atomstargazer:

What causes rainbow-colored clouds?

Sky watchers on occasion report seeing colors in the clouds, and sometimes our friends send photos of these rainbow-like clouds. You’ll find some examples below. These colorful clouds are called iridescent clouds, and the phenomenon is called cloud iridescence or irisation. The term comes from Iris, the Greek personification of the rainbow. When you see a cloud like this, you know there are ice crystals or small water droplets in the air. Larger ice crystals produce solar or lunar halos, but tiny ice crystals or water droplets cause light to be diffracted – spread out – creating this rainbow-like effect in the clouds.

Sky watchers on occasion report seeing colors in the clouds, and sometimes our friends send photos of these rainbow-like clouds. You’ll find some examples below. These colorful clouds are called iridescent clouds, and the phenomenon is called cloud iridescence or irisation. The term comes from Iris, the Greek personification of the rainbow. When you see a cloud like this, you know there are ice crystals or small water droplets in the air. Larger ice crystals produce solar or lunar halos, but tiny ice crystals or water droplets cause light to be diffracted – spread out – creating this rainbow-like effect in the clouds.

Read more about iridescent clouds on Les Cowley’s great website Atmospheric Optics

Galaxy Cove Vista 

Image Credit & Copyright: Rogelio Bernal Andreo (Deep Sky Colors)

“To see a vista like this takes patience, hiking, and a camera. Patience was needed in searching out just the right place and waiting for just the right time. A short hike was needed to reach this rugged perch above a secluded cove in Julia Pfeiffer Burns State Park in California, USA. And a camera was needed for the long exposure required to bring out the faint light from stars and nebula in the background Milky Way galaxy. Moonlight and a brief artificial flash illuminated the hidden beach and inlet behind nearby trees in the above composite image taken about two weeks ago. Usually obscured McWay Falls is visible just below the image center, while the Pacific Ocean is in view to its right.”

Sunsets, Dancing Auroras, Eclipses, Sun Trails & Comets - Mesmerizing Sky Photography of Juan Carlos Casado — Tierra y Estrellas

(Source: kenobi-wan-obi)

The Big Dipper 

Image Credit & Copyright: Jerry Lodriguss (Catching the Light)

“Do you see it? This common question frequently precedes the rediscovery of one of the most commonly recognized configurations of stars on the northern sky: the Big Dipper. This grouping of stars is one of the few things that has likely been seen, and will be seen, by every generation. The Big Dipper is not by itself a constellation. Although part of the constellation of the Great Bear (Ursa Major), the Big Dipper is an asterism that has been known by different names to different societies. Five of the Big Dipper stars are actually near each other in space and were likely formed at nearly the same time. Connecting two stars in the far part of the Big Dipper will lead one to Polaris, the North Star, which is part of the Little Dipper. Relative stellar motions will cause the Big Dipper to slowly change its apparent configuration over the next 100,000 years.”

Waterfalls, Auroras, Comet: Iceland 

Image Credit & Copyright: Stephane Vetter (Nuits sacrees)

“If not distracted by the picturesque landscape, waterfalls, stars, and auroras, you might be able to find Comet PANSTARRS. The above image, capturing multiple terrestrial and celestial wonders in a single shot, was taken last week in southwest Iceland. The popular Gullfoss waterfalls are pictured under brilliant auroras that followed a M1-class solar flare and powerful Coronal Mass Ejection two days earlier. Give up on locating the comet? Comet PANSTARRS is faintly visible as a light blip just above the horizon toward the left of the above image. The comet remains more directly visible to northern observers with binoculars looking toward the western sky just after sunset.”

beben-eleben:

Why is the sky blue?

PanSTARRS from France 

Image Credit & Copyright: Jean-Luc Dauvergne

“Still looking for that comet? Comet PanSTARRS (C/2011 L4) naked-eye appearance in the northern hemisphere is described by successful comet spotters as a dim star with faint a tail. If you want to catch it the next few days could be your best bet. Start looking low and almost due west about 45 minutes after sunset. Of course, clear skies and a pair of binoculars should help a lot. Sky photographer Jean-Luc Dauvergne found suitable weather and western horizon for this comet and crescent Moon portrait after a road trip on March 13. Seeing PanSTARRS for the first time, he recorded the beautiful twilight scene with a telephoto lens near historical Alesia in France.”

Twenty Four Hour View of the Sky by Chris Kotsiopoulos.

