• ES Picture of the Day 09 2022

    From Black Panther@21:1/186 to All on Sun Jan 9 11:00:40 2022
    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 - Armorican Quartzite

    January 08, 2022
    6a0105371bb32c970b01bb0907d3b8970d

    Every weekend we present a notable item from our archives.

    This EPOD was originally published June 9, 2016.
    Photographer: June 2016 Viewer's Choice Carlos Gómez
    Summary Authors: Carlos Gómez; Jim Foster

    The photo above shows slabs of Armorican Quartzite rising from
    Cíjara Lake ( Embalse de Cíjara), near Cáceres, Spain. As shown
    here, Armorican Quartzite is formed of relatively light-colored,
    thick-bedded layers of quartzite or sandstone that may consist of
    gneisses, deformed tuff, arkose sandstone, and
    conglomerates. Cíjara Lake is actually a reservoir, a dammed
    portion of the Guadiana River, in the Toledo Mountains region
    of west-central Spain. Photo taken on May 23, 2016.

    Photo Details: Camera Model: Canon EOS 600D; Lens: EF-S18-55mm
    f/3.5-5.6 IS II; Focal Length: 37mm; Aperture: ƒ/6.3; Exposure Time:
    0.010 s (1/100); ISO equiv: 100; Software: Windows Photo Editor 10.

    * Cíjara Lake, Spain Coordinates: 39.378056, -5.012222

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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

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  • From Black Panther@21:1/186 to All on Wed Feb 9 11:01:20 2022
    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.


    Red Jellyfish Sprite Over Mediterranean Sea

    February 09, 2022

    GrosJellycarre_compress98

    Photographer: Arnaud Besançon

    Summary Authors: Arnaud Besançon; Cadan Cummings

    This breathtaking photo taken on the night of November 24, 2021,
    captures red “jellyfish” sprites as seen from the Grand Ballon
    mountain (4500 ft / 1400 m) in Eastern France. Grand Ballon translates
    “great round-topped mountain” and it is the tallest elevation in the
    Vosges. Sprites are electrical discharges that appear high in the
    atmosphere and are prompted by severe thunderstorm activity. The
    storm cells from which these sprites originated were located to our
    south over the Mediterranean Sea. With the help of Serge Soula from
    the Aerology Laboratory ( National Center for Scientific Research
    and Paul Sabatier University), both the distance and power of these
    sprites were able to be accurately determined. The event was generated
    by four parent arcs that were respectively 352, 363, 384, and 381 miles
    (567, 585, 618 and 614 km) away. Their power was also determined to
    vary with each emitting 61, 153, 62 and 44 kiloamperes. This specific
    storm cell was very intense, which likely explains why I had
    previously never captured so many sprites in one night!
    * Grand Ballon, Alsace, France Coordinates: 47.9010, 7.0982

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    * US National Weather Service

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

    https://epod.usra.edu

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  • From Black Panther@21:1/186 to All on Wed Mar 9 11:00:32 2022
    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.


    Ice Blade in Bucket

    March 09, 2022

    IceSail_20220111_083516 (003)

    Photographer: Pierre Renoult

    Summary Authors: Pierre Renoult; Jim Foster

    Imagine my surprise when one morning earlier this winter I found a
    large piece of ice protruding from a bucket of water left out overnight
    on the terrace of my home, in Aurillac, France. The day before it
    rained most of the day, and then the sky cleared allowing overnight
    temperatures to plummet below the freezing point. By the next morning,
    I couldn’t open my mailbox as it was frozen. This protrusion had an
    obvious slope and was about 16 inches (40 cm) in length.

    Once the sky cleared, fast freezing or “ supercooling” of the water
    in the bucket took place. When water is confined in small places, such
    as a pool or a bucket, the water freezes first along the edges and so
    water in the center is slightly raised with respect to the sides. As
    ice expands beneath the surface it forces out the remaining liquid
    through the hole at center. This is where the hollow ice blade emerged.
    Different shapes can be observed, including spikes, sails and
    needles. The size of the pool of water, just how it’s confined, and
    differential freezing rates all play a role in determining if
    protrusions will form and just what shape they'll take.

