark bright auroras over both ends of Earth. The space station was flying over the southern hemisphere at the time of the display. Observers in the northern hemisphere saw it too.

Satellite

UARS Satellite Continued

NASA's UARS satellite is making its final orbits around Earth, tumbling and flashing brightly as it descends toward a Sept. 23rd re-entry. Amateur astronomer Jim Saueressig II caught the bus-sized satellite flying over Burlington, Kansas, on Sept. 20th (image). "It was easily visible in spite of the moonlight and the twilight of the sunrise. The tumble and associated flares were very apparent," he says.

Satellite tracking expert Ted Molczan has used USSTRATCOM's orbital elements of UARS to predict a decay time "late on Sep 23, roughly between 18:00 and 22:00 UTC." Click on the map to view ground tracks corresponding to this interval:

© NASA
"There is still potential for the estimated time of decay to shift somewhat before it begins to narrow down," cautions Molczan.

Meteor

Falling NASA Satellite Could Spark Stunning Light Show

A NASA satellite the size of a school bus is just days away from taking a fiery plunge into Earth's atmosphere and could set off a dazzling display when it does ... if anyone is able to see it.

NASA's 6 ½-ton Upper Atmosphere Research Satellite is due to fall somewhere on Earth Friday (Sept. 23), though exactly where and when remains a mystery.


If you happened to be lucky enough to be within viewing range of a satellite that is re-entering the atmosphere, the sight, put simply, would amount to a short-lived but spectacular fireworks display. Unlike a fireball meteor, whose flight across the sky might take no more than a few seconds, a re-entering satellite's path usually lasts much longer.

Satellite

Falling UARS satellite seen from space

Video of a pass of UARS satellite on Sept. 15, at an altitude of 250 kilometers, taken from the ground with a 14" telescope. More info here.


When NASA's Upper Atmosphere Research Satellite descends from orbit, will we see it coming? Veteran French astrophotographer Thierry Legault has already seen it, using a 14-inch telescope. The ghostly video clip above shows the UARS satellite tumbling at an altitude of 155 miles (250 kilometers) on Sept. 15.

Satellite

US: FEMA Prepared for Dead NASA Satellite's Plunge to Earth This Week?

With a massive dead NASA satellite due to plunge back to Earth this week, the Federal Emergency Management Agency (FEMA) is laying the groundwork for a fast response in case the 6 1/2-ton spacecraft falls over American soil. The defunct spacecraft, called the Upper Atmosphere Research Satellite (UARS), is projected to make and uncontrolled, fiery fall on Sept. 23, plus or minus a day, according to NASA.

Odds are that nobody will be beaned by any remaining chunks of the nearly $750 million spacecraft, with NASA experts forecasting a remote 1-in-3,200 chance of a possible injury from the satellite's debris. But re-entry specialists do expect about 26 different components from UARS to survive the plunge - a total leftover mass of 1,170 pounds (532 kilograms) - components made of titanium, aluminum, steel and beryllium.


It is impossible to pinpoint just where UARS satellite debris will fall. With Earth being three-fourths oceans, the odds of a harmless splashdown are good. But NASA estimates the debris footprint will be about 500 miles (804 kilometers) long. The word from NASA is direct: "If you find something you think may be a piece of UARS, do not touch it. Contact a local law enforcement official for assistance." [Photos: Space Debris & Cleanup Concepts]

That's where FEMA comes in.

Sun

The Secret Lives of Solar Flares

© R. Astronomical Society
Sunspots sketched by R. Carrington on Sept. 1, 1859.

One hundred and fifty two years ago, a man in England named Richard Carrington discovered solar flares.

It happened at 11:18 AM on the cloudless morning of Thursday, September 1st, 1859. Just as usual on every sunny day, the 33-year-old solar astronomer was busy in his private observatory, projecting an image of the sun onto a screen and sketching what he saw. On that particular morning, he traced the outlines of an enormous group of sunspots. Suddenly, before his eyes, two brilliant beads of white light appeared over the sunspots; they were so bright he could barely stand to look at the screen.

Carrington cried out, but by the time a witness arrived minutes later, the first solar flare anyone had ever seen was fading away.

It would not be the last. Since then, astronomers have recorded thousands of strong flares using instruments ranging from the simplest telescopes in backyard observatories to the most complex spectrometers on advanced spacecraft. Possibly no other phenomenon in astronomy has been studied as much.

After all that scrutiny, you might suppose that everything about solar flares would be known. Far from it. Researchers recently announced that solar flares have been keeping a secret.

"We've just learned that some flares are many times stronger than previously thought," says University of Colorado physicist Tom Woods who led the research team. "Solar flares were already the biggest explosions in the solar system - and this discovery makes them even bigger."