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30/11/2021

ASTRONOMY - The Extraordinary Spiral in LL Pegasi

 2021 November 29

The featured image shows an unusual spiral structure
in the binary star system LL Pegasi as captured by the 
Hubble Space Telescope.
Please see the explanation for more detailed information.

The Extraordinary Spiral in LL Pegasi
Image Credit: NASAESAHubbleHLAProcessing & Copyright: Jonathan Lodge

Explanation: What created the strange spiral structure on the upper left? No one is sure, although it is likely related to a star in a binary star system entering the planetary nebula phase, when its outer atmosphere is ejected. The huge spiral spans about a third of a light year across and, winding four or five complete turns, has a regularity that is without precedent. Given the expansion rate of the spiral gas, a new layer must appear about every 800 years, a close match to the time it takes for the two stars to orbit each other. The star system that created it is most commonly known as LL Pegasi, but also AFGL 3068 and IRAS 23166+1655. The featured image was taken in near-infrared light by the Hubble Space Telescope. Why the spiral glows is itself a mystery, with a leading hypothesis being illumination by light reflected from nearby stars.

29/11/2021

ASTRONOMY - A High Cliff on Comet Churyumov-Gerasimenko

 2021 November 28

The featured image shows a kilometer-high cliff
that occurs on Comet Churyumov-Gerasimenko as imaged by
ESA's Rosetta spacecraft in 2014.
Please see the explanation for more detailed information.

A High Cliff on Comet Churyumov-Gerasimenko
Image Credit & LicenceESARosetta spacecraft, NAVCAM; Additional Processing: Stuart Atkinson

Explanation: This high cliff occurs not on a planet, not on a moon, but on a comet. It was discovered to be part of the dark nucleus of Comet Churyumov-Gerasimenko (CG) by Rosetta, a robotic spacecraft launched by ESA that rendezvoused with the Sun-orbiting comet in 2014. The ragged cliff, as featured here, was imaged by Rosetta in 2014. Although towering about one kilometer high, the low surface gravity of Comet CG would likely make it an accessible climb -- and even a jump from the cliff survivable. At the foot of the cliff is relatively smooth terrain dotted with boulders as large as 20 meters across. Data from Rosetta indicates that the ice in Comet CG has a significantly different deuterium fraction -- and hence likely a different origin -- than the water in Earth's oceans. Rosetta ended its mission with a controlled impact onto Comet CG in 2016. Comet CG has just completed another close approach to Earth and remains visible through a small telescope.

27/11/2021

ASTRONOMY - Messier 101

 2021 November 27

See Explanation.  Clicking on the picture will download
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Messier 101
Image Credit: NASAESACFHTNOAO;
Acknowledgement - K.Kuntz (GSFC), F.Bresolin (U.Hawaii), J.Trauger (JPL), J.Mould (NOAO), Y.-H.Chu (U. Illinois)

Explanation: Big, beautiful spiral galaxy M101 is one of the last entries in Charles Messier's famous catalog, but definitely not one of the least. About 170,000 light-years across, this galaxy is enormous, almost twice the size of our own Milky Way. M101 was also one of the original spiral nebulae observed by Lord Rosse's large 19th century telescope, the Leviathan of Parsontown. Assembled from 51 exposures recorded by the Hubble Space Telescope in the 20th and 21st centuries, with additional data from ground based telescopes, this mosaic spans about 40,000 light-years across the central region of M101 in one of the highest definition spiral galaxy portraits ever released from Hubble. The sharp image shows stunning features of the galaxy's face-on disk of stars and dust along with background galaxies, some visible right through M101 itself. Also known as the Pinwheel Galaxy, M101 lies within the boundaries of the northern constellation Ursa Major, about 25 million light-years away.

26/11/2021

MUSIC - J. S. Bach - "Air" Orchestral Suite N° 3 in D Major

"Orchestral Suite N° 3 in D Major"

ASTRONOMY - Great Refractor and Lunar Eclipse

 2021 November 26

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Great Refractor and Lunar Eclipse
Image Credit & Copyright: Laurie Hatch

Explanation: Rain clouds passed and the dome of the Lick Observatory's 36 inch Great Refractor opened on November 19. The historic telescope was pointed toward a partially eclipsed Moon. Illuminated by dim red lighting to preserve an astronomer's night vision, telescope controls, coordinate dials, and the refractor's 57 foot long barrel were captured in this high dynamic range image. Visible beyond the foreshortened barrel and dome slit, growing brighter after its almost total eclipse phase, the lunar disk created a colorful halo through lingering clouds. From the open dome, the view of the clearing sky above includes the Pleiades star cluster about 5 degrees from Moon and Earth's shadow.