    It’s worth noting that because ice expands in crystalline planes,
    protrusions commonly occur at similar angles, typically about 60
    degrees to the ice-covered surface. If you have a frost-free
    freezer, maybe you've noticed that sharp spikes sometimes form on ice
    cubes. Photo taken on January 11, 2022.
    * Aurillac, France Coordinates: 44.9310, 2.4450

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    Cryosphere Links

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

    https://epod.usra.edu

    --- up 1 week, 2 days, 20 minutes
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  • From Black Panther@21:1/186 to All on Sat Apr 9 12:01:02 2022
    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 - Glacial Evidence in Central Park

    April 09, 2022

    6a0105371bb32c970b01b7c6def3d2970b

    Every weekend we present a notable item from our archives.

    This EPOD was originally published on September 25, 2014.

    Photographer: Bruce Gervais
    Summary Authors: Bruce Gervais; Jackie Phillips

    There's ample evidence of New York City’s glacial history
    throughout Central Park. The top photo shows two glacial
    erratics. These large boulders were transported by moving ice at the
    height of the Wisconsin glaciation, around 20,000 years ago. During
    this time the Laurentide ice sheet covered what is now New York
    City to a depth of about 1,000 ft (300 m). As the ice sheet flowed over
    the landscape it smoothed the bedrock through abrasion and
    plucked fragments of rock from the ground. These plucked fragments were
    incorporated into the base of the moving ice and transported by it.
    After the ice sheet melted, some 12,000 years ago, many fragments were
    scattered throughout the landscape.

    Nycglacialrock2

    The lower photo shows an elongated asymmetrical landform called a
    roche moutonnee. The axis of roches moutonnees indicates the
    direction of ice flow. In this photo, the ice flowed from left to
    right. These landforms are ubiquitous in the park and were cleverly
    incorporated into its design. Photo taken on July 22, 2014.

    Photo details: Top - Camera Maker: Panasonic; Camera Model: DMC-TS3;
    Focal Length: 4.9mm (35mm equivalent: 28mm); Aperture: f/3.3; Exposure
    Time: 0.0063 s (1/160); ISO equiv: 100. Bottom - same except: Focal
    Length: 8 mm; Aperture: f/4.5; Exposure Time: 1/80 s; ISO equiv: 160.
    Photo stitch program: Microsoft ICE.
    * Glacial Erratic, Central Park Coordinates: 40.769358, -73.975933

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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
    * MyShake - University of California, Berkeley
    * 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 5 weeks, 5 days, 21 minutes
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  • From Black Panther@21:1/186 to All on Mon May 9 12:01:08 2022
    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.


    Sun Pillar Reflection on the Holtsós Lagoon

    May 09, 2022

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    Photographer: Gianluca Lombardi

    Summary Authors: Gianluca Lombardi; Cadan Cummings

    The photo above taken on the Holtsós Lagoon in Southern Iceland
    highlights the calm wind moving across the water and a sun pillar
    on the horizon. Due to the calm waters, a reflection of the sun pillar
    is clearly visible on the lagoon along with the silhouette of the
    Vestmannaeyjar (Western Islands). A sun pillar is a form of optical
    phenomenon caused when hexagonal shaped ice crystals suspended in
    the atmosphere are oriented horizontally and reflect incoming sunlight
    toward an observer. Pillar hue can vary based on environmental
    conditions, such as cloud cover and Sun color. The silence and
    calm made everything very surreal.
    * Holtsós Lagoon, Iceland Coordinates: 63.5370, -19.7494

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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, 21 minutes
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)
  • From Black Panther@21:1/186 to All on Thu Jun 9 12:01:06 2022
    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.


    Rainbow Flashes

    June 09, 2022

    Rainbow Flahes on Dschubba and Mars

    Photographer: Dario Giannobile

    Summary Author: Dario Giannobile

    This photo compilation features an optical effect called Green
    Flash for the planet Mars and star Dschubba. Green ray is a
    phenomenon caused by the refraction of incoming light as it passes
    through thick layers of the atmosphere. Shorter wavelengths refract
    more strongly than longer red wavelengths, and color separation gives a
    green hue to the last visible ray of our luminous object. Green ray
    evidence is extremely common on the solar disk but much rarer on the
    Moon and planets. Even more peculiar is a separation of the light
    that can lead to the observation of a blue-tinted flash. A
    telescope or telephoto lens and camera can help capture this
    tantalizing result of atmospheric refraction when celestial bodies are
    close to the horizon. This one-of-a-kind image shows for the first time
    the phenomenon in its entirety during the rising of the star Dschubba
    of the constellation Scorpius (delta Scorpii). Various flashes
    have been created around the star that have taken on the tints of the
    rainbow, shifting from red (in the lower edge of the star) to blue /
    purple in the upper edge. The same phenomenon happened shortly after
    during the rising of Mars which presented different flashes and colors
    mainly of red and green.
    * Sampieri, Sicily Coordinates: 36.7219, 14.7370

