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 - Geminid Meteors Observed Over Leiria, Portugal

February 01, 2020

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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: Carlos Dias
Summary Author: Carlos Dias

April 2014 Viewer's Choice The photo composite above shows meteors
showering an old windmill situated in the village of Outeiro,
Leiria, Portugal. These are from the Geminid meteor shower,
one of our most reliable, late-year meteor showers. According to the
International Meteor Organization, 110 meteors per hour were
recorded at the peak of the Geminids on December 13/14, 2013. However,
only viewers in very dark locations could observe this many falling
stars. My friend, Joao Almeida, and I counted approximately 70
meteors in the hours after midnight and before dawn on December 14,
2013.
Every year in early-mid December our planet crosses the orbital
path of asteroid 3200 Phaethon. Debris from this mysterious
body is vaporized as it bombards the Earth's upper atmosphere at
speeds of over 80,700 mph (130,000 km/h). The resulting meteors seem to
radiate from the constellation of Gemini. Note Orion at
lower right. Sirius is the very bright star just to the right of
the windmill. The Lyrids meteor shower peaks April 22. Look also
for the Eta Aquarids on May 5-7.
Photo Details: The photo is a combination of 7 photos, taken between
2:00 a.m. and 6:00 a.m. on December 14, 2013. Camera: Canon EOS REBEL
T2i; Software: Adobe Photoshop Lightroom 5.3 (Windows).
* Outeiro, Portugal Coordinates: 39.963880, -8.469503

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Encore - Geminid Meteors Observed Over Leiria, Portugal Star
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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

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

https://epod.usra.edu

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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.


Archive - 60 Years Ago Today on Bikini Atoll

March 01, 2020

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Each Sunday we present a notable item from our archives. This EPOD was
originally published March 1, 2014.

Image: Earth Observatory, Landsat OLI
Summary Author: David K. Lynch
Bikini_detail copy On March 1, 1954, the United States detonated a
thermonuclear hydrogen bomb on Bikini Atoll (above) in the
Marshall Islands. Code-named Castle Bravo, the 15 megaton
(MT) explosion blew a crater (left) in the island’s coral roughly
6500 ft in diameter and 250 ft deep (2000 m by 76 m). The resulting
mushroom cloud ultimately reached a height of 130,000 ft (40,000
m), well into the stratosphere. Castle Bravo was the largest
above-ground H-bomb test ever conducted by the US.
H-bomb energy is obtained by fusion, where two isotopes combine
(fuse) to form a third, and in the process release energy. In the case
of Castle Bravo, tritium released as lithium fissions (splits)
combines with deuterium and produces energetic, fast-moving
atomic particles and X-rays that are immediately absorbed by
surrounding material, thereby heating it. Rapid expansion of the
multimillion degree detonation products is the source of the blast
wave. All stars including our Sun are powered by fusion
reactions in their cores.
Castle Bravo was originally intended to be 4-6 MT but owing to
incomplete (at the time) knowledge about how lithium isotopes absorb
neutrons, the blast was much larger than anticipated. The unexpectedly
large neutron flux that occurred when lithium-7 decayed caused
uranium-235, one of the bomb’s components, to fission (split)
and release additional energy.
The surprisingly large detonation and unanticipated winds spread
radioactive fallout over a much larger area than expected. A number
of Marshallese, Japanese and American people received high radiation
doses and one died soon after exposure. It seems likely that more
delayed deaths and health problems have occurred as a result of fallout
from Castle Bravo. The incident provoked an international outcry, and
in 1963 the US, Great Britain and the Soviet Union signed the
Nuclear Test Ban Treaty prohibiting surface tests in the future.
* Bikini Atoll, Marshall Islands Coordinates: 11.697106,
165.271868

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Archive - 60 Years Ago Today on Bikini Atoll Archive - Carnac
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The Harod River and Eastern Roman Bridge Excavation of the
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History Links

* Paleoclimatology Data
* USGS: Age of the Earth
* What is Geologic Time?
* GSA Geologic Time Scale
* Earth Facts
* Earth History Courses

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

https://epod.usra.edu

--- up 5 weeks, 4 days, 15 hours, 5 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.


