• ES Picture of the Day 30 2020

    From Black Panther@21:1/186 to All on Thu Jan 30 14:01:06 2020
    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.


    Star Trails and Moiré Patterns in Night-Sky Photography

    January 30, 2020

    Star Trails On Desert

    Photographer: Nima Asadzadeh
    Summary Author: Nima Asadzadeh

    The star trails shown above were viewed over the Maranjab Desert in
    Iran. You may be able to notice that some of the star trails,
    particularly at the center of the image, form rather unusual
    symmetrical patterns. These patterns result from an optical phenomenon
    that’s called the moiré effect. Whenever we observe repetitive
    shapes, the light rays that reach our eyes are interfered with in such
    a way to form rather symmetrical patterns. This seems to be the case no
    matter the detector, human eyes, CCD cameras, etc. To avoid seeing
    these shapes, better resolution is needed to separate out all the tiny
    sections of the whole image so other paths are available for the light
    rays to reach our eyes without interference. For instance, looking
    through the holes of mesh fencing from up close rather than from a
    dozen feet away.

    In this image, the interval between consecutive shots is about 1 second
    more than the appropriate shutter speed for an 18 mm focal length.
    This extra second causes a gap between each of the shots required to
    make the image and the repetitive trails of the stars, causing the
    moiré patterns to appear. A zoom-viewed image is used to compare
    with the full-size image. Note that the brightest star trail is that of
    the brightest star in the sky, Sirius. Image taken on December 14,
    2019.
    * Maranjab Desert, Iran Coordinates: 34.1832, 51.1332

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    Irene's Milky Way Mirror Moon, Mars and the Moon's Glitter Path
    Large and Small Magellanic Clouds
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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

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

    https://epod.usra.edu

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    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)
  • From Black Panther@21:1/186 to All on Mon Mar 30 13:01:36 2020
    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, Jupiter, the Moon and Mars Alignment and the ISS

    March 30, 2020

    Saturn Jupiter Moon Mars Alignment and ISS Passage 19 February 2020
    Label EPOD

    Photographer: Dario Giannobile
    Summary Authors: Dario Giannobile; Jim Foster

    Just before daybreak on the morning of February 19, 2020, it was
    possible to witness a very fascinating celestial show. Near the end of
    the astronomical night I observed Saturn, Jupiter, Mars and
    the Moon, all rising over this marine coast on the island of Sicily
    (Italy). Note that the ashen, waning moon is accented by a
    corona.

    The International Space Station passed over almost exactly when the
    ambient light was changing. This is why this image shows the
    transition from night to dawn by means of multiple shots, allowing me
    to track the ISS across the sky. This crossing lasted 4 minutes, during
    which time the light changed considerably.

    Early tomorrow morning, before dawn, Mars passes just south (0.9
    degrees) of Saturn, and Jupiter is just 6.3 degrees west of this bright
    duo. If youΓÇÖre up early, make sure to take a look.
    * Syracuse, Italy Coordinates: 37.0755, 15.2866

    Related EPODs

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    Betelgeuse at its Minimum Brightness Encore - Geminid Meteors
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    Quadrantid Meteor Shower
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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

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

    https://epod.usra.edu

    --- up 9 weeks, 5 days, 14 hours, 5 minutes
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)
  • From Black Panther@21:1/186 to All on Sat May 30 15:01:52 2020
    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 - Summer Lightning in Florida

    May 30, 2020

    Lightning.2014-06-20_11.36pmEDT.GNV

    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: Howard L. Cohen
    Summary Author: Howard L. Cohen

    Shown above is a photo of an amazing lightning display from active
    late evening thunderstorms in north-central Florida. It was taken
    at 11:36 on the night of June 20, 2014. Extensive cloud-to-cloud
    lightning, including numerous flashes of sheet lightning, brightly
    lit the skies around the city of Gainesville.
    Stargazers already know that summer weather in Florida isn't very
    friendly to their avocation. Moist warm air rising over the Florida
    peninsula and intense daytime heating often result in thunderstorms
    with abundant lightning, especially during afternoons and evenings. As
    is typically the case with Florida's summer storms, the fireworks
    gradually diminish and by sunrise, clear blue skies prevail.

