Photos of Nature | Nature Photography What is The Universe: Across The Universe

Wednesday, February 14, 2018

Across The Universe - Venus and the Triply Ultraviolet Sun

Venus and the Triply Ultraviolet Sun:

Discover the cosmos!
Each day a different image or photograph of our fascinating universe is
featured, along with a brief explanation written by a professional astronomer.

2018 February 4

See Explanation. Clicking on the picture will download the highest resolution version available.

Venus and the Triply Ultraviolet Sun

Image Credit:
NASA/SDO
& the AIA, EVE, and HMI teams;
Digital Composition:
Peter L. Dove

Explanation:
An unusual type of solar eclipse occurred in 2012.

Usually it is the
Earth's Moon that
eclipses the Sun.

That year, most unusually, the planet
Venus took a turn.

Like a solar eclipse by the Moon, the phase of Venus became a continually thinner
crescent as Venus became increasingly
better aligned with the Sun.

Eventually the alignment became perfect and the
phase of Venus dropped to zero.

The dark spot of Venus crossed our parent star.

The situation could technically be labeled a Venusian
annular eclipse with an extraordinarily large
ring of fire.

Pictured here during the occultation, the Sun was imaged in three colors of ultraviolet light by the Earth-orbiting
Solar Dynamics Observatory,
with the dark region toward the right corresponding to a
coronal hole.

Hours later, as Venus continued in its orbit, a
slight crescent phase appeared again.

The next Venusian transit across the Sun will occur in
2117.

Tomorrow's picture: bubble versus cloud

Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell (UMCP)
NASA Official: Phillip Newman
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ASD at
NASA /
GSFC

& Michigan Tech. U.

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NASA Photos Photography

The National Aeronautics and Space Administration (NASA) is the United States government agency responsible for the civilian space program as well as aeronautics and aerospace research. President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA's predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

UFO SIGHTINGS PHOTO PHOTOGRAPHY

The Oxford English Dictionary defines a UFO as "An unidentified flying object; a 'flying saucer'." The first published book to use the word was authored by Donald E. Keyhoe. The acronym "UFO" was coined by Captain Edward J. Ruppelt, who headed Project Blue Book, then the USAF's official investigation of UFOs. He wrote, "Obviously the term 'flying saucer' is misleading when applied to objects of every conceivable shape and performance. For this reason the military prefers the more general, if less colorful, name: unidentified flying objects. UFO (pronounced Yoo-foe) for short." Other phrases that were used officially and that predate the UFO acronym include "flying flapjack", "flying disc", "unexplained flying discs", "unidentifiable object", and "flying saucer". The phrase "flying saucer" had gained widespread attention after the summer of 1947. On June 24, a civilian pilot named Kenneth Arnold reported seeing nine objects flying in formation near Mount Rainier. Arnold timed the sighting and estimated the speed of discs to be over 1,200 mph (1,931 km/h). At the time, he described the objects' shape as being somewhat disc-like or saucer-like, leading to newspaper accounts of "flying saucers" and "flying discs". In popular usage the term UFO came to be used to refer to claims of alien spacecraft. and because of the public and media ridicule associated with the topic, some investigators prefer to use such terms as unidentified aerial phenomenon (or UAP) or anomalous phenomena, as in the title of the National Aviation Reporting Center on Anomalous Phenomena (NARCAP).

UFO PHOTO PHOTOGRAPHY

UFO - Unidentified Flying Object An unidentified flying object, or UFO, in its most general definition, is any apparent anomaly in the sky that is not identifiable as a known object or phenomenon. Culturally, UFOs are associated with claims of visitation by extraterrestrial life or government-related conspiracy theories, and have become popular subjects in fiction. While UFOs are often later identified, sometimes identification may not be possible owing to the usually low quality of evidence related to UFO sightings (generally anecdotal evidence and eyewitness accounts). Stories of fantastical celestial apparitions have been told since antiquity, but the term "UFO" (or "UFOB") was officially created in 1953 by the United States Air Force (USAF) to serve as a catch-all for all such reports. In its initial definition, the USAF stated that a "UFOB" was "any airborne object which by performance, aerodynamic characteristics, or unusual features, does not conform to any presently known aircraft or missile type, or which cannot be positively identified as a familiar object." Accordingly, the term was initially restricted to that fraction of cases which remained unidentified after investigation, as the USAF was interested in potential national security reasons and/or "technical aspects" (see Air Force Regulation 200-2). During the late 1940s and through the 1950s, UFOs were often referred to popularly as "flying saucers" or "flying discs". The term UFO became more widespread during the 1950s, at first in technical literature, but later in popular use. UFOs garnered considerable interest during the Cold War, an era associated with a heightened concern for national security. Various studies have concluded that the phenomenon does not represent a threat to national security nor does it contain anything worthy of scientific pursuit (e.g., 1951 Flying Saucer Working Party, 1953 CIA Robertson Panel, USAF Project Blue Book, Condon Committee).