Pac-Man Crop Circle

April 01, 2020

PacMan Crop Circle
Photographer: Patrick Wiggins
Summary Author: Patrick Wiggins

Flying near Utah Lake (Utah) a few weeks back, I noticed this weird
crop circle. It reminded me of the Pac-Man game from years ago.
I observed it from the open window of a small aircraft flying
approximately 1,000 m above the surface. Most of these circles have
diameters of about 800 m, but this one has a huge bite taken out of it.

With central pivot irrigation, water is withdrawn from a single
well in the center of a field, and the crop (likely in this case to be
alfalfa or a feed crop of some kind) is watered as the pivot
rotates around it, allowing the water to be evenly distributed.
Moreover, less water is lost to evaporation with this method. Photo
taken on February 4, 2020.
* Utah Lake, Utah Coordinates: 40.172840,-111.944590

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Lake Powell Encore - Angel Falls Archive - Catastrophic Damage
During the Colorado Front Range Flood of September 11-13, 2013
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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

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

https://epod.usra.edu

--- up 10 weeks, 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.


The Stone Face of the Uinta Mountains

July 01, 2020

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RayB_duchesneface955c_25may20 (003)

Photographer: Ray Boren
Summary Author: Ray Boren

Poised above a winding Utah forest road, as well as the North Fork of
the Duchesne River, is a massive limestone outcrop that looks —
to those with a sense of pareidolia — very much like a gigantic
human head. Passersby might even imagine the craggy, squinting Stone
Face, illustrated in the first photograph here, taken on May 25, 2020,
to be a remnant and reminder of a lost civilization.

Pareidolia is the term used to describe our tendency to see images and
patterns, such as faces and bodies and other shapes, in inanimate
nature. Think of the fluffy poodle-clouds of a summer sky, or the
clouds in songwriter Joni Mitchell’s “ Both Sides Now,” a song made
famous by singer Judy Collins in the late 1960s. Or consider
psychologist Hermann Rorschach’s inkblot tests — and the good
old pareidolic Man in the Moon.

This particular Stone Face is in the southwestern Uinta Mountains,
northwest of the tiny Tabiona Valley town of Hanna and below majestic
cliffs of Mississippian Deseret Limestone. It’s about 3.5 miles
north of the intersection of Duchesne County Road 7 and Utah S.R.
35. The layered sedimentary rock, found in several Utah ranges,
formed about 340 million years ago in Panthalassa, the single
superocean that surrounded the supercontinent Pangaea. The
limestone was eventually thrust upward about 50 to 70 million
years ago, during the Laramide Orogeny, the mountain-building
episode that created the east-west trending Uinta Mountains and other
ranges. Shown in the bottom photo is the North Fork Duchesne River
(pronounced Dew-shayne) that courses through a classic U-shaped
canyon repeatedly carved and eroded during the glaciations of the
Pleistocene ice ages. At upper right is the left side of the Stone
Face.

Photo Details: Top - Camera: NIKON D3200; Exposure Time: 0.0050s
(1/200); Aperture: ƒ/10.0; ISO equivalent: 400; Focal Length (35mm):
120. Bottom: same except - Exposure Time: 0.0025s (1/400); Aperture:
ƒ/11.0; Focal Length (35mm): 24.
* Uinta Mountains, Utah Coordinates: 40.8827 -109.2971

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The Stone Face of the Uinta Mountains Encore - Position of the
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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 23 weeks, 16 hours, 5 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.


