EPOD - a service of USRA

The Earth Science Picture of the Day (EPOD) highlights the diverse processes and phenomena which shape our planet and our lives. EPOD will collect and archive photos, imagery, graphics, and artwork with short explanatory
captions and links exemplifying features within the Earth system. The
community is invited to contribute digital imagery, short captions and
relevant links.


Snowflake Sampler

January 27, 2020

6 Flocons-
Photographer: Daniel Leclerc
Summary Author: Daniel Leclerc

These lovely, dentritic snow crystals were collected near my home
in Montreal, Quebec, Canada. The temperature was 32 F (0 C) when I took
these images, on January 4, 2020. Though nearly all snow crystals
are hexagonal, how they grow depends on temperature and humidity.

The six-sided symmetry in a snowflake arises from the arrangement
of water molecules in the ice lattice. However, because the six
branches are growing independently of each other, whether the shape is
plate-like or pencil-like, snowflakes aren’t necessarily symmetrical.

Photo Details: Camera: Canon SX60 HS; F/3.4; ISO1600; 0.6 sec.
exposure.
* Montreal, Quebec Coordinates: 45.5017, -73.5673

Related EPODs

Snowflake Sampler Archive - Explaining Ring Patterns in a
Frozen Puddle Encore - Snow Eyes Icy Drops Snow Blankets
Joshua Tree National Park Encore - Lake Michigan Ice Cave
More...

Cryosphere Links

* Guide to Frost
* What is the Cryosphere?
* Bentley Snow Crystals
* Glaciers of the World
* Ice, Snow, and Glaciers: The Water Cycle
* The National Snow and Ice Data Center Google Earth Images
* Snow and Ice Crystals

-
Earth Science Picture of the Day is a service of the Universities
Space Research Association.

https://epod.usra.edu

--- up 5 days, 15 hours, 4 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)

EPOD - a service of USRA

The Earth Science Picture of the Day (EPOD) highlights the diverse processes and phenomena which shape our planet and our lives. EPOD will collect and archive photos, imagery, graphics, and artwork with short explanatory
captions and links exemplifying features within the Earth system. The
community is invited to contribute digital imagery, short captions and
relevant links.


Mulaku Atoll, Maldives

February 27, 2020

Meemu_island (003)

Photographer: Martin Dietzel
Summary Author: Martin Dietzel

The photo above was captured on my return flight home after a short
holiday on the Maldives, just north of the equator in the
Indian Ocean. Seeing the atolls, reefs and islands from
high above was unforgettable. When passing by the uninhabited island of
Raabondhihuraa, in the ring of the Mulaku Atoll (also known as
Meemu), for a brief moment a fragment of a rainbow appeared. With
sea level around the Maldives rising, it’s unclear what the future
holds for these beautiful but low-lying, fragile islands. Photo taken
on September 30, 2019.
* Mulaku Atoll, Maldives Coordinates: 3.016667, 73.466667

Related EPODs

Mulaku Atoll, Maldives Crescent Moon and Jupiter Conjunction
Above Evia Island, Greece Archive - Petrified Forest of Theodore
Roosevelt National Park Archive - Bird Rock in Chiricahua National
Monument São Miguel Island and Santa Iria Vista Julia Pfeiffer
Burns State Park
More...

Geography Links

* Atlapedia Online
* CountryReports
* GPS Visualizer
* Holt Rinehart Winston World Atlas
* Mapping Our World
* Perry-Castañeda Library Map Collection
* Types of Land
* World Mapper

-
Earth Science Picture of the Day is a service of the Universities
Space Research Association.

https://epod.usra.edu

--- up 5 weeks, 1 day, 15 hours, 5 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)

EPOD - a service of USRA

The Earth Science Picture of the Day (EPOD) highlights the diverse processes and phenomena which shape our planet and our lives. EPOD will collect and archive photos, imagery, graphics, and artwork with short explanatory
captions and links exemplifying features within the Earth system. The
community is invited to contribute digital imagery, short captions and
relevant links.