25/11/2021

ASTRONOMY - At the Shadow's Edge

 2021 November 25

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At the Shadow's Edge
Image Credit & Copyright: Jean-Francois Gout

Explanation: Shaped like a cone tapering into space, the Earth's dark central shadow or umbra has a circular cross-section. It's wider than the Moon at the distance of the Moon's orbit though. But during the lunar eclipse of November 18/19, part of the Moon remained just outside the umbral shadow. The successive pictures in this composite of 5 images from that almost total lunar eclipse were taken over a period of about 1.5 hours. The series is aligned to trace part of the cross-section's circular arc, with the central image at maximum eclipse. It shows a bright, thin sliver of the lunar disk still beyond the shadow's curved edge. Of course, even within the shadow the Moon's surface is not completely dark, reflecting the reddish hues of filtered sunlight scattered into the shadow by Earth's atmosphere.

24/11/2021

ASTRONOMY - Pleiades: The Seven Sisters Star Cluster

 2021 November 24

The featured image shows a deep image of the 
Pleiades open star cluster taken from Florida in the USA.
Please see the explanation for more detailed information.

Pleiades: The Seven Sisters Star Cluster
Image Credit & Copyright: Damien Cannane

Explanation: Have you ever seen the Pleiades star cluster? Even if you have, you probably have never seen it as large and clear as this. Perhaps the most famous star cluster on the sky, the bright stars of the Pleiades can be seen without binoculars from even the depths of a light-polluted city. With a long exposure from a dark location, though, the dust cloud surrounding the Pleiades star cluster becomes very evident. The featured exposure, taken from Florida, USA, covers a sky area several times the size of the full moon. Also known as the Seven Sisters and M45the Pleiades lies about 400 light years away toward the constellation of the Bull (Taurus). A common legend with a modern twist is that one of the brighter stars faded since the cluster was named, leaving only six of the sister stars visible to the unaided eye. The actual number of Pleiades stars visible, however, may be more or less than seven, depending on the darkness of the surrounding sky and the clarity of the observer's eyesight.

23/11/2021

ASTRONOMY - The Sun in X-rays from NuSTAR

 2021 November 23

The featured image shows the Sun in X-ray light as
shown by NASA's NuSTAR satellite -- superimposed on an image
in ultraviolet light taken by NASA's Solar Dynamic Observatory.
Please see the explanation for more detailed information.

The Sun in X-rays from NuSTAR
Image Credit: NASANuSTARSDO

Explanation: Why are the regions above sunspots so hot? Sunspots themselves are a bit cooler than the surrounding solar surface because the magnetic fields that create them reduce convective heating. It is therefore unusual that regions overhead -- even much higher up in the Sun's corona -- can be hundreds of times hotter. To help find the cause, NASA directed the Earth-orbiting Nuclear Spectroscopic Telescope Array (NuSTAR) satellite to point its very sensitive X-ray telescope at the Sun. Featured here is the Sun in ultraviolet light, shown in a red hue as taken by the orbiting Solar Dynamics Observatory (SDO). Superimposed in false-colored green and blue is emission above sunspots detected by NuSTAR in different bands of high-energy X-rays, highlighting regions of extremely high temperature. Clues about the Sun's atmospheric heating mechanisms come from NuSTAR images like this and shed light on solar nanoflares and microflares as brief bursts of energy that may drive the unusual heating.

22/11/2021

ASTRONOMY - Lunar Eclipse over a Skyscraper

 2021 November 22

The featured image shows the Moon in partial eclipse over
the Gran Torre Santiago building in Chile. 
Please see the explanation for more detailed information.

