Nombre total de pages vues
20/03/2024
SANTé/MEDECINE - La tomographie : La caméra TEP : voir le cerveau grâce à des traceurs radioactifs
SANTé/MEDECINE - HISTOIRE - 1609 : invention du microscope
INVENTEURS TUéS PAR LEURS INVENTIONS - Le parachute de Franz Reichell
ASTRONOMY - The Eyes in Markarian's Galaxy Chain
2024 March 20
Image Credit & Copyright: Mike Selby
Explanation: Across the heart of the Virgo Galaxy Cluster lies a string of galaxies known as Markarian's Chain. Prominent in Markarian's Chain are these two interacting galaxies, NGC 4438 (left) and NGC 4435 - also known as The Eyes. About 50 million light-years away, the two galaxies appear to be about 100,000 light-years apart in this sharp close-up, but have likely approached to within an estimated 16,000 light-years of each other in their cosmic past. Gravitational tides from the close encounter have ripped away at their stars, gas, and dust. The more massive NGC 4438 managed to hold on to much of the material torn out in the collision, while material from the smaller NGC 4435 was more easily lost. The remarkably deep image of this crowded region of the universe also includes many more distant background galaxies.
19/03/2024
INVENTEURS TUES PAR LEURS INVENTIONS - Otto Lilienthal - Pionnier de l'aviation
SANTé/MEDECINE - Le fonctionnement de l'oeil humain - Le muscle droit
SANTé/MEDECINE - Cancer du sein - Attention à un gonflement autour de l’aisselle ou du sein
ASTRONOMY - A Picturesque Equinox Sunset
2024 March 19
Image Credit & Copyright: Alan Dyer, Amazingsky.com, TWAN
Explanation: What's that at the end of the road? The Sun. Many towns have roads that run east-west, and on two days each year, the Sun rises and sets right down the middle. Today, in some parts of the world (tomorrow in others), is one of those days: an equinox. Not only is this a day of equal night ("aequus"-"nox") and day time, but also a day when the sun rises precisely to the east and sets due west. Displayed here is a picturesque rural road in Alberta, Canada that runs approximately east-west. The featured image was taken during the September Equinox of 2021, but the geometry remains the same every year. In many cultures, this March equinox is taken to be the first day of a season, typically spring in Earth's northern hemisphere, and autumn in the south. Does your favorite street run east-west? Tonight, at sunset, you can find out with a quick glance.
18/03/2024
SANTé/MEDECINE - Le fonctionnement de l'oeil humain - L'iris, la partie colorée de l'œil
SANTé/MEDECINE - Cancer du sein : attention à ces 5 symptômes - Un écoulement du mamelon
ASTRONOMY - Christmas Tree Aurora
2024 December 23 Christmas Tree Aurora Image Credit & Copyright: Jingyi Zhang Explanation: It was December and the sky lit up like a ...
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2021 May 11 Lightning and Orion Beyond Uluru Image Credit & Copyright: Park Liu Explanation: What's happening behind Uluru? A Un...
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Extraordinary Solar Halos Image Credit & Copyright : Magnus Edback Explanation: Welcome to the December Solstice, the first...