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    * Color and Light in Nature
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    * 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 14 weeks, 3 days, 21 minutes
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  • From Black Panther@21:1/186 to All on Tue Aug 9 12:00:34 2022
    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.


    Ancient Fossil Assemblage Discovered in Utah

    August 09, 2022

    JoeB_3 (7)

    JoeB_1 (18)

    Photographer: Joe Bauman

    Summary Author: Joe Bauman

    While hunting trilobites in 1994, my son, Sky, and I came upon a
    Cambrian site in Utah that at first seemed unpromising. But decades
    later, when I resumed studying rocks picked up there, it became obvious
    that this is one of the world’s most remarkable Lagerstätten
    (extraordinary fossil assemblages) formations, with exceptional
    preservation, including soft tissue of ancient lifeforms. Because of
    the presence of the sponge-like archaeocyathids, I’m able to date
    it to sometime during the Early Cambrian Period, about 540 million
    or 530 million years ago. All of the fossils I found at this site are
    small, the largest just a few centimeters long; most are far tinier, in
    the range of millimeters or less.

    Among the remains are leaflike forms, possible holdovers from the
    Ediacaran Period of the Precambrian; echinoderms, particularly
    carpoids and Gogia, and arthropods. The most astonishing of the
    last are fossils preserved within globules of crystal (probably
    calcite) or sheathed within it (bottom photo). Remains thus preserved
    often show soft material such as legs and internal structures. Note
    that insects preserved in amber are at least 200 million years younger.

    To protect the site from collectors, it’s important to keep the
    location secret from the public. But I’m hopeful that academic
    paleontologists will want to know the location and to borrow specimens,
    with which I’ll gladly comply. Eventually, many of the specimens I
    found will be donated to the Utah Museum of Natural History in Salt
    Lake City. Scientists interested in learning more may contact me
    at josephmbauman@yahoo.com.

    For a fuller description, see my blog at The Early Cambrian: A New
    Utah Lagerstätte (the-nightly-news.com)



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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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  • From Black Panther@21:1/186 to All on Fri Sep 9 12:01:10 2022
    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.


    Twilight Comparison at Curitiba, Brazil, Before and Post Eruption of
    Hunga Tonga

    September 09, 2022

    Ep2016-07-07 e 2022-06-12 - Sol a -11 graus

    Photographer: Fabiano Belisário Diniz
    Summary Author: Fabiano Belisário Diniz

    Shown above is a dramatic comparison between a normal twilight and a
    volcanic twilight as observed from Curitiba, Brazil, on July 7,
    2017 (top) and on June 12, 2022 (bottom). Ash from the Hunga
    Tonga volcano played a major role in enhancing the dusk colors on
    the 2022 photo. Note that both photos were taken when the sun was 11
    degrees below the horizon in Curitiba. Many places in the southern
    hemisphere, and elsewhere, have been experiencing particularly
    colorful twilights since late January, some two weeks after the
    eruption.

    Photo details: Although both photos show the same stage of twilight
    (sun at -11 degrees), the city lights appear fainter in the bottom
    photo because I used a graduated filter with the dark portion facing
    down.


    Curitiba, Brazil Coordinates: -25.4372, -49.2700

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    * 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 27 weeks, 4 days, 21 minutes
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  • From Black Panther@21:1/186 to All on Sun Oct 9 12:01:10 2022
    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.