Lunar Eclipse over a Skyscraper
Image Credit & Copyright: Yuri Beletsky (Carnegie Las Campanas ObservatoryTWAN)

Explanation: Why is the Moon on top of this building? Planning. It took the astrophotographer careful planning -- including figuring out exactly where to place the camera and exactly when to take the shot -- to create this striking superposition. The single image featured was taken in the early morning hours of November 19, near the peak of the partial lunar eclipse that was occurring as the Moon passed through the Earth's shadow. At this time, almost the entire Moon -- 99.1 percent of its area -- was in the darkest part of the Earth's shadow. The building is the Gran Torre Santiago building in Chile, the tallest building in South America. Although the entire eclipse lasted an impressive six hours, this image had to be taken within just a few seconds to get the alignment right -- the Earth's rotation soon moved the building out of alignment. The next Earth-Moon eclipse will be a total eclipse of the Sun that will occur on December 4 -- but only be visible from the bottom of our world.

CATASTROPHES MARITIMES - Titanic foi filmado pela primeira vez em 4K, veja como ele está hoje


O explorador que tirou as fotos de alta qualidade foi Victor Vescovo, já a empresa responsável foi a Triton Submarines.

O material obtido deverá ser utilizado na produção de um documentário da Atlantic Productions, que ainda não conta com data de lançamento.


De acordo com a empresa, as imagens do navio devem ajudar não só a avaliar a condição atual do Titanic, como também projetar seu futuro.

Além disso, segundo a nota divulgada pela Triton Submarines, as imagens devem possibilitar a visualização do naufrágio com a realidade aumentada (AR) e a tecnologia de realidade virtual (VR).

engenhariahoje

21/11/2021

ASTRONOMY - Introducing Comet Leonard

 2021 November 21

The featured image shows an image of Comet Leonard
complete with a green coma and a dust tail.
Please see the explanation for more detailed information.

Introducing Comet Leonard
Image Credit & Copyright: Dan Bartlett

Explanation: Here comes Comet Leonard. Comet C/2021 A1 (Leonard) was discovered as a faint smudge in January 2021 when it was out past Mars -- but its orbit will take the giant shedding ice-ball into the inner Solar System, passing near both Earth and Venus in December before it swoops around the Sun in early January 2022. Although comets are notoriously hard to predict, some estimations have Comet Leonard brightening to become visible to the unaided eye in December. Comet Leonard was captured just over a week ago already sporting a green-tinged coma and an extended dust tail. The featured picture was composed from 62 images taken through a moderate-sized telescope -- one set of exposures tracking the comet, while another set tracking the background stars. The exposures were taken from the dark skies above the Eastern Sierras (Mountains), near June Lake in CaliforniaUSA. Soon after passing near the Earth in mid-December, the comet will shift from northern to southern skies.

20/11/2021

ASTRONOMY - An Almost Total Lunar Eclipse

 2021 November 20

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

An Almost Total Lunar Eclipse
Image Credit & Copyright: Robert Fedez

Explanation: Predawn hours of November 19 found the Moon in partly cloudy skies over Cancun, Mexico. Captured in this telephoto snapshot, the lunar disk is not quite entirely immersed in Earth's dark umbral shadow during a long partial lunar eclipse. The partial eclipse was deep though, deep enough to show the dimmed but reddened light in Earth's shadow. That's a sight often anticipated by fans of total lunar eclipses. Wandering through the constellation Taurus, the eclipsed Moon's dimmer light also made it easier to spot the Pleiades star cluster. The stars of the Seven Sisters share this frame at the upper right, with the almost totally eclipsed Moon.

19/11/2021

ASTRONOMY - NGC 281: Starless with Stars

 2021 November 19

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NGC 281: Starless with Stars
Image Credit & Copyright: Wido Oerlemans - X-ray: ChandraInfrared: Spitzer

Explanation: In visible light the stars have been removed from this narrow-band image of NGC 281, a star forming region some 10,000 light-years away toward the constellation Cassiopeia. Stars were digitally added back to the resulting starless image though. But instead of using visible light image data, the stars were added with X-ray data (in purple) from the Chandra X-ray Observatory and infrared data (in red) from the Spitzer Space Telescope. The merged multiwavelength view reveals a multitude of stars in the region's embedded star cluster IC 1590. The young stars are normally hidden in visible light images by the natal cloud's gas and obscuring dust. Also known to backyard astro-imagers as the Pacman Nebula for its overall appearance in visible light, NGC 281 is about 80 light-years across.