Frost Crystals on Airplane Window

March 27, 2020

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Photographer: Kevin Saragozza
Summary Authors: Kevin Saragozza; Jim Foster

The photo above shows frost crystals on an airplane window that I
observed a few weeks ago on a flight from the Canary Islands (Spain) to
Rome, Italy. Ice flowers such as this will form on a windowpane if
the outer plate is exposed to very cold temperatures (-40 F or -40 C is
not unusual at flight altitude) and sufficient moisture is available to
crystalize onto the surface. These crystals are in between the
windowpanes -- airplane windows generally consist of three acrylic
panes.

Note the circular symmetry of the crystals about the small
hole. This breathing hole is on all commercial airplane windows. It’s
an engineering feature designed to address differences between the low
atmospheric pressure outside of the window and the much higher pressure
on the inside of the window. The hole also serves to help prevent the
buildup of moisture between the windowpanes. Photo taken on February
22, 2020.

Photo Details: Camera: HUAWEI LLD-L31; Exposure Time: 0.0026s (1/386);
Aperture: ƒ/2.2; ISO equivalent: 50; Focal Length (35mm): 26.

Related EPODs

Frost Crystals on Airplane Window Rainbow Closeup on Evia
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Atmospheric Effects Links

* Atmospheric Optics
* Color and Light in Nature
* The Colors of Twillight and Sunset
* Refraction Index
* Image Gallery: Atmospheric Effects
* What is a Rainbow?

-
Earth Science Picture of the Day is a service of the Universities
Space Research Association.

https://epod.usra.edu

--- up 9 weeks, 2 days, 14 hours, 5 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)

EPOD - a service of USRA

The Earth Science Picture of the Day (EPOD) highlights the diverse processes and phenomena which shape our planet and our lives. EPOD will collect and archive photos, imagery, graphics, and artwork with short explanatory
captions and links exemplifying features within the Earth system. The
community is invited to contribute digital imagery, short captions and
relevant links.


Encore - Diatom Colony

June 27, 2020

Diatom colony_licmophora flabellata 080414 46 comp (3) 12in 3

August 2014 Viewer's Choice Today and every Saturday Earth Science
Picture of the Day invites you to rediscover favorites from the past.
Saturday posts feature an EPOD that was chosen by viewers like you in
our monthly Viewers' Choice polls. Join us as we look back at these
intriguing and captivating images.

Photographer: John Stetson
Summary Author: John Stetson
As this little colony of diatoms illustrates, even the simplest of
life forms at the bottom of the food chain can organize in
beautiful ways. These aquatic, photosynthetic plants are about
the width of a human hair in diameter -- approximately 100
microns. Diatoms are important in oxygen production, in
producing carbon sinks and are also a crucial food source for
krill. They first appeared in the fossil record some 144
million years ago, during the Jurassic Period. Photo taken in South
Portland, Maine on August 4, 2014.
* South Portland, Maine Coordinates: 43.64, -70.242

Related EPODs

Encore - Diatom Colony Superb Camouflage of the Crab Spider
Magpie Feather Coloration Wild Horses Along the Pony Express
Trail Encore - Bee in Amber Encore - Phaeocystis Suspended In a
Drop of Sea Water
More...

Animal Links

* Animal Diversity Web
* ARKive
* BirdLife International
* Bug Guide
* Discover Life
* Integrated Taxonomic Information System
* Microbial Life Resources
Earth Science Picture of the Day is a service of the
-
Universities Space Research Association.

https://epod.usra.edu

--- up 22 weeks, 3 days, 16 hours, 4 minutes
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EPOD - a service of USRA

The Earth Science Picture of the Day (EPOD) highlights the diverse processes and phenomena which shape our planet and our lives. EPOD will collect and archive photos, imagery, graphics, and artwork with short explanatory
captions and links exemplifying features within the Earth system. The
community is invited to contribute digital imagery, short captions and
relevant links.


Sass da Preja Buia

July 27, 2020

Capture
Photographer: Michela Meda
Summary Author: Michela Meda

Shown above is the Sass da Preja Buia, a large, erratic
serpentinite boulder found to the northwest of Sesto Calende Italy,
in the province of Varese. It dates back to the Quaternary Period,
likely the most recent (last) glaciation. A glacier, in its
retreat, dragged both moraine material and large boulders which,
like this one, slipped up to its present location from the Val
d'Ossola. In historical times, it’s thought that the Sass da Preja Buia
was used as a sacrificial altar. Because of both its historical and
geological significance, this green-colored erratic is designated as
one of the natural monuments of the Varese area. Photo taken on June
30, 2019.