    Photo Details: Canon DSLR EOS 5D Mark II camera; Canon 20-35 mm lens;
    f/3.5-4.5 USM at 28 mm; Equiv. ISO 200; 30 seconds exposure at f/11;
    image slightly cropped from original frame. Processed in Corel Paint
    Shop Pro X5.
    * Gainesville, Florida Coordinates: 29.6520, -82.3250

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    Atmospheric Effects Links

    * Atmospheric Optics
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    * The Colors of Twillight and Sunset
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    * Image Gallery: Atmospheric Effects
    * What is a Rainbow?

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    Severe Weather Links

    * World Severe Weather Information Center
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    * A Lightning Primer
    * More About Thunderstorms
    * Staying Safe Outdoors in Severe Weather
    * NOAA Storm Prediction Center
    * Patterns of Lightning Activity
    * US National Weather Service

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

    https://epod.usra.edu

    --- up 18 weeks, 3 days, 16 hours, 5 minutes
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)
  • From Black Panther@21:1/186 to All on Tue Jun 30 15:02:08 2020
    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.


    Lava Tube on La Palma

    June 30, 2020

    T3 Cueva Palomas

    Photographer: Antonio Gonzalez
    Summary Author: Antonio Gonzalez

    This panoramic composition shows an immersive 360-degree image of a
    volcanic cave, or lava tube, on La Palma island in the
    Canary Islands of Spain. The Canaries, like the Hawaii islands,
    were born as a result of volcanic activity.
    In 1949, the San Juan volcano expelled lava that passed through
    the area where the cave is now. The upper part of the lava flow was in
    contact with the air and cooled very quickly; while in the lower part
    of the flow, where the panorama was made, lava continued to circulate
    well after the upper part cooled. As the lava level came down, it
    eventually formed this cave – a hollowed out river of hardened lava
    approximately 1800 ft (549 m) in length. It’s open to the public and
    very easy to walk through. Note that the formation of lava caves is
    very different than caves that form in a karst topography

    This panoramic picture was made with a group of 3 immersive 360-degree
    photographs on June 27, 2015. Click here to see similar photos.
    Thanks to the Innovation área of Cabildo La Palma and to Eduardo Diaz y
    Paco Govantes for their help.
    * La Palma, Spain Coordinates: 28.601276, -17.890769

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    Geology Links

    * Earthquakes
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    * General Dictionary of Geology
    * Mineral and Locality Database
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    * This Dynamic Earth
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    -
    Earth Science Picture of the Day is a service of the Universities
    Space Research Association.

    https://epod.usra.edu

    --- up 22 weeks, 6 days, 16 hours, 5 minutes
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)
  • From Black Panther@21:1/186 to All on Thu Jul 30 15:00:32 2020
    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.


    Cirrus Rows

    July 30, 2020

    D4D7C491-1A91-4312-9860-93DD77F3F022

    Photographer: Sally Budack
    Summary Authors: Sally Budack; Jim Foster
    Driving near my home in Tacoma, Washington, several weeks ago I noticed
    a curious cloud formation with oddly regular stripes. I pulled over to
    take the picture shown above. These clouds dissipated quite quickly.
    They appear to be a type of cirrus cloud ( cirrus fibratus) that
    tends to become oriented in the direction of the upper air flow,
    resulting in parallel rows -- like window blinds to the upper
    atmosphere. Photo taken on June 11, 2020.

    Photo Details: Camera - Apple iPhone 6s; Exposure Time - 0.0001s
    (1/8547); Aperture - ƒ/2.2; ISO equivalent - 25; Focal Length (35mm) -
    146.
    * Tacoma, Washington Coordinates: 47.2529, -122.4443

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    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 2 weeks, 15 hours, 25 minutes
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