18/11/2021

ASTRONOMY - Full Moonlight

 2021 November 18

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

Full Moonlight
Image Credit & Copyright: Zhengjie Wu and Jeff Dai (TWAN)

Explanation: A photographer in silhouette stands in bright moonlight as the Full Moon rises in this well-planned telephoto image. Of course, the Full Moon is normally the brightest lunar phase. But on November 18/19, the Full Moon's light will be dimmed during a deep partial lunar eclipse seen across much of planet Earth. At maximum eclipse only a few percent of the lunar disk's diameter should remain outside the Earth's dark umbral shadow when the Moon slides close to the shadow's southern edge. Near apogee, the farthest point in its orbit, the Moon's motion will be slow. That should make this second lunar eclipse of 2021 an exceptionally long partial lunar eclipse. For most of North America the eclipse partial phases will be visible in predawn hours. Since eclipses tend to come in pairs, this lunar eclipse will be followed by a solar eclipse in two weeks on December 4.

17/11/2021

ASTRONOMY - NGC 3314: When Galaxies Overlap

 2021 November 17

The Hubble image shows the two spiral galaxies 
directly overlapping in the system designated NGC 3314.
Please see the explanation for more detailed information.

NGC 3314: When Galaxies Overlap
Image Credit: NASAESA, Hubble; Processing & Copyright: William Ostling (The Astronomy Enthusiast)

Explanation: Why doesn't the nearby galaxy create a gravitational lensing effect on the background galaxy? It does, but since both galaxies are so nearby, the angular shift is much smaller than the angular sizes of the galaxies themselves. The featured Hubble image of NGC 3314 shows two large spiral galaxies which happen to line up exactly. The foreground spiral NGC 3314a appears nearly face-on with its pinwheel shape defined by young bright star clusters. Against the glow of the background galaxy NGC 3314b, though, dark swirling lanes of interstellar dust can also be seen tracing the nearer spiral's structure. Both galaxies appear on the edge of the Hydra Cluster of Galaxies, a cluster that is about 200 million light years away. Gravitational lens distortions are much easier to see when the lensing galaxy is smaller and further away. Then, the background galaxy may even be distorted into a ring around the nearer. Fast gravitational lens flashes due to stars in the foreground galaxy momentarily magnifying the light from stars in the background galaxy might one day be visible in future observing campaigns with high-resolution telescopes.

15/11/2021

ASTRONOMY - Light Pillar over Volcanic Etna

 2021 November 15

The illustration shows a red light-pillar at night over
Mt.Etna, an erupting volcano in Italy. 
Please see the explanation for more detailed information.

Light Pillar over Volcanic Etna
Image Credit & Copyright: Giancarlo Tinè

Explanation: What happening above that volcano? Something very unusual -- a volcanic light pillar. More typically, light pillars are caused by sunlight and so appear as a bright column that extends upward above a rising or setting Sun. Alternatively, other light pillars -- some quite colorful -- have been recorded above street and house lights. This light pillar, though, was illuminated by the red light emitted by the glowing magma of an erupting volcano. The volcano is Italy's Mount Etna, and the featured image was captured with a single shot a few hours after sunset in mid-June. Freezing temperatures above the volcano's ash cloud created ice-crystals either in cirrus clouds high above the volcano -- or in condensed water vapor expelled by Mount Etna. These ice crystals -- mostly flat toward the ground but fluttering -- then reflected away light from the volcano's caldera.

14/11/2021

ASTRONOMY - Moon and Planets at Twilight

 2019 November 28

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Moon and Planets at Twilight
Image Credit & CopyrightPetr Horálek

Explanation: This week's ongoing conjunction of Venus and Jupiter may have whetted your appetite for skygazing. Tonight is the main course though. On November 28, a young crescent Moon will join them posing next to the two bright planets above the western horizon at twilight. Much like tonight's visual feast, this night skyscape shows a young lunar crescent and brilliant Venus in the western evening twilight on October 29. The celestial beacons are setting over distant mountains and the Minya monastery, Ganzi Tibetan Autonomous Prefecture, Sichuan, China, planet Earth. Then Mercury, not Jupiter, was a celestial companion to Venus and the Moon. The fleeting innermost planet is just visible here in the bright twilight, below and left of Venus and near the center of the frame. Tomorrow, November 29, the crescent Moon will also help you spot planet Saturn for dessert.

