Strange Skies
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Fireball

Fireball seen across Pacific Northwest

Screenshot of AMS map
© Screenshot of AMS mapMap of where the fireball was reported seen.
Portland, Oregon - Many people throughout the Pacific Northwest reported seeing a "fireball" blazing through the sky at around midnight Friday.

According to the American Meteor Society, more than 130 people reported seeing the light shoot across the sky. It was reported seen as far south as Grants Pass and as far north as Port Angeles, Washington. Most of the reports came from the Willamette Valley.

Videos and photos of the fireball were posted on social media.

Question

Stratospheric deviation in wind pattern reversal observed for the first time

Earth’s stratosphere
© NASA/JSC Gateway to Astronaut Photography of EarthEarth’s stratosphere lies just above the red-orange troposphere in this photo snapped by International Space Station astronauts in 2011. Late last year, unusual wind behavior interrupted a reliable stratospheric wind pattern known as the quasi-biennial oscillation.
For the first time, scientists have observed a deviation from the typical alternating pattern of easterly and westerly winds in the equatorial stratosphere.

The weather we experience on Earth typically occurs in the troposphere, the lowest layer of the atmosphere. But the stratosphere, which envelops the planet just above the troposphere, is home to winds of its own. In a new study, Newman et al. report an anomalous interruption in an otherwise reliable stratospheric wind pattern known as the quasi-biennial oscillation.

Each cycle of the quasi-biennial oscillation begins with strong westerly winds that flow through the stratosphere in a belt around the equator. Over the course of about 1 year, these winds gradually weaken and descend in altitude to the lower stratosphere as easterly winds replace them. These easterly winds slowly sink and weaken, too, as westerly winds return. The cycle repeats roughly once every 28 months.

Since 1953, scientists have observed equatorial winds by instruments known as radiosondes, which are carried skyward by weather balloons. The quasi-biennial oscillation was discovered in the early 1960s. Although the timing of each cycle has sometimes varied by a few months, the pattern as a whole has remained uninterrupted—until now.

Sun

Solar eclipse to be observable over much of Africa

Solar Eclipse Sept 2016
© Larry Koehn/ShadowandSubstance
Sky watchers in more than 50 African countries are about to witness a solar eclipse. On Thursday, Sept.1st, the Moon will pass in front of the sun, covering as much as 97% of the solar disk. Click here to view an animated eclipse map created by Larry Koehn of ShadowandSubstance.com.

This is not a total eclipse, but rather an annular one, in which maximum coverage leaves a thin strip of sun shining around the lunar limb. The narrow path of annularity snakes across Gabon, Republic of Congo, Democratic Republic of Congo, Tanzania, Mozambique, and Madagascar. For as much as three minutes, people in those countries can see the "ring of fire":

Cloud Grey

Multiple lenticular clouds form over Washington state

Lenticular clouds over Central Washington
© Wendy PeteMultiple lenticular clouds spotted over the Columbia River Gorge in Central Washington on Aug. 28, 2016.
Glancing at the skies over the Pacific Northwest Saturday might have had you wondering if a request to be taken to your leader was not too far behind.

But no, it wasn't an alien invasion, just an invasion of cooler air from the Pacific Ocean that put a surreal visual stamp on the end of the recent hot weather. The spooky looking clouds are "lenticular" clouds -- so named for their lens-like shape, and while they might look ominous, the clouds themselves are fairly benign.

Lenticular clouds are created when the atmosphere is moist and almost -- but not quite -- to the point of condensation. They are most commonly seen in the Pacific Northwest near the large mountaintops, especially over and around Mt. Rainier.

As air flows over the summit, the mountain creates just enough lift that the air cools the few degrees it needs to condense into a cloud. Then when the air sinks down the windward side of the mountain, it warms and dries out, and essentially goes back to being invisible.
Lenticular clouds over Washington state
Depending on the horizontal air flow, you can get secondary and tertiary lenticular clouds downstream as the air propagates in the Rainier-caused turbulence where the air rises enough again to condense into a cloud, then sinks down again. And depending on how the air stacks up vertically, you can get several layers of clouds stacked like thin pancakes that give way to unusual shapes.

Watch this time lapse video from Saturday showing how the clouds form and appear to float in place:


Comment: More pictures from a photographer at Mt. Rainer:




Galaxy

Spectacular drone footage captures early Northern Lights over Iceland

Northern lights over Iceland
© OZZO ICELAND / YouTube
It's the Northern Lights as you've never seen them before: Filmed from a drone traveling across Iceland's stark scenery and clear night skies, Aurora Borealis has the perfect environment in which to shine.

It seems that the Northern Lights season - which typically runs from September to mid-April - has reached Iceland a little early this year, treating islanders to a spectacular celestial display.

One minute and 46 seconds of pure serenity, the drone captures every magnificent streak of color as the phenomenon stretches across the night sky.