Encore - Smoking Mountain Lava Lake

August 01, 2020

Erta ale

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: Carlo Dellarole
Summary Author: Carlo Dellarole

September 2012 Viewer's Choice Seen above is a lava lake in the
caldera of Erta Ale Volcano. Erta Ale volcano (meaning
Smoking Mountain in the local Afar language) is located in the
Danakil depression of the Afar Triangle, in the northeastern
region of Ethiopia. It's one of the four active volcanoes which
occasionally generate a lava lake (the others are Kilauea,
Erebus and Nyiragongo).
Erta Ale Range is situated along the northern branch of the
African Rift and outlines an extraordinary geodynamic context,
showing a portion of mid-ocean ridge rising to the Earth's
surface. This process occurs along divergent boundaries, where two
plates are moving apart: in this case, the Arabian plate moving
eastwards and the African plate westwards.

Photo Details: Camera: Canon EOS 500D; Lens: EF-S10-22mm f/3.5-4.5 USM;
Focal Length: 10mm; Focus Distance: 4.29m; Aperture: f/3.5; Exposure
Time: 0.040 s (1/25); ISO equiv: 200; Software: Adobe Photoshop CS6
(Windows).
* Erta Ale Volcano, Ethiopia Coordinates: 13.6051, 40.66128

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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

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

https://epod.usra.edu

--- up 2 weeks, 2 days, 15 hours, 25 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.


EPOD 20th - Bisti Wilderness Mushrooms

October 01, 2020

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Bisti0171c_14oct19

January 2020 Viewer's Choice We’re celebrating 20 years of Earth
Science Picture of the Day during the month of September...and more,
there are just too many to fit into 30 days! 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 January 9, 2020.

Photographer: Ray Boren
Summary Author: Ray Boren

Those venturing into northwestern New Mexico’s stark
Bisti/De-Na-Zin Wilderness can be forgiven for feeling like an
incarnation of English writer Lewis Carroll’s (aka Charles Lutwidge
Dodgson) beloved Alice. Hikers find themselves trekking through a
virtually trailless, hoodoo-strewn desert — often encountering
eroded, stone-capped formations, many of which look very much like
hefty, lithified mushrooms. These, however, lack a hookah-smoking
caterpillar like the one illustrator John Tenniel depicted in
Carroll’s 1865 fantasy, “ Alice’s Adventures in Wonderland.”

In the first photograph here, taken on October 15, 2019, one such hiker
makes her way through a maze of Bisti hoodoos sometimes dubbed
“Mushroom City.” In a second photo, taken the previous evening, on
October 14, 2019, a lone hoodoo casts a mushroom-like shadow as the
setting Sun illuminates the landscape.

The Bureau of Land Management, which oversees the 45,000-acre
(18,211-hectare) wilderness, set aside by the U.S. Congress in 1984 on
the fringe of the Navajo Reservation, describes the combined
western Bisti and eastern De-Na-Zin badlands as a fantastic landscape
of strange rock formations, some bearing fossils. Weathering and
erosion have carved interbedded sedimentary layers of
sandstone, limestone, shale, mudstone, silt,
lignite coal and volcanic ash into hoodoos and other shapes.
The sediments were laid down up to 70 million years ago in a river
delta that fed into North America’s Western Interior Seaway, as
well as swamps and ponds.

The word Bisti derives from a Navajo language description (Bistahí)
of the shale, or adobe, hills. De-Na-Zin is from the Navajo for
standing cranes, depicted on a petroglyph panel. The hills, bluffs,
cliffs and outcrops range in color from predominant shades of gray and
tan to red, purple, black and off-white. Besides mushrooms, several
miles into the badlands visitors encounter other odd, and sometimes
towering, pinnacles and spires, often topped by erosion-resistant
cap rocks. Some feature gravity-defying cantilevered wings. There
are also arches and windows, petrified logs, alien eggs —
and, as some describe it: a dragon’s head.

Photo Details: Top - Camera: NIKON D3200; Exposure Time: 0.0020s
(1/500); Aperture: ƒ/11.0; ISO equivalent: 250; Focal Length (35mm):
24. Bottom - same except: Exposure Time: 0.0040s (1/250); Aperture:
ƒ/10.0; ISO equivalent: 400; Focal Length (35mm): 28.
* Bisti/De-Na-Zin Wilderness, New Mexico Coordinates: 36.2921,
-108.1298

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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

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