13/11/2021

ASTRONOMY - Rosetta's Comet in Gemini

 2021 November 13

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Rosetta's Comet in Gemini
Image Credit & Copyright: Rolando Ligustri (CARA ProjectCAST)

Explanation: Returning along its 6.4 year orbit, periodic comet Churyumov-Gerasimenko (67P) is caught in this telescopic frame from November 7. Sweeping past background stars in the constellation Gemini the comet's dusty tail stretches toward the upper right to Upsilon Geminorum. Also known as Pollux, Beta Geminorum, Gemini's brightest star, shines just off the upper left edge of the field-of-view. Churyumov-Gerasimenko reached its 2021 perihelion or closest approach to the Sun on November 2. At perigee, its closest approach to planet Earth on November 12, this comet was about 0.42 astronomical units away, though it remains too faint to be seen by eye alone. The well-studied comet was explored by robots from planet Earth during its last trip through the inner solar system. It's now famous as the final resting place for the historic Rosetta spacecraft and Philae lander.

12/11/2021

ASTRONOMY - Night of the Perseids

2021 September 28

Night of the Perseids
Video Credit & Copyright: Vikas Chander & Dorje Angchuk; Music: Tea Time via PremiumBeat

Explanation: Have you ever experienced a meteor shower? To help capture the wonder, a video was taken during the peak of the recent Perseid meteor shower above the Indian Astronomical Observatory in HanleIndia, high up in the Himalayan mountains. Night descends as the video begins, with the central plane of our Milky Way Galaxy approaching from the left and Earth-orbiting satellites zipping by overhead. During the night, the flash of meteors that usually takes less than a second is artificially extended. The green glow of most meteors is typically caused by vaporizing nickel. As the video continues, Orion rises and meteors flare above the 2-meter Himalayan Chandra Telescope and the seven barrels of the High Energy Gamma Ray Telescope (Hagar). The 2 minute 30 second movie ends with the Sun rising, preceded by a false dawn of zodiacal light

11/11/2021

ASTRONOMY - Video of a Green Flash

2021 November 10

Video of a Green Flash
Video Credit & Copyright: Paolo Lazzarotti

Explanation: Many think it is just a myth. Others think it is true but its cause isn't known. Adventurers pride themselves on having seen it. It's a green flash from the Sun. The truth is the green flash does exist and its cause is well understood. Just as the setting Sun disappears completely from view, a last glimmer appears startlingly green. The effect is typically visible only from locations with a low, distant horizon, and lasts just a few seconds. A green flash is also visible for a rising Sun, but takes better timing to spot. A dramatic green flash was caught on video last month as the Sun set beyond the Ligurian Sea from TuscanyItaly. The second sequence in the featured video shows the green flash in real time, while the first is sped up and the last is in slow motion. The Sun itself does not turn partly green -- the effect is caused by layers of the Earth's atmosphere acting like a prism

ASTRONOMY - NGC 1333: Stellar Nursery in Perseus

 2021 November 11

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NGC 1333: Stellar Nursery in Perseus
Image Credit & Copyright: Michael Sherick

Explanation: NGC 1333 is seen in visible light as a reflection nebula, dominated by bluish hues characteristic of starlight reflected by interstellar dust. A mere 1,000 light-years distant toward the heroic constellation Perseus, it lies at the edge of a large, star-forming molecular cloud. This telescopic close-up spans about two full moons on the sky or just over 15 light-years at the estimated distance of NGC 1333. It shows details of the dusty region along with telltale hints of contrasty red emission from Herbig-Haro objects, jets and shocked glowing gas emanating from recently formed stars. In fact, NGC 1333 contains hundreds of stars less than a million years old, most still hidden from optical telescopes by the pervasive stardust. The chaotic environment may be similar to one in which our own Sun formed over 4.5 billion years ago.

09/11/2021

ASTRONOMY - A Waterfall and the Milky Way

 2021 November 1

The picture shows a waterfall under a night sky 
dominated by the arch of our Milky Way Galaxy. 
Please see the explanation for more detailed information.

