• ES Picture of the Day 28 2021

    From Dan Richter@1:317/3 to All on Wed Jul 28 11:00:38 2021
    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.


    Contrail Shadow Over Braunfels, Germany

    July 28, 2021

    2021-04-24 15.47.412

    Photographer: Oliver Stiehler

    Summary Author: Oliver Stiehler & Cadan Cummings

    2021-04-24 15.47.43 Sometimes being in the right place at the right
    time produces an unusual photo that reveals unique atmospheric
    phenomena. This photo shows an airplane contrail casting a shadow
    on wispy cirrus clouds in Braunfels, Germany. Contrails are
    formed when water from the airplane exhaust and the atmosphere
    condenses due to extremely cold temperatures and low
    atmospheric pressure. The result is line shaped clouds are produced
    which depending on wind speed and humidity can last for anywhere
    between seconds to several minutes.

    From this unique perspective, the contrail overhead is casting a shadow
    on a lower altitude cloud layer. Note that the shadow appears to be
    also ahead of the jet itself, which is explained by the Sun angle
    being directly overhead in addition to the condensation and ice
    crystals in the contrail scattering the incoming light making the
    shadow’s projection appear larger.

    Photo data: Huawei Mate 20 Pro with all automatic adjustment at 3x zoom
    factor
    * Braunfels, Germany Coordinates: 50.5169, 8.3909

    Related EPODs

    Contrail Shadow Over Braunfels, Germany Lenticular Cloud over
    Turin, Italy Archive - Fire in the Clouds Grim Clouds over the
    Paris Skyline Altocumulus Cloud Deck Above Varese, Italy Wave
    Clouds over Northwestern Washington State
    More...

    Cloud Links

    * Atmospheric Optics
    * The Cloud Appreciation Society
    * Cloud Atlas
    * Color and Light in Nature

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

    https://epod.usra.edu

    --- up 11 weeks, 5 days, 12 hours, 15 minutes
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)
  • From Dan Richter@1:317/3 to All on Sat Aug 28 11:00:24 2021
    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 - Erta Ale, Ethiopia

    August 28, 2021

    6a0105371bb32c970b01b7c768d93c970b
    Every weekend we present a notable item from our archives.
    This EPOD was originally published April 7, 2015.

    Photographer: Joel Santos
    Summary Author: Joel Santos April 2015 Viewer's Choice

    Erta Ale is a continuously active, basaltic shield
    volcano in the Afar Region of northeastern Ethiopia. Its
    caldera is notable for holding one of world's longest-existing
    lava lakes -- first reported in 1906. Volcanoes with lava lakes are
    quite rare. Only six are known worldwide. The nearly full Moon, on
    the rise this early January night, illuminates the low clouds, acting
    to balance the light of the sky with the strong orange light of the
    bursting lava. Photo taken on January 10, 2015.

    Photo details: Fisheye lens; 8-15 mm; 85 sec exposure; f/4; ISO 400.
    * Erta Ale, Ethiopia Coordinates: 13.599722, 40.659722

    Related EPODs

    Archive - Erta Ale, Ethiopia Archive - Ribeira da Janela,
    Portugal Atoms and Molecules Archive - Bonneville Salt Flats
    Panorama Mount Etna – Eruption Plume and Scattered Lapilli
    Willow Falls Near Hudson, Wisconsin
    More...

    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 16 weeks, 1 day, 12 hours, 15 minutes
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)
  • From Dan Richter@1:317/3 to All on Sun Nov 28 11:00:28 2021
    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 - Water Drops and Inverted Images

    November 27, 2021

    6a0105371bb32c970b015438b70cf2970c-750wi

    Every weekend we present a notable item from our archives.

    This EPOD was originally published December 24, 2011.

    Photographer: Bertrand Kulik
    Summary Authors: Bertrand Kulik; Jim Foster
    Within these decorative water drops is the inverted image of
    the flowers in my garden and my house in Paris, France. A liquid drop
    acts as a simple lens, like a camera lens, so the refracted
    image is upside-down when viewed through the drop. Note that these
    drops have more or less spherical shapes because surface tension
    minimizes the surface area of a drop of water or even a falling
    raindrop. Photo taken in early September 2011.