Cloud Grey

Stunning 'fire rainbow' seen over Lavonia, Georgia

Circumhorizontal arc in Georgia
© Stacey Wood
Take a look at the attached image! It's what appears to be a rare "fire rainbow" in Lavonia, Georgia, captured by Stacey Wood. This occurs when the ice crystals in the high level clouds refracts the sunlight in just the right way.

It is not caused by fire, so the name "fire rainbow" can be misleading. When it is fully formed, it will make a complete arc across the clouds.

We don't see these very often, so I am thrilled that Stacey got this snapshot!

Fireball

Asteroid zooms past Earth hours after discovery

Asteroid 2016 QA2 was twice as big as the space rock that entered over Russia in 2013, breaking windows in 6 Russian cities. It passed safely Saturday night

The calculated orbit of 2016 QA2.
© JPL Small Body Database/Sciencythoughts BlogspotThe calculated orbit of 2016 QA2.
An asteroid safely passed by our planet on Saturday night - August 27-28, 2016 - just hours after being detected. Astronomers have labeled the space rock as asteroid 2016 QA2. The rocks is estimated to be at least twice as big as the Chelyabinsk meteor that penetrated the atmosphere over Russia in February, 2013.

According to the Minor Planet Center, closest approach to Earth occurred August 28 at 01:24 UTC (9:24 p.m. EST on August 27; translate to your time zone). The asteroid has an estimated size of 111.5 feet (34 meters), although its exact dimension can range between 52-171 feet (16 to 52 meters).

The speeding space rock came considerably closer than the moon, as it passed at just 0.22 the Earth-moon distance. That's about 52,580 miles (84,619 km) away. For comparison, the moon is located at some 239,000 miles (384,633 km) from Earth.

Asteroid 2016 QA2 was first seen by the SONEAR Observatory at Oliveira, Brazil.

Cloud Grey

Creepy mushroom cloud over Russian town scares the hell out of residents

cumulo-nimbus
© Instagram: khsy_20_
A massive anvil cumulo-nimbus thunderstorm cloud over Siberia left residents wondering if somebody dropped a nuclear bomb. Residents of Kemerovo in Russia's Western Siberia began posting images on Sunday of what looked like the distinctive hallmark of a nuclear explosion - an isolated ominous mushroom cloud surrounded by otherwise undisturbed blue skies.

The shocking and rare sight of such a massive anvil cumulo-nimbus cloud, formed when a major thunderstorm becomes so powerful that it begins to reach the highest levels of the atmosphere causing the cloud tops to be blown to the side by wind shear, startled many local residents who feared a nuclear blast or an explosion at one of the coal mines in the Kuzbass region.

Other residents however joked about the fearsome sight of the mushroom cloud with one Instagram user, @Kemerovo_insta, joking that there was "a nuclear war today in Chusovitino."


Snowflake

Another 'rare' circumhorizontal arc seen in Tennessee skies

Circumhorizontal arc in TN
© Keith Brown
Did you happen to notice a strange, horizontal-looking rainbow cloud in the sky on Monday? Many people contacted the WATE 6 On Your Side Storm Team asking about it.

It looked like a rainbow, but we didn't have any rain Monday. These really aren't rainbows. They are called circumhorizontal arcs.

They form by light passing through wispy, high-altitude cirrus clouds. They are rather rare because they are only seen when the sun is very high in the sky, more than 58 degrees above the horizon. Another important factor is that the hexagonal-shaped ice crystals within the high, thin cirrus clouds need to be thick plates with their faces parallel to the ground. So, as you can imagine, this is often a difficult task to get these events to occur at the same time.

When the sun's light enters through a vertical side of this ice crystal and leaves from the bottom face, it refracts, or bends in the same way that light passes through a prism. If the cirrus's crystals are aligned just right, the whole cloud lights up in a spectrum of colors.
Circumhorizontal arc in TN
© Keith Brown

Comment: A few days before, another not-so-rare circumhorizontal arc was seen in North Carolina. It appears to be happening more often due in part to atmospheric conditions that include increased particulates in the atmosphere from a rise in volcanic ash, dust and 'meteor dust' left by fireballs exploding in our atmosphere.


Rainbow

'Rare' circumhorizontal arc spotted in Greensboro, North Carolina

Circumhorizontal arc in NC
© Zoran Wilkes
It might look like rainbow and you might have even heard it called a fire rainbow, but what some people saw in the sky last Friday was a circumhorizontal arc.

A rare sighting that can only be seen in the Triad from March through September a circumhorizontal arc is a phenomenon caused by the sunlight hitting ice crystals just right in the atmosphere. This occurs when sun- or moonlight is refracted in a plate-shaped ice crystal that is suspended in the atmosphere, typically in high cirrus clouds.

The process that causes the circumhorizontal arc is just like the effect of when you shine light into a prism.

In ideal conditions, the arc appears as a large, brightly spectrum-colored band that appears parallel to the horizon located directly below the sun or moon.