A Waterfall and the Milky Way
Image Credit & Copyright: Xie Jie

Explanation: The dream was to capture both the waterfall and the Milky Way together. Difficulties included finding a good camera location, artificially illuminating the waterfall and the surrounding valley effectively, capturing the entire scene with numerous foreground and background shots, worrying that fireflies would be too distracting, keeping the camera dry, and avoiding stepping on a poisonous snake. Behold the result -- captured after midnight in mid-July and digitally stitched into a wide-angle panorama. The waterfall is the picturesque Zhulian waterfall in the Luoxiao Mountains in eastern Hunan ProvinceChina. The central band of our Milky Way Galaxy crosses the sky and shows numerous dark dust filaments and colorful nebulas. Bright stars dot the sky -- all residing in the nearby Milky Way -- including the Summer Triangle with bright Vega visible above the Milky Way's arch. After capturing all 78 component exposures for you to enjoy, the photographer and friends enjoyed the view themselves for the rest of the night.

08/11/2021

ASTRONOMY - A Filament Leaps from the Sun

 2021 November 8

A Filament Leaps from the Sun
Video Credit & Copyright: Stéphane Poirier

Explanation: Why, sometimes, does part of the Sun's atmosphere leap into space? The reason lies in changing magnetic fields that thread through the Sun's surface. Regions of strong surface magnetism, known as active regions, are usually marked by dark sunspots. Active regions can channel charged gas along arching or sweeping magnetic fields -- gas that sometimes falls backsometimes escapes, and sometimes not only escapes but impacts our Earth. The featured one-hour time-lapse video -- taken with a small telescope in France -- captured an eruptive filament that appeared to leap off the Sun late last month. The filament is huge: for comparison, the size of the Earth is shown on the upper left. Just after the filament lifted off, the Sun emitted a powerful X-class flare while the surface rumbled with a tremendous solar tsunami. A result was a cloud of charged particles that rushed into our Solar System but mostly missed our Earth -- this time. However, enough solar plasma did impact our Earth's magnetosphere to create a few faint auroras.

07/11/2021

ASTRONOMY - A Rorschach Aurora

 2021 October 30

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A Rorschach Aurora
Image Credit & Copyright: Göran Strand

Explanation: If you see this as a monster's face, don't panic. It's only pareidolia, often experienced as the tendency to see faces in patterns of light and shadow. In fact, the startling visual scene is actually a 180 degree panorama of Northern Lights, digitally mirrored like inkblots on a folded piece of paper. Frames used to construct it were captured on a September night from the middle of a waterfall-crossing suspension bridge in Jamtland, Sweden. With geomagnetic storms triggered by recent solar activity, auroral displays could be very active at planet Earth's high latitudes in the coming days. But if you see a monster's face in your own neighborhood tomorrow night, it might just be Halloween.

06/11/2021

ASTRONOMY - Road to the Galactic Center

 2021 October 25

The picture shows the a composite image of Monument Valley, Utah, USA 
in the foreground, and the plane of the Milky Way Galaxy including 
the Galactic Center in the background. 
Please see the explanation for more detailed information.

Road to the Galactic Center
Image Credit & Copyright: Michael Abramyan

Explanation: Does the road to our galaxy's center go through Monument Valley? It doesn't have to, but if your road does -- take a picture. In this case, the road is US Route 163 and iconic buttes on the Navajo National Reservation populate the horizon. The band of Milky Way Galaxy stretches down from the sky and appears to be a continuation of the road on Earth. Filaments of dust darken the Milky Way, in contrast to billions of bright stars and several colorful glowing gas clouds including the Lagoon and Trifid nebulas. The featured picture is a composite of images taken with the same camera and from the same location -- Forest Gump Point in UtahUSA. The foreground was taken just after sunset in early September during the blue hour, while the background is a mosaic of four exposures captured a few hours later.

05/11/2021

ASTRONOMY - Lucy Launches to Eight Asteroids

 2021 October 20

The picture shows the NASA's Lucy mission
launching from Cape Canaveral, Florida. 
Please see the explanation for more detailed information.