Photo Details: Pentax K5 camera; 18/55 mm at 20mm; f/11; ISO 200; 1/60
sec. exposure.
* Sesto Calende, Italy Coordinates: 45.7307, 8.6366

Related EPODs

Sass da Preja Buia Archive - Concretions Archive - Diamond
Hunt Archive - Gneiss and Sandstone Layers Encore - Bowling
Ball Beach The Beaver's Tale
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Geology Links

* Earthquakes
* Geologic Time
* Geomagnetism
* General Dictionary of Geology
* Mineral and Locality Database
* Mohs Scale of Mineral Hardness
* This Dynamic Earth
* USGS
* USGS Ask a Geologist
* USGS/NPS Geologic Glossary
* USGS Volcano Hazards Program

-
Earth Science Picture of the Day is a service of the Universities
Space Research Association.

https://epod.usra.edu

--- up 1 week, 4 days, 15 hours, 25 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)

EPOD - a service of USRA

The Earth Science Picture of the Day (EPOD) highlights the diverse processes and phenomena which shape our planet and our lives. EPOD will collect and archive photos, imagery, graphics, and artwork with short explanatory
captions and links exemplifying features within the Earth system. The
community is invited to contribute digital imagery, short captions and
relevant links.


The Sun’s Green Rim Observed from Arroyo de San Serván, Spain

August 27, 2020

6a0105371bb32c970b026bde8a8364200c

Photographer: Juan Manuel Pérez Rayego
Summary Authors: Juan Manuel Pérez Rayego; Jim Foster

The photo above showing the green rim of the Sun’s trailing rim
was captured at sunset from Arroyo de San Serván, Spain. As the Sun
sets, if atmospheric conditions are favorable (relatively clear and not
optically thick), there’s a chance you might detect an
emerald-colored lining on the Sun’s upper rim. This occurs because when
the Sun is near the horizon the atmosphere can behave like a prism
and as a result sunlight is separated into different colors. However,
the green rim is best seen when the Sun is actually a degree or two
above the horizon. Note that the wind turbine silhouetted against
the Sun’s disk is in Portalegre, Portugal, about 57 miles (92 km) away
from my location. Always use caution when looking toward the Sun.
Photo taken on June 14, 2020.

Photo Details: DSLR (x1.6) + 400 mm; f / 5.6; 1/1250 sec. exposure; ISO
100.
* Arroyo de San Serván, Spain Coordinates: 38.8540, -6.4530

Related EPODs

The Sun’s Green Rim Observed from Arroyo de San Serván, Spain
Noctilucent Clouds Observed from Paris, France Archive -
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Dehradun, India Spray Droplets and Rainbow Colors
More...

Atmospheric Effects Links

* Atmospheric Optics
* Color and Light in Nature
* The Colors of Twillight and Sunset
* Refraction Index
* Image Gallery: Atmospheric Effects
* What is a Rainbow?

-
Earth Science Picture of the Day is a service of the Universities
Space Research Association.

https://epod.usra.edu

--- up 2 days, 20 hours, 23 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)

EPOD - a service of USRA

The Earth Science Picture of the Day (EPOD) highlights the diverse processes and phenomena which shape our planet and our lives. EPOD will collect and archive photos, imagery, graphics, and artwork with short explanatory
captions and links exemplifying features within the Earth system. The
community is invited to contribute digital imagery, short captions and
relevant links.


EPOD 20th - Lake Michigan Ice Balls Recurrence

September 27, 2020

EPOD 20th - Lake Michigan Ice Balls Recurrence
KAScott_20140101_6598-Msn We’re celebrating 20 years of Earth
Science Picture of the Day during the month of September! Today’s photo
features a popular EPOD from the past. Thanks to all of our followers
(on the blog, Facebook, Instagram and Twitter) for supporting us.
Thanks also to all of you who’ve submitted your photos. We’re most
appreciative. This EPOD was originally published February 4, 2014.