    Photo Details: Canon EOS 7D camera; 100mm macro lens with macro rings.
    * Paris, France Coordinates: 48.856667, 2.350833

    Recent EPODs

    vortex_clouds_around_mount_etna
    a_manycolored_fall_in_blacksmith_fork_canyon
    northern_lights_over_the_norwegian_sea
    hiking_to_eagle_peak_in_yosemite_national_park
    navajo_mountain_and_lake_powell archive_bountiful_autumn
    -
    Earth Science Picture of the Day is a service of the Universities
    Space Research Association.

    https://epod.usra.edu

    --- up 2 weeks, 2 days, 16 hours, 24 minutes
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)
  • From Dan Richter@1:317/3 to All on Tue Dec 28 11:00:26 2021
    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 Cataclysmic Birth of Montana’s Earthquake Lake

    December 28, 2021
    QuakeLk261c_5sep21

    Quakelake210c_5sep21

    Photographer: Ray Boren

    Summary Author: Ray Boren

    In a time when cinematic and fantasy apocalypses abound, it is sobering
    to visit memorials to real-life tragedies, such as the U.S. Forest
    Service’s Earthquake Lake Visitor Center in southern Montana’s
    Custer Gallatin National Forest. The visitor center, shown in the
    left photo, stands amongst a tremendous swath of rocky debris. Below
    the center is the Madison River and the dead-tree-studded
    Earthquake Lake. To the east of the visitor center is U.S. Highway
    287, shown in the right photo, which rounds the 5-mile-long
    (8-kilometer) Earthquake Lake. The lake got its name after forming six
    decades ago as a result of the cataclysmic Hebgen Lake earthquake
    and the subsequent Madison Canyon landslide.

    As described by the visitor center, the powerful earthquake — 7.5
    on the Richter scale — occurred just before midnight on the moonlit
    summer evening of August 17, 1959. About 250 people had gone to bed in
    the canyon in tents, campers and cars at formal and informal campsites,
    as well as others nearby in cabins and lodges. “In the morning,”
    survivor Joann Gartland is quoted as saying, “we looked across from
    where we were, and the mountain had just fallen down.” After a night of
    confusion, terror and resilience, that sunrise revealed the desolation
    and carnage.

    QuakeLk247c_5sep21 The simultaneous tremors from the Red Canyon
    and Hebgen faults sent cascades roaring down the Madison River. Soon
    after, a section of the southern heights dislodged causing the canyon
    and river to be choked with 80 million tons of boulders, rubble and
    shattered trees. Debris formed a natural dam that created
    Earthquake Lake. Unsuspecting people were sadly crushed, trapped or
    lost in the dark, amid churning water, fallen rubble and wrecked cars
    and campers. Many survivors found and helped others with their injuries
    as well as guided them in the night to higher ground to await rescue,
    including to a spot now called Refuge Point.

    Inside the visitor center, poignant displays tell the stories of many
    survivors, of which some were young children at the time. A side road
    and various trails lead to viewpoints, waysides and markers. One such
    path leads to the huge block called Memorial Boulder, shown to the
    right. Far from its original location high on the other side of the
    canyon, it bears a plaque with the names of 28 people killed by the
    Hebgen Lake earthquake and the Madison slide — 19 of whom were
    entombed.
    * Earthquake Lake, Montana Coordinates: 44.831178, -111.422882

    Related EPODs

    The Cataclysmic Birth of Montana’s Earthquake Lake Austrian
    Alps – The Sound of Music Slickrock: A Rock Surface, A Town, and A
    Geological Unit Belt Meteor Crater - Actually A Sinkhole
    Archive - Ubehebe Crater Cumbre Vieja Eruption Column
    More...

    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 3 weeks, 2 days, 20 hours, 43 minutes
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)