CWL

Red Sprite Lightning with Aurora

What’s that in the sky? It is a rarely seen form of lightning confirmed only about 25 years ago: a red sprite.

Recent research has shown that following a powerful positive cloud-to-ground lightning strike, red sprites may start as 100-meter balls of ionized air that shoot down from about 80-km high at 10 percent the speed of light and are quickly followed by a group of upward streaking ionized balls.

The above image, taken a few days ago above central South Dakota, USA, captured a bright red sprite, and is a candidate for the first color image ever recorded of a sprite and aurora together.

Distant storm clouds cross the bottom of the image, while streaks of colorful aurora are visible in the background. Red sprites take only a fraction of a second to occur and are best seen when powerful thunderstorms are visible from the side.

Moon Halo over Halo Island

“The colorful 22-degree atmospheric halo of the moon is captured together with planets Venus and Jupiter over the strait of Hormuz in the Persian Gulf, Well known because of political tides over the middle east region.

The name Hormuz is an island in this area. Hormuz is a piece of Paradise, believed by local citizens of the island. The island has a historic castle and eye catching natural scenes, but nowadays most of the people doesn’t even know there is an island that the strait named after it; The island is faded in memories like a halo. The yellowish lights on the horizon belong to Qeshm island. While the week I was in Hormuz island I saw halo moon every night, considering high evaporation rate during days its not a hardly seen phenomenon in Hormuz.” — Mahdi Zamani

Lightning Under the Milky Way

“Lightnings And Stars At Lake Korission Corfu, Milkyway Galaxy: Photo of Milky Way at Mount of St. Matthew with magnificent view at lake Korrision, undr the storms at the back is the island of Paxos and the left Lightnings is hitting Preveza and the right lightning strikes at mount Enos of Kefalonia.” — B. Metellinos

Saturn Hurricane

Acquiring its first sunlit views of far northern Saturn late last year, the Cassini spacecraft’s narrow-angle camera recorded this stunning image of the vortex at the ringed planet’s north pole.

The false color, near-infrared image results in red hues for low clouds and green for high ones, causing the north-polar hurricane to take on the appearance of a rose.

Enormous by terrestrial hurricane standards, this storm’s eye is about 2,000 kilometers wide, with clouds at the outer edge traveling at over 500 kilometers per hour.

The north pole Saturn hurricane swirls inside the large, six-sided weather pattern known as the hexagon. Of course, in 2006 Cassini also imaged the hurricane at Saturn’s south pole.

Multiple Light Pillars

The multiple vertical shafts pictured above are light pillars.

Whereas Sun pillars can be observed on occasion near sunrise and sunset, when sunlight glints off the undersides of ice crystals in cirrus clouds, these pillars have another light source; highway and shopping mall lights. In this case, the artificial lighting is being reflected off diamond dust falling just above the surface.

Diamond dust is ice (ice crystals) that forms when the air is very cold and the lower atmosphere is quite stable. With this type of precipitation, accumulation is negligible since little moisture is squeezed out of the cold, dry atmosphere. The temperature when I took this shot was about - 4 F (- 20 C) Note that a light pillar’s color depends on the color of the artificial lighting.

Staring at Storms

Saturn’s richly dynamic atmosphere rewards viewers with unique and fascinating structures with every new look. Here, Cassini uses the near-infrared filters on its wide-angle camera to get a better look at some of Saturn’s cloud patterns, shaped by wind and storms in Saturn’s atmosphere.

Airglow

by Brian Larmay

Airglow (also called nightglow) is the very weak emission of light by a planetary atmosphere. In the case of Earth’s atmosphere, this optical phenomenon causes the night sky to never be completely dark (even after the effects of starlight and diffused sunlight from the far side are removed).[**]

Up Close and Personal With Titan’s Haze

This is an approximate true color image of Titan’s haze layers, taken by Cassini’s Imaging Science Subsystem during Cassini’s 91st encounter with Titan on April 5, 2013.

Image: NASA / JPL / SSI / composite by Val Klavans

Titan’s upper haze layers appear blue, while its main atmospheric haze appear orange in this view. The difference in color is most likely due to particle size rather than composition. The blue haze probably consists of smaller particles than the orange haze.

echopi:

The five major Ice Ages

The Ice Ages episode of In our Time with Melvyn Bragg (14 Feb 2013, 43 mins) discusses many fascinating concepts surrounding Earth’s glacial history and Climate Change. The most striking things to learn may be…

• There have been at least five major Ice Ages (or glaciations) in Earth’s history.
• Earth has been ice-free, even in the high latitudes, for about 85% of its history.
• The first Icehouse Earth occurred at about noon on the 24-hour geologic time scale (about 2.5Ba).
• The last Snowball Earth, where polar ice sheets grow and meet at the equator, occurred about 800Ma and ended with increasing CO2 caused by volcanism.
• The change into an ice age occurs gradually, when more snow falls than melts, rather than a sudden cold snap.