Lucy Launches to Eight Asteroids
Image Credit & Copyright: John Kraus

Explanation: Why would this mission go out as far as Jupiter -- but then not visit Jupiter? Lucy's plan is to follow different leads about the origin of our Solar System than can be found at Jupiter -- where Juno now orbits. Jupiter is such a massive planet that its gravity captures numerous asteroids that orbit the Sun ahead of it -- and behind. These trojan asteroids formed all over our Solar System and some may have been trapped there for billions of years. Flying by these trojan asteroids enables studying them as fossils that likely hold unique clues about our early Solar System. Lucy, named after a famous fossil skeleton which was named after a famous song, is scheduled to visit eight asteroids from 2025 to 2033. Pictured, Lucy's launch was captured with reflection last week aboard a powerful Atlas V rocket from Cape CanaveralFloridaUSA.

04/11/2021

ASTRONOMY - Earthshine Moon over Sicily

2021 October 18
The picture shows the sky over Sicily, Italy earlier this month
featuring a crescent moon with Earthshine, Venus, and Antares.
Please see the explanation for more detailed information.

Earthshine Moon over Sicily
Image Credit & Copyright: Dario Giannobile

Explanation: Why can we see the entire face of this Moon? When the Moon is in a crescent phase, only part of it appears directly illuminated by the Sun. The answer is earthshine, also known as earthlight and the da Vinci glow. The reason is that the rest of the Earth-facing Moon is slightly illuminated by sunlight first reflected from the Earth. Since the Earth appears near full phase from the Moon -- when the Moon appears as a slight crescent from the Earth -- earthshine is then near its brightest. Featured here in combined, consecutively-taken, HDR images taken earlier this month, a rising earthshine Moon was captured passing slowly near the planet Venus, the brightest spot near the image center. Just above Venus is the star Dschubba (catalogued as Delta Scorpii), while the red star on the far left is Antares. The celestial show is visible through scenic cloud decks. In the foreground are the lights from Palazzolo Acreide, a city with ancient historical roots in SicilyItaly

MUSIC - Richard Wagner - The ride of Walkyries

"The ride of Walkyries"

03/11/2021

ASTRONOMY - Fireball over Lake Louise

 2021 October 12

The picture shows a bright meteor fireball 
over Lake Louise in Alberta, Canada. 
Please see the explanation for more detailed information.

Fireball over Lake Louise
Image Credit & Copyright: Hao Qin

Explanation: What makes a meteor a fireball? First of all, everyone agrees that a fireball is an exceptionally bright meteor. Past that, the International Astronomical Union defines a fireball as a meteor brighter than apparent magnitude -4, which corresponds (roughly) to being brighter than any planet -- as well as bright enough to cast a human-noticeable shadow. Pictured, an astrophotographer taking a long-duration sky image captured by accident the brightest meteor he had ever seen. Clearly a fireball, the disintegrating space-rock created a trail so bright it turned night into day for about two seconds earlier this month. The fireball has been artificially dimmed in the featured image to bring up foreground Lake Louise in AlbertaCanada. Although fireballs are rare, many people have been lucky enough to see them. If you see a fireball, you can report it. If more than one person recorded an image, the fireball might be traceable back to the Solar System body from which it was ejected.

02/11/2021

ASTRONOMY - Juno Flyby of Ganymede and Jupiter

Juno Flyby of Ganymede and Jupiter
Video Credit: Images: NASAJPL-CaltechSWRIMSSS;
Animation: Koji KuramuraGerald Eichstädt, Mike Stetson; Music: Vangelis

Explanation: What would it be like to fly over the largest moon in the Solar System? In June, the robotic Juno spacecraft flew past Jupiter's huge moon Ganymede and took images that have been digitally constructed into a detailed flyby. As the featured video begins, Juno swoops over the two-toned surface of the 2,000-km wide moon, revealing an icy alien landscape filled with grooves and craters. The grooves are likely caused by shifting surface plates, while the craters are caused by violent impacts. Continuing on in its orbit, Juno then performed its 34th close pass over Jupiter's clouds. The digitally-constructed video shows numerous swirling clouds in the north, colorful planet-circling zones and bands across the middle -- featuring several white-oval clouds from the String of Pearls, and finally more swirling clouds in the south. Next September, Juno is scheduled to make a close pass over another of Jupiter's large moons: Europa.

SANTé/MEDECINE - Virus et bactéries mortels - Le virus de la rage

Grâce aux travaux de Louis Pasteur , la rage a très nettement reculé dans le monde. On dénombre tout de même plus de 50.000 morts humains s...