This intergalactic skyscape features a peculiar system of galaxies cataloged as Arp 227 some 100 million light-years distant. Swimming within the boundaries of the constellation Pisces, Arp 227 consists of the two galaxies prominent right of center, the curious shell galaxy NGC 474 and its blue, spiral-armed neighbor NGC 470. The faint, wide arcs or shells of NGC 474 could have been formed by a gravitational encounter with neighbor NGC 470. Alternately the shells could be caused by a merger with a smaller galaxy producing an effect analogous to ripples across the surface of a pond. The large galaxy on the top lefthand side of the deep image, NGC 467, appears to be surrounded by faint shells too, evidence of another interacting galaxy system. Intriguing background galaxies are scattered around the field that also includes spiky foreground stars. Of course, those stars lie well within our own Milky Way Galaxy. The field of view spans 25 arc minutes or about 1/2 degree on the sky.

This exciting and unfamiliar view of the Orion Nebula is a visualization based on astronomical data and movie rendering techniques. Up close and personal with a famous stellar nursery normally seen from 1,500 light-years away, the digitally modeled frame transitions from a visible light representation based on Hubble data on the left to infrared data from the Spitzer Space Telescope on the right. The perspective at the center looks along a valley over a light-year wide, in the wall of the region's giant molecular cloud. Orion's valley ends in a cavity carved by the energetic winds and radiation of the massive central stars of the Trapezium star cluster. The single frame is part of a multiwavelength, three-dimensional video that lets the viewer experience an immersive, three minute flight through the Great Nebula of Orion.

Lorsque Neil Armstrong et Buzz Aldrin ont pour la première fois foulé la surface de la Lune en 1969, ils y ont déposé des réflecteurs. Ces structures munies de miroirs sont, depuis, utilisées pour mesurer la distance Terre-Lune au moyen d’un laser tiré depuis la Terre. Depuis une décennie, les chercheurs ont essayé de réaliser un autre exploit : faire rebondir un laser sur un engin spatial orbitant la Lune, le Lunar Reconnaissance Orbiter. Et récemment, ils ont annoncé avoir réussi à plusieurs reprises. Des résultats qui pourraient aider à mieux comprendre la dégradation progressive des miroirs laissés sur la Lune.

Joli :-)

Lorsqu'il a réalisé la première sortie extravéhiculaire de l'Histoire, Alexei Leonov a rencontré un imprévu de taille. Sa combinaison s'est gonflée de manière anormale, l'empêchant de rentrer dans le sas. Il a alors décidé de vider en partie l'air de son scaphandre et de rentrer à l'envers !

En contrevenant aux ordres et au plan prévu, il choisit seul d’ouvrir une valve de sa combinaison pour baisser la pression à environ 1/3 de celle sur Terre. Il a également improvisé une rentrée dans la capsule la tête la première et retiré son casque plus tôt que prévu.

Wouaouh !

La nébuleuse de la trompe d'éléphant

La carte temps réel des satellites StarLink.

Whouaou ...

What is creating the structure in Comet NEOWISE's tails? Of the two tails evident, the blue ion tail on the left points directly away from the Sun and is pushed out by the flowing and charged solar wind. Structure in the ion tail comes from different rates of expelled blue-glowing ions from the comet's nucleus, as well as the always complex and continually changing structure of our Sun's wind. Most unusual for Comet C/2020 F3 (NEOWISE), though, is the wavy structure of its dust tail. This dust tail is pushed out by sunlight, but curves as heavier dust particles are better able to resist this light pressure and continue along a solar orbit. Comet NEOWISE's impressive dust-tail striations are not fully understood, as yet, but likely related to rotating streams of sun-reflecting grit liberated by ice melting on its 5-kilometer wide nucleus. The featured 40-image conglomerate, digitally enhanced, was captured three days ago through the dark skies of the Gobi Desert in Inner Mongolia, China. Comet NEOWISE will make it closest pass to the Earth tomorrow as it moves out from the Sun. The comet, already fading but still visible to the unaided eye, should fade more rapidly as it recedes from the Earth.