“After wondering for some time whether it was possible to image the sky from one morning to the next where I live in Athens Greece, I decided to give it a try. After hours of planning and preparation, and a full day of shooting, the image above is the result of this labor of love. It took me about 12 hours to pull together and process a single image that included over 500 star trails, 35 shots of the Sun and 25 landscape pictures. 

I began the shooting the morning of December 30, 2010, taking photos with my camera on a tripod facing east. The day portion of this shoot is composed of a dozen shots covering the landscape from east to west as well as the Sun’s course across the sky, from sunrise to sunset. I recorded the Sun’s position exactly every 15 minutes using an intervalometer, with an astrosolar filter adjusted to the camera lens. In one of the shots, when the Sun was near its maximum altitude, I removed the filter in order to capture a more dramatic shot that showed the Sun’s “glare.” After sunset, I took various shots with the camera facing west-northwest in order to achieve a more smooth transition from the day portion to the night portion of the image. The night portion is also composed of a dozen landscape shots but this time from west to east. After the transition” shots, I took a short star trail sequence of approximately half an hour duration, with the camera facing northwest. At 7:30, I turned the camera to the north and started taking the “all-night” star trail shots — lasting almost 11 hours. After accomplishing this, I then turned the camera to northeast and shot another short half an hour star trail sequence, and then finally, with the camera now facing east-northeast, I took a series of night-to-day transition shots.”

ilovecharts:

24 Hour Sky Ring

via xwidep: astudyinbowties: alexandrefelixdarnay: alexandreajewels: tennant-hair-porn:

I appreciated that sky post, I just didn’t appreciate how well it doesn’t work with tumblr because you just scroll forever and it never ends. So I just made it into a small circle to so you can enjoy it’s existence without freaking out over it trying to take over your dash

(Source: doctorwho-hair-porn, via scinerds)

Keep your eyes towards the moon. 

“Comet Pan-STARRS is just peeking into view in the western sky shortly after sunset. It will be close to the Moon on the evenings of March 12 and 13, making it easier to pick out. The comet is about 100 million miles from Earth, but closer to the Sun, which warms the big iceball, vaporizing some of its material and creating a long, glowing tail. “

Learn more about where and how to see the comet here and here.

(Source: stardate.org)

Comets Lemmon and PanSTARRS Peaking 

Image Credit & Copyright: Yuri Beletsky (ESO)

“Two impressive comets will both reach their peak brightness during the next two weeks. Taking advantage of a rare imaging opportunity, both of these comets were captured in the sky together last week over the Atacama desert in South America. Comet C/2012 F6 (Lemmon), visible on the upper left of the above image, is sporting a long tail dominated by glowing green ions. Comet C/2011 L4 (PanSTARRS), visible near the horizon on the lower right, is showing a bright tail dominated by dust reflecting sunlight. The tails of both comets point approximately toward the recently set Sun. Comet Lemmon will be just barely visible to the unaided eye before sunset in southern skies for the next week, and then best viewed with binoculars as it fades and moves slowly north. Comet PanSTARRS, however, will remain visible in southern skies for only a few more days, after which it will remain bright enough to be locatable with the unaided eye as it moves into northern skies. To find the giant melting snowball PanSTARRS, sky enthusiasts should look toward the western horizon just after sunset. Deep sky observers are also monitoring the brightening of Comet C/2012 S1 (ISON), which may become one of the brightest objects in the entire night sky toward the end of 2013.”

If you hover over the image here you can see it with and with out the labeled comets.

Asperatus Clouds Over New Zealand
Image Credit & Copyright: Witta Priester

“What kind of clouds are these? Although their cause is presently unknown, such unusual atmospheric structures, as menacing as they might seem, do not appear to be harbingers of meteorological doom. Known informally as Undulatus asperatus clouds, they can be stunning in appearance, unusual in occurrence, are relatively unstudied, and have even been suggested as a new type of cloud. Whereas most low cloud decks are flat bottomed, asperatus clouds appear to have significant vertical structure underneath. Speculation therefore holds that asperatus clouds might be related to lenticular clouds that form near mountains, or mammatus clouds associated with thunderstorms, or perhaps a foehn wind — a type of dry downward wind that flows off mountains. Such a wind called the Canterbury arch streams toward the east coast of New Zealand’s South Island. The above image, taken above Hanmer Springs in Canterbury, New Zealand, in 2005, shows great detail partly because sunlight illuminates the undulating clouds from the side.”

Fisheye view of the Southern Sky’s Milky Way and it’s constellations.

Credit: ESO/S. Brunier