Photographer: Ken Scott
Summary Author: Ken Scott
Ferbuary 2014 Viewer's Choice The photo at top shows a crop of ice
balls just deposited from the frigid waters of Lake Michigan during
the polar vortex event of January 6-8. These nearly spherical
concretions accumulated along Sleeping Bear Dunes National
Lakeshore, on the northeastern shore of Lake Michigan. The ones
featured here are somewhat smaller than the basketball-sized spheres
that blanketed the shore last winter.
Ice balls form where water turbulence breaks up a layer of slush.
Click here for animation. Slushy ice mattes and frazil ice
accrete in the wind-whipped supercooled water. The mattes
eventually form into rounded lumps and will continue to grow until big
waves push them on shore or until they end up in a protected inlet -
photo at left.

Photo Details: Camera: NIKON D600; Lens: 24.0-85.0 mm f/3.5-4.5; Focal
Length: 28.0mm (35mm equivalent: 28mm); Aperture: f/11.0; Exposure
Time: 3.000 s; ISO equiv: 800; Software: Photomatix Pro 5.0.
* Sleeping Bear Dunes National Lakeshore, Michigan Coordinates:
44.913056, -86.020278

Related EPODs

EPOD 20th - Lake Michigan Ice Balls Recurrence EPOD 20th - Hair
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Pass and Hanging Valley Freshwater Over-layering Saltwater
More...

Cryosphere Links

* Guide to Frost
* What is the Cryosphere?
* Bentley Snow Crystals
* Glaciers of the World
* Ice, Snow, and Glaciers: The Water Cycle
* The National Snow and Ice Data Center Google Earth Images
* Snow and Ice Crystals

-
Earth Science Picture of the Day is a service of the Universities
Space Research Association.

https://epod.usra.edu

--- up 4 weeks, 5 days, 20 hours, 20 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)

EPOD - a service of USRA

The Earth Science Picture of the Day (EPOD) highlights the diverse processes and phenomena which shape our planet and our lives. EPOD will collect and archive photos, imagery, graphics, and artwork with short explanatory
captions and links exemplifying features within the Earth system. The
community is invited to contribute digital imagery, short captions and
relevant links.


Sunrise over the Sierra Nevada Mountains

October 27, 2020

Capture

Photographer: Cindy Todd
Summary Author: Cindy Todd

Shown above is the amazing coloration of the Sierra Nevada range,
the Alabama Hills area and Mount Whitney (seen in the
background at right center, 14,505 ft or 4,421 m) I observed during
sunrise one day this past summer. The pink and orange hues of the
rock slopes were captivating. Though technically from the same
formation as the Sierra Nevada, the Alabama Hills are composed of
eroded granite ( monzogranite and metamorphosed volcanic
rock) that date from 85-200 million years ago.

This area of the Sierra range is my favorite place to camp primarily
due to the exquisite views that greet you as the Sun rises each
morning. Additionally, you’re able to experience the desert and the
mountain in a single trip. I literally walked across the desert and up
the Sierra range, hiking almost 3,000 feet (914 m) in elevation in just
4 miles (6.5 km). Initially, I saw cacti, lizards, and desert flowers,
and then after walking perhaps a mile, I was beneath a canopy of pine
trees, watching butterflies and jays, with a waterfall in the distance.
It’s such a great area to explore! Photo taken on July 7, 2020.

Photo Details: Camera NIKON COOLPIX L610; Exposure Time 0.0050s
(1/200); Aperture ƒ/4.2; ISO equivalent 125; Focal Length (35mm) 54
* Lone Pine, California Coordinates: 36.6060, -118.0629

Related EPODs

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Wilderness Mushrooms Cerro Tomolasta and Cloud Shapes Olympic
Peninsula Bluff and Beach The Dolomites World Natural Heritage Area
Sleeping Giants, Mount Arenal and Cerro Chato
More...

Geography Links

* Atlapedia Online
* CountryReports
* GPS Visualizer
* Holt Rinehart Winston World Atlas
* Mapping Our World
* Perry-Castañeda Library Map Collection
* Types of Land
* World Mapper

-
Earth Science Picture of the Day is a service of the Universities
Space Research Association.

https://epod.usra.edu

--- up 9 weeks, 20 hours, 20 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)