Nombre total de pages vues
02/11/2022
AVIATION IMAGINEE - D'immenses avions pour des vacances au pôle Nord
ASTRONOMY - A Partial Eclipse of an Active Sun
2022 November 2
Video Credit: Ralf Burkart; h/t Maciej Libert (AG)
Explanation: Watch for three things in this unusual eclipse video. First, watch for a big dark circle to approach from the right to block out more and more of the Sun. This dark circle is the Moon, and the video was made primarily to capture this partial solar eclipse last week. Next, watch a large solar prominence hover and shimmer over the Sun's edge. A close look will show that part of it is actually falling back to the Sun. The prominence is made of hot plasma that is temporarily held aloft by the Sun's changing magnetic field. Finally, watch the Sun's edge waver. What is wavering is a dynamic carpet of hot gas tubes rising and falling through the Sun's chromosphere -- tubes known as spicules. The entire 4-second time-lapse video covers a time of about ten minutes, although the Sun itself is expected to last another 5 billion years.
01/11/2022
ASTRONOMY - Night on a Spooky Planet
Image Credit & Copyright: Stéphane Vetter (Nuits sacrées)
Explanation: What spooky planet is this? Planet Earth of course, on a dark and stormy night in 2013 at Hverir, a geothermally active area along the volcanic landscape in northeastern Iceland. Triggered by solar activity, geomagnetic storms produced the auroral display in the starry night sky. The ghostly towers of steam and gas are venting from fumaroles and danced against the eerie greenish light. For now, auroral apparitions are increasing as our Sun approaches a maximum in its 11 year solar activity cycle. And pretty soon, ghostly shapes may dance in your neighborhood too.
31/10/2022
ASTRONOMY - LDN 43: The Cosmic Bat Nebula
2022 October 31
Image Credit & Copyright: Mark Hanson and Mike Selby; Text: Michelle Thaller (NASA's GSFC)
Explanation: What is the most spook-tacular nebula in the galaxy? One contender is LDN 43, which bears an astonishing resemblance to a vast cosmic bat flying amongst the stars on a dark Halloween night. Located about 1400 light years away in the constellation Ophiuchus, this molecular cloud is dense enough to block light not only from background stars, but from wisps of gas lit up by the nearby reflection nebula LBN 7. Far from being a harbinger of death, this 12-light year-long filament of gas and dust is actually a stellar nursery. Glowing with eerie light, the bat is lit up from inside by dense gaseous knots that have just formed young stars.
29/10/2022
ASTRONOMY - Seven Years of Halley Dust
2022 October 28
Image Credit & Copyright: Petr Horalek / Institute of Physics in Opava
Explanation: History's first known periodic comet Halley (1P/Halley) returns to the inner Solar System every 75 years or so. The famous comet made its last appearance to the naked-eye in 1986. But dusty debris from Comet Halley can be seen raining through planet Earth's skies twice a year during two annual meteor showers, the Eta Aquarids in May and the Orionids in October. Including meteors near the shower maximum on October 21, this composite view compiles Orionid meteors captured from years 2015 through 2022. About 47 bright meteors are registered in the panoramic night skyscape. Against a starry background extending along the Milky Way, the Orionid meteors all seem to radiate from a point just north of Betelgeuse in the familiar constellation of the Hunter. In the foreground are mountains in eastern Slovakia near the city of Presov.
27/10/2022
ASTRONOMIE - Comprendre Mars
ASTRONOMY - Sunset, Moonset, Taj Mahal
2022 October 27
Image Credit & Copyright: Neelam and Ajay Talwar (TWAN)
Explanation: On October 25th, Sun and New Moon set together as seen from Agra, India. Their close conjunction near the western horizon, a partial solar eclipse, was captured in this elevated view in hazy skies near the solitary dome of the Taj Mahal. Of course, the partial solar eclipse was also seen from most of Europe, northern Africa, the Middle East, and western parts of Asia. This eclipse was the last of two solar eclipses (both partial eclipses) in 2022. But the next Full Moon will slide through planet Earth's shadow on November 7/8, in a total lunar eclipse.
26/10/2022
MICROPHOTOGRAPHIE - Granulite et graphite
MACROPHOTOGRAPHIE - Miki Asai - En attendant que vienne une fourmi
AVIATION IMAGINEE - La voiture volante individuelle
ASTRONOMY - The Local Fluff
2024 December 22 The Local Fluff Illustration Credit: NASA , SVS , Adler , U. Chicago , Wesleyan Explanation: The stars are not alone...
-
2021 May 11 Lightning and Orion Beyond Uluru Image Credit & Copyright: Park Liu Explanation: What's happening behind Uluru? A Un...
-
Extraordinary Solar Halos Image Credit & Copyright : Magnus Edback Explanation: Welcome to the December Solstice, the first...