    Two Views of the Wondrous Andromeda Galaxy

    October 07, 2022

    GregP_Combine_Sky90_Hyperstar_200mm_EPOD_2

    GregP_M31_85subs_3mins_EPOD

    Photographer: Greg Parker

    Summary Authors: Greg Parker; Jim Foster

    The Andromeda Galaxy (M31) is considered the most distant
    object that we can detect with the unaided eye. If you live in the
    Northern Hemisphere and have never seen a galaxy, other than our
    Milky Way, you owe it to yourself to venture into the countryside
    on a clear, moonless autumn evening and look to the northeast. Between
    the stars is the asterism of the Square of Pegasus and the
    constellation of Perseus, a very faint glow will appear in the
    constellation of Andromeda. You may need to use averted vision
    to see it. If you still can’t spot it, grab a pair of binoculars.

    Of course, don’t expect to see anything that resembles the remarkable
    images above, captured from the New Forest Observatory.
    Nevertheless, just being able to discern this distant smudge (some
    2.5 million light years away) is thrilling. The light we see when we
    gaze at M31 began its path to our eyes about the time that North
    America and South America were linked by the Isthmus of Panama and
    around the time our ancestors were starting to stand upright. We can
    see it with the naked eye not only because it’s relatively close by
    (one of the Milky Way's nearest galactic neighbors), but because it’s
    huge -– 220,000 light years across, holding perhaps a trillion stars.

    Photo details:

    Top "zoomed out view" - Canon 200 mm prime lens; ASI 2600MC Pro colour
    CMOS camera.

    Bottom: “zoomed in view” - Hyperstar 4 (on a Celestron C11 telescope)
    image; ASI 2600MC Pro colour CMOS camera.

    New Forest Observatory, U.K. Coordinates: 50.819444, -1.59


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  • From Black Panther@21:1/186 to All on Wed Nov 9 11:01:02 2022
    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.


    Cloud Shadow Projection over Novi Ligure, Italy

    November 09, 2022

    Nuvola e ombra (2)

    Photographer: Valter Luna

    Summary Authors: Valter Luna; Jim Foster

    The photo above showing an eye-catching cloud shadow was captured
    from my home in Novi Ligure, Italy on July 30, 2022. Shadow projections
    such as shown here are formed when a shadow is cast upon a layer of
    thin dust or haze. The scattering angle of sunlight by the
    aerosols within the layer plays a role in observing the projected
    shadows. Typically, you’ll have more success seeing them if you’re
    looking in the vicinity of the Sun – about 10 degrees away or about the
    width of your fist when extended as arm’s length. Also, it seems that
    they can be seen more often in cumulus congestus clouds than in
    other cloud types.

    Photo details: Nikon D100 camera; Sigma 18-250 lens; 50mm; 1/200 second
    exposure; f / 16; ISO 200.


    Novi Ligure, Italy Coordinates: 44.7620, 8.7859


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

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  • From Black Panther@21:1/186 to All on Fri Dec 9 11:01:10 2022
    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.


    Crystal Forms in Petrified Wood

    December 09, 2022

    TomMc_EPODImage2.WolverineLoopPetrifiedForest2022#2 (003)

    TomMc_EPODImage1.PetrifiedWoodWolverineClose2022#1 (003)

    Photographer: Thomas McGuire

    Summary Author: Thomas McGuire


    Grand Staircase National Monument is a spectacularly rich geologic
    area in remote southern Utah. Within this monument, Wolverine
    Petrified Forest, shown above at top, features silicified (petrified)
    tree trunks and sections. The variety of colors is caused by iron
    oxide and other oxide minerals.


    In the bottom photo, the geometric forms at right are dark stained
    quartz crystals that probably grew by groundwater deposition in
    openings called “ vugs.” Quartz is extremely common, but visible
    quartz crystals less so. When an igneous rock cools and
    crystallizes, quartz is the last common mineral to harden, so it
    usually fills in the irregular openings between previously formed
    minerals including feldspar, mica, amphibole and pyroxene. What
    surprised me was the texture on this expose surface. The radial forms
    at the bottom of the photo are new to me, and I have yet to understand
    how they formed. Photos taken in July 2022.



    Grand Staircase National Monument, Utah Coordinates: 37.799633,
    -111.214906


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    * General Dictionary of Geology
    * Mineral and Locality Database
    * Mohs Scale of Mineral Hardness
    * This Dynamic Earth
    * USGS
    * MyShake - University of California, Berkeley
    * USGS Ask a Geologist
    * USGS/NPS Geologic Glossary
    * USGS Volcano Hazards Program

    -
    Earth Science Picture of the Day is a service of the Universities
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    https://epod.usra.edu

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