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.


Great Salt Lake’s Mirabilite Mounds

March 23, 2022

GSLmirabsalt876c_01feb22
GSLmirabsalt876c_01feb22

Photographer: Ray Boren

Summary Author: Ray Boren

Due to long-term drought, exposed shorelines of the Great Salt Lake
are in places speckled with crystalline hummocks that resemble the
larger terraced springs of Yellowstone National Park. Unlike the
national park’s travertine-lined hot springs, however, the Utah
phenomena are mirabilite mounds. These unique landforms take shape
over the cold winter months and when shoreline water has withdrawn
enough to reveal usually submerged springs.

This process has been the case for the past few years, notably on the
south shore beach at Great Salt Lake State Park and Marina, as
illustrated in the above photographs taken on February 1, 2022. The
first photo shows several mounds, with the lake’s edge and
Stansbury Island in the distance, while the second picture is a
closeup of one of the formations.

A layer of sodium sulfate underlies the lakebed surface, so when
spring water rises in the winter cold, mirabilite crystals effloresce
upon exposure. This crystallization process creates the mounds and
their sequences of small terraces. The mineral mirabilite — from the
Latin “sal mirabilis” for “wonderful salt” — is found in saline
lakes and on playas around the world. The rare mounds around Great Salt
Lake are not composed of sodium chloride, also known as common table
salt (NaCl), but instead of hydrated sodium sulphate
(Na2SO4•10H2O). This compound is also called Glauber’s salt and has
various medical applications.
* Great Salt Lake, Utah Coordinates: 41.115, -112.476

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Great Salt Lake’s Mirabilite Mounds La Cascata di Fondo and
Orion The Hunter Waterfall in the Desert Knik Arm Tides of
Alaska The Law of the (Colorado) River Utah’s Great Salt Lake
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Hydrology Links

* Current Sea Surface Temperature
* NOAA Ocean Explorer Gallery
* Ocean Color
* What is hydrology?
* Tides and Currents
* Water Resources of the United States
* World Waterfall Database
* The USGS Water Science School
* World Water Database
* The World’s Water
* USGS Surface Water Information Pages

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

https://epod.usra.edu

--- up 3 weeks, 2 days, 21 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.


Supernumerary Rainbow Over Modica, Italy

May 23, 2022

Arcobaleno_verticale_collage_epod

Photographer: Salvatore Cerruto

Summary Authors: Salvatore Cerruto; Cadan Cummings

During the afternoon of February 15, 2022, I was lucky enough to see a
supernumerary rainbow in the sky over Modica, Sicily, Italy.
These unique rainbow arcs are visible below the primary rainbow and
are produced when incoming sunlight is diffracted through very
small raindrops. Resulting from the diffraction process are regions of
light wave interference where the colorful band are from
constructive interference and the colorless gaps are from destructive
interference.

Supernumerary rainbows can be identified by several colored fringes-
ranging from indigo to green- visible below the rainbow that also
appear like the rainbow is repeating itself. To show the optical
phenomenon in greater detail, I enlarged the part that had the
supernumerary arcs and saturated it a little to highlight the
features and colors. This specific composite image is a panorama
composed of eight vertical shots taken using a Nikon DSLR camera with a
35mm lens.
* Modica, Sicily, Italy Coordinates: 36.8588, 14.7608

Related EPODs

Supernumerary Rainbow Over Modica, Italy Haleakala Shadow and
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Sundog over Camelot Colorful Lights and Calm Night in Sweden
Brocken Spectre Observed with Drone
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Atmospheric Effects Links

* Atmospheric Optics
* Optic Picture of Day: Gruppo Astrofili Galileo Galilei
* 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 12 weeks, 21 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.


Summertime Fireflies and Star Trails

August 23, 2022

DSC_1228s2

Photographer: Matthew Chin
Summary Author: Matthew Chin
Even though Hong Kong isn’t graced with many green spaces, in a few
locations, such as Sha Lo Tung, we can see vast numbers of
fireflies in late spring and throughout summer. Unfortunately,
their environment is being increasingly destroyed because of various
human activities. As shown above, the bioluminescent trails left by
the little fireflies and the star trails of the summer
constellations have been combined onto one image. Photo taken on August
29, 2017.

Photo details: Nikon D750 camera; 18 mm lens.


Sha Lo Tung, Hong Kong, Coordinates: 22.4794, 114.1823

Related EPODs

Summertime Fireflies and Star Trails Ancient Fossil Assemblage
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California Quail After a Snowstorm
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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 25 weeks, 1 day, 21 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.


Saturn's Rings in 2020, 2021 and 2022

November 23, 2022


Astro_by_sona (5)
Photographer: Sona Shahani
Summary Author: Sona Shahani

Shown above is a compilation of images featuring Saturn and its
ring system in 2020, 2021 and 2022. The most recent image was taken
on June 25, 2022. Saturn’s axial tilt is 27 degrees, and from our
perspective we see the rings present themselves differently every
year. Reflection from Saturn’s rings slightly increases how bright
Saturn appears to us. However, even when the “ringed planet” is at
maximum tilt, we’re unable to detect the rings with the naked eye. All
photos observed from New Delhi, India.

Photo details: 8" Skywatcher Flextube Dobsonian telescope; ZWO
ASI178MC; 2.5X; Televue Powermate; EQ Platform; SvBony UV/IR Filter;
Captured in Shaprcap; stacked in ASi3; Wavelets in Registax and fine
tuning in Photoshop.

New Delhi, India Coordinates: 28.6139, 77.2090


Related EPODs

Saturn's Rings in 2020, 2021 and 2022 What is the Color of the
Lunar Seas? Wafer Thin Moon and Pumpkin Sky Paraselene, Antares
and Supermoon Witches Broom in Cygnus Observing Six Major
Annual Meteor Showers
More...

Night Sky Links

* Space Weather Live
* Space Weather Live Forum
* About the Moon
* American Meteor Society
* Arbeitskreises Meteore e.V.
* Global City Lights
* Heavens Above Home Page
* The International Meteor Organization
* Lunar and Planetary Institute
* MoonConnection
* NASA Eclipse Web Page
* Understanding The Moon Phases

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

https://epod.usra.edu

--- up 38 weeks, 2 days, 21 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)