Our current Ice Age

• Our current geologic period, the Cenozoic era or the “Age of Mammals”, began 65Ma with the Cretaceous-Paleogene (K-Pg) extinction event.
• The current ice age, the Quaternary glaciation, beginning about 2.6Ma has featured 40K/100K year cycles of glacials/interglacials.
• The conditions needed to setup the current ice age took about 40M years, beginning with the thermal isolation of the Antarctic.
• The end of the current ice age will occur when the Greenland and Antarctic ice sheets melt. This will happen whether or not humans accelerate it.

Icehouse, Greenhouse, Snowball Earths

• An Icehouse Earth is one in which the global climate makes an ice age possible
• A Greenhouse Earth is one in which tropical temperatures may reach the poles
• A Snowball Earth is one where nearly the entire surface of the Earth is frozen

We gather data on climate change from not only geological strata, ice cores, and the atmosphere, but from the ocean floor, geochemistry, and other surprising chemical and archaeological relations as well as our understanding of the earth’s dynamics and kinematics.

The five major Ice Ages
	Ice Age	Million years ago (Ma)	% of Earth’s Age	Notes
I	Huronian	2,400-2,100	50%	Configuration of continents highly speculative
II	Cryogenian	850-635	83.5%	Snowball Earth, followed by Cambrian Explosion, first marine animals.
III	Andean‑Saharan	450-420	90.3%	First land plants, continued marine diversification.
IV	Karoo	360-260	93.1%	Land animal diversification, coal bed formation, followed by “Great Dying” (P-Tr) extinction event.
V	Quaternary	2.5	99.9%	Current Ice Age

Lake Powell Stormy Night

Storm clouds, lightening, and stars appear over Lake Powell, a reservoir on the Colorado River, straddling the border between Utah and Arizona. — Babak Tafreshi

sciencesoup:

The Ecosystem of Earth

Earth is a tiny thriving planet in a vast universe, sandwiched between two worlds gone wrong—Mars, which once had water but is now a dry and freezing desert, and Venus, which was once similar to Earth but is now swirling with boiling, toxic cloud. Spinning on between them is Earth: golden, ripe for life. It’s is not a cold, indifferent place—it’s an ecosystem, a sprawling network of interconnected life, and you are part of it. Humans can’t be separated from nature, because we are connected to every living thing. We were an accident, grittily surviving and branching out in the tree of evolution to become what we are today. We are dominating this ecosystem, and the consequences of our actions ripple out to affect every other living being on the planet—sometimes in a good way, sometimes in a bad way, but we don’t know how to balance. We search for life on other planets when we don’t even know how to look after our own. This is the only Earth we have, and perhaps it has created its own destruction.  Perhaps our ever-growing desire for technological advancement will bring about our own demise, our own extinction, in order to save the planet from ourselves—a Shakespearean tragedy on an immense scale. We are children of Earth, and we are killing it.

A Quadruple Lunar Halo Over Spain

Sometimes falling ice crystals make the atmosphere into a giant lens causing arcs and halos to appear around the Sun or Moon.

Image Credit & Copyright: Dani Caxete

This past Saturday night was just such a time near Madrid, Spain, where a winter sky displayed not only a bright Moon but as many as four rare lunar halos. The brightest object, near the top of the above image, is the Moon. Light from the Moon refracts through tumbling hexagonal ice crystals into a 22 degree halo seen surrounding the Moon.

Elongating the 22 degree arc horizontally is a circumscribed halo caused by column ice crystals. More rare, some moonlight refracts through more distant tumbling ice crystals to form a (third) rainbow-like arc 46 degrees from the Moon and appearing here just above a picturesque winter landscape.

Furthermore, part of a whole 46 degree circular halo is also visible, so that an extremely rare — especially for the Moon — quadruple halo was actually imaged. The snow-capped trees in the foreground line the road Puerto de Navacerrada in the Sierra de Guadarrama mountain range near Madrid. Far in the background is a famous winter skyscape that includes Sirius, the belt of Orion, and Betelgeuse all visible between the inner and outer arcs. Halos and arcs typically last for minutes to hours, so if you do see one there should be time to invite family, friends or neighbors to share your unusual lensed vista of the sky.

Bright Clouds on Uranus

The false colors in this image indicate altitude.

Credit: Erich Karkoschka (University of Arizona) and NASA

The green and blue regions show where the atmosphere is clear, allowing sunlight to penetrate deep into Uranus. In the yellow and gray regions, a haze or cloud layer is reflecting sunlight away. Orange and red colors indicate very high clouds, like cirrus clouds on Earth.

Before the Typhoon

On 27th July 2012, before the Saola typhoon approaching, the thunder and lightning is very powerful. I captured this photo in the Chuanfan Rock of Kenting National Park. — Chen Wei-Tsung