PRATIQUE - Repasser facilement une chemise

PEINTURE SPACE ART - Tempête martienne

 

Tempête martienne 

Crédit : Luděk Pešek

ASTRONOMY - Pillars of the Eagle Nebula in Infrared

 2021 March 7

Pillars of the Eagle Nebula in Infrared
Image Credit: NASA, ESA, Hubble, HLA; Processing: Luis Romero

Explanation: Newborn stars are forming in the Eagle Nebula. Gravitationally contracting in pillars of dense gas and dust, the intense radiation of these newly-formed bright stars is causing surrounding material to boil away. This image, taken with the Hubble Space Telescope in near infrared light, allows the viewer to see through much of the thick dust that makes the pillars opaque in visible light. The giant structures are light years in length and dubbed informally the Pillars of Creation. Associated with the open star cluster M16, the Eagle Nebula lies about 6,500 light years away. The Eagle Nebula is an easy target for small telescopes in a nebula-rich part of the sky toward the split constellation Serpens Cauda (the tail of the snake).

ASTRONOMY - A Little Like Mars

 2021 March 5

A Little Like Mars
Image Credit & Copyright: Robert Barsa

Explanation: The surface of this planet looks a little like Mars. It's really planet Earth though. In a digitally stitched little planet projection, the 360 degree mosaic was captured near San Pedro in the Chilean Atacama desert. Telescopes in domes on the horizon are taking advantage of the region's famously dark, clear nights. Taken in early December, a magnificent Milky Way arcs above the horizon for almost 180 degrees around the little planet with Orion prominent in the southern sky. A familiar constellation upside down for northern hemisphere skygazers, Orion shares that southern December night almost opposite the Large and Small Magellanic clouds. But the Red Planet itself is the brightest yellowish celestial beacon in this little planet sky.

PRATIQUE - Comment faire les symboles sur un clavier

 

ASTRONOMY - Mars in Taurus

 2021 March 4

Mars in Taurus
Image Credit & Copyright: Petr Horalek / Institute of Physics in Opava

Explanation: You can spot Mars in the evening sky tonight. Now home to the Perseverance rover, the Red Planet is presently wandering through the constellation Taurus, close on the sky to the Seven Sisters or Pleiades star cluster. In fact this deep, widefield view of the region captures Mars near its closest conjunction to the Pleiades on March 3. Below center, Mars is the bright yellowish celestial beacon only about 3 degrees from the pretty blue star cluster. Competing with Mars in color and brightness, Aldebaran is the alpha star of Taurus. The red giant star is toward the lower left edge of the frame, a foreground star along the line-of-sight to the more distant Hyades star cluster. Otherwise too faint for your eye to see, the dark, dusty nebulae lie along the edge of the massive Perseus molecular cloud, with the striking reddish glow of NGC 1499, the California Nebula, at the upper right.

ASTRONOMY - Stars over an Erupting Volcano

 2021 March 3

Stars over an Erupting Volcano
Image Credit & Copyright: Giuseppe Vella

Explanation: Mt. Etna has been erupting for hundreds of thousands of years. Located in Sicily, Italy, the volcano produces lava fountains over one kilometer high. Mt. Etna is not only one of the most active volcanoes on Earth, it is one of the largest, measuring over 50 kilometers at its base and rising nearly 3 kilometers high. Pictured erupting last month, a lava plume shoots upwards, while hot lava flows down the volcano's exterior. Likely satellite trails appear above, while ancient stars dot the sky far in the distance. This volcanic eruption was so strong that nearby airports were closed to keep planes from flying through the dangerous plume. The image foreground and background were captured consecutively by the same camera and from the same location.

PRATIQUE - La magie du calcul !

 

ASTRONOMY - Ingenuity: A Mini-Helicopter Now on Mars

 2021 March 2

Ingenuity: A Mini-Helicopter Now on Mars
Illustration Credit: NASA, JPL-Caltech, Mars 2020 - Perseverance

Explanation: What if you could fly around Mars? NASA may have achieved that capability last month with the landing of Perseverance, a rover which included a small flight-worthy companion called Ingenuity, nicknamed Ginny. Even though Ginny is small -- a toaster-sized helicopter with four long legs and two even-longer (1.2-meter) rotors, she is the first of her kind -- there has never been anything like her before. After being deployed, possibly in April, the car-sized Perseverance ("Percy") will back away to give Ginny ample room to attempt her unprecedented first flight. In the featured artistic illustration, Ginny's long rotors are depicted giving her the lift she needs to fly into the thin Martian atmosphere and explore the area near Perseverance. Although Ingenuity herself will not fly very far, she is a prototype for all future airborne Solar-System robots that may fly far across not only Mars, but Titan.

ASTRONOMY - The Pelican Nebula in Red and Blue

2021 March 1

The Pelican Nebula in Red and Blue
Image Credit & Copyright: M. Petrasko, M. Evenden, U. Mishra (Insight Obs.)

Explanation: The Pelican Nebula is changing. The entire nebula, officially designated IC 5070, is divided from the larger North America Nebula by a molecular cloud filled with dark dust. The Pelican, however, is particularly interesting because it is an unusually active mix of star formation and evolving gas clouds. The featured picture was processed to bring out two main colors, red and blue, with the red dominated by light emitted by interstellar hydrogen. Ultraviolet light emitted by young energetic stars is slowly transforming cold gas in the nebula to hot gas, with the advancing boundary between the two, known as an ionization front, visible in bright red across the image center. Particularly dense tentacles of cold gas remain. Millions of years from now this nebula might no longer be known as the Pelican, as the balance and placement of stars and gas will surely leave something that appears completely different.