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NASA Astronomy Picture of the Day:

Is the Helix Nebula looking at you? No, not in any biological sense, but it does look quite like an eye. The Helix Nebula is so named because it also appears that you are looking down the axis of a helix. In actuality, it is now understood to have a surprisingly complex geometry, including radial filaments and extended outer loops. The Helix Nebula (aka NