• ES Picture of the Day 25 2020

    From Black Panther@21:1/186 to All on Saturday, January 25, 2020 09:01:02
    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 - Snow Eyes

    January 25, 2020

    Snow eyes 1
    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 Adam
    Summary Author: John Adam

    Snow eyes inset April 2014 Viewer's Choice Early in March 2014,
    I took this series of photographs on the way to my office at Old
    Dominion University in Norfolk, Virginia. There had been a snowfall
    of an inch or two (2.5-5.0 cm) the previous day and the temperature was
    a couple of degrees above freezing (32 F or 0 C). I was intrigued by
    this pattern of eyes in the snow over two very different length
    scales. The smaller one, the gap between adjacent eyes, was 5-6 in
    (12-15 cm). There was an electrical power line above from which melting
    ice could drip onto the road, but it was taut and straight; whereas the
    position of the eyespots followed the curve of the snow-covered grassy
    median to a great extent. Furthermore, it's unlikely that the pattern
    from melting snow would have been so regularly distributed. Paw prints
    of a one-legged dog, perhaps. Possibly, it was a woman wearing boots
    with narrow heels; the wet snow might have been thin enough under the
    sole of the boot to melt more rapidly than around the heel. The
    cone-like residue from the heel-print is all that remained.
    Given the small distance between them, the stride would have been only
    about a foot long (30 cm); though small mincing steps might have been a
    result of the person worrying about slipping on ice. But, paw or
    footprints of some kind would surely be alternatively offset more than
    they are here, so that doesn’t seem to be a completely realistic
    explanation. I'm pretty sure it wasn't a clown juggling power tools
    while wearing stiletto heels. Maybe readers can supply a more
    convincing explanation. Thanks to Doug Stith, Steve Arcone and Jim
    Foster for an interesting discussion.

    Photo Details: Top - Camera: Olympus SP570UZ; Focal Length: 4.6mm;
    Aperture: f/5.6; Exposure Time: 0.0040 s (1/250); ISO equiv: 64. First
    inset - same except: Exposure Time: 0.0031 s (1/320). Second inset -
    same except: Focal Length: 17.1mm; Aperture: f/5.0; Exposure Time:
    0.0050 s (1/200).
    * Old Dominion University, Virginia Coordinates: 36.8865,
    -76.3052

    Related EPODs

    Encore - Snow Eyes Icy Drops Snow Blankets Joshua Tree
    National Park Encore - Lake Michigan Ice Cave Hexagonal Plate
    Snow Crystal Northern Hemisphere Seasonal Snow Cover Map (December
    20, 2019)
    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 3 days, 15 hours, 4 minutes
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  • From Black Panther@21:1/186 to All on Tuesday, February 25, 2020 09:01:24
    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.


    Bosco di Santo Pietro Natural Reserve

    February 25, 2020

    DSCN6242 (1)

    DSCN6171

    Photographer: Barbara Pindo
    Summary Author: Barbara Pindo

    I recently had the pleasure to visit the natural reserve of Bosco
    di Santo Pietro (Sicily, Italy); a protected natural area extending
    along a large sandy plateau that’s furrowed by valleys. Though over 300
    plant species are found here, there are 3 main habitats, the
    cork oak, the holm oak and the garrigue (a mixed shrub and
    grass habitat). Unfortunately, the colossal cork oaks of the past have
    largely disappeared today. It’s believed that no more than 50 of these
    huge cork trees remain, one of which is shown above. It’s a true
    wonder! I felt like I was in a Tolkien novel and that Gandalf
    could reach me at any moment.

    The bottom photo shows some of the rich undergrowth of this reserve --
    cyclamen are in the foreground. Photos taken on January 19, 2020.

    Photo Details: Top - Camera NIKON COOLPIX L110; Exposure Time 0.029s
    (1/35); Aperture ƒ/3.5; ISO equivalent 80; Focal Length (35mm) 28.
    Bottom same except - Exposure Time 0.031s (1/32); ISO equivalent 400.
    * Bosco di Santo Pietro, Italy Coordinates: 37.1312, 14.5306

    Related EPODs

    Bosco di Santo Pietro Natural Reserve Nature Nurturing Nature:
    Stump Flowerpots Chrysanthemums Ancient Tree and Pareidolia
    Archive - Long-lived Olive Trees Redbud Firewood
    More...

    Plant Links

    * Discover Life
    * Tree Encyclopedia
    * What are Phytoplankton?
    * Encyclopedia of Life - What is a Plant?
    * USDA Plants Database
    * University of Texas Native Plant Database
    * Plants in Motion
    * What Tree is It?

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

    https://epod.usra.edu

    --- up 4 weeks, 6 days, 15 hours, 5 minutes
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)
  • From Black Panther@21:1/186 to All on Wednesday, March 25, 2020 09:02:28
    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.


    Betelgeuse at its Minimum Brightness

    March 25, 2020

    Betelgeuse_200215_Orion_widefield (003)

    Photographer: Martin Dietzel
    Summary Authors: Martin Dietzel; Jim Foster

    Featured above is the red supergiant, Betelgeuse, in the
    constellation of Orion. Betelgeuse has been conspicuously
    fading the past several months, losing approximately 1
    magnitude of brightness from 0.7 in September 2019 to 1.8 in early
    February. According to several recent studies, the minimum was reached
    around February 15, 2020, which is when this picture was taken. Note
    that atmospheric conditions were not perfect, as fog was beginning to
    form. The origin of this fainting process isn’t fully understood, but
    Betelgeuse has been observed to fade and brighten for centuries.
    However, it now appears to be brightening again.

    It’s amazing to look up at the heavens and see such a noticeable
    difference, over a period of weeks, of one of the brightest stars in
    the night sky. Look for Betelgeuse and Orion in the southwestern sky
    after nightfall. Photo captured near Heidenheim, Germany.

    Photo Details: Canon EOS camera; 40 mm f/4 lens; taken with a tripod
    only, no tracking mount was used.
    * Heidenheim, Germany Coordinates: 48.6894, 10.1611

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    Quadrantid Meteor Shower Encore - Lake Irene's Milky Way Mirror
    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 9 weeks, 14 hours, 6 minutes
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)
  • From Black Panther@21:1/186 to All on Thursday, June 25, 2020 11:00:32
    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.


    Young Lava and Old Olivine

    June 25, 2020

    MilaZ_e1 (002)

    6a0105371bb32c970b0263ec21bb2e200c

    Photographer: Mila Zinkova
    Summary Author: Mila Zinkova

    Have you ever held a rock that was created an hour ago? I did (top
    photo) in July of 2018. This rock was created when debris from a
    steam explosion hit a boat touring newly-formed lava on the
    Big Island of Hawaii. The explosion produced hot rocks ( lava
    bombs) that landed on the boat and actually injured several tourists.
    Because my hotel was nearby, I noticed that the boat came back 2-hours
    before it should have, so I went to the pier to see why. Click here
    to see what I saw. Two days before, I took the same tour with
    the same company.

    While the rock from the first picture is the newest I've ever held, the
    rock pictured in the bottom photo is one of the oldest. It is a
    meteorite, a pallasite to be exact. If you look closely you’ll
    notice it has some greenish-yellowish crystals. These are olivine
    crystals. Pallasites are stony-iron meteorites that contain olivine
    and iron. They’re believed to come from the core of large
    asteroids. Olivine is usually green, but it often doesn’t last long
    in meteorites. It turns out that Earth’s atmosphere isn’t a healthy
    environment for pallasites since they’re prone to a type of
    chemical weathering referred to as Lawrencite disease, which
    causes olivine to be removed.

    The lava rock in the first photo has olivine too -- olivine often
    occurs in lava rocks. In fact, a green, sand beach on the Big
    Island of Hawaii formed when olivine-rich lava eroded as it reached the
    ocean.

    Photo Details: Top - Camera: Apple iPhone 8; Software: Adobe Photoshop
    CS3 Windows; Exposure Time: 0.0039s (1/257); Aperture: ƒ/1.8; ISO
    equivalent: 20; Focal Length (35mm): 139. Bottom - Camera: Apple iPhone
    6; Software: Adobe Photoshop CS3 Windows; Exposure Time: 0.0016s
    (1/608); Aperture: ƒ/2.2; ISO equivalent: 32; Focal Length (35mm): 76.
    * Big Island of Hawaii Coordinates: 19.566667, -155.5

    Related EPODs

    Young Lava and Old Olivine A Crack in the Moon? Mount Etna
    and Pillow Lava of Aci Castello Archive - Blended Image of Rock
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    - Soufriere Hills Volcano
    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 22 weeks, 1 day, 16 hours, 4 minutes
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)
  • From Black Panther@21:1/186 to All on Saturday, July 25, 2020 11:01:24
    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 - Holuhraun Fissure Eruption

    July 25, 2020

    MoreHolur

    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: William Moreland
    Summary Authors: William Moreland; Stu Witmer

    September 2012 Viewer's Choice Iceland is a creation of
    plate tectonics. The North American and Eurasian plates are
    spreading apart here at the rate of about 1 in (2.5 cm) each year. The
    island abounds with visual evidence of this movement. Most
    recently, a new fissure has erupted in the Holuhraun lava field
    just north of Dyngjujökull, part of the larger Vatnajökull (jökull
    is Icelandic for glacier). The photo above shows the eastern lava field
    of the Holuhraun fissure eruption as the lava meets the Jökulsá á
    Fjöllum, Iceland’s second-longest river. Jökulsá á Fjöllum carries
    meltwater from glaciers near its source to the sea more than
    125 mi (200 km) distant. At the time the photo was taken the lava
    was flowing at a rate of about 328 ft (100 m) per hour and covered 7 sq
    mi (19 sq km) making it the largest such flow Iceland has seen
    since 1875. Photo taken September 8, 2014.
    Photo Details: Camera: HTC One (M8) using the Pan 360 function; Focal
    Length: 3.82 mm; Aperture: f/2.0; Exposure Time: 0.100 s (1/10); ISO
    equiv: 1600.
    * Holuhraun lava field, Iceland Coordinates: 64.93168 -16.56759

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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 1 week, 2 days, 15 hours, 25 minutes
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  • From Black Panther@21:1/186 to All on Tuesday, August 25, 2020 11:00:32
    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.


    Color in Opals

    August 25, 2020

    Mila_opal (003)

    Photographer: Mila Zinkova
    Summary Author: Mila Zinkova

    The most valuable opals, referred to as precious opals, display
    play of color, patches of spectral colors that occur when this
    gemstone is tilted. Both frames of the image above show the same
    Ethiopian opal from Mezezo, and both frames also depict the
    same part of the opal. The dark patches in the left frame became bright
    green/blue when I found the proper angle to display the color. These
    patches are called digits. Making them exhibit colors is simply a
    matter of working to find the right angle. In some opals, digits create
    an elaborate color network, as it is seen in the second opal featured
    in this video. However, only rarely will color appear in multiple
    digits from different clusters at the same time.
    * Mezezo, Ethiopia Coordinates: 9.9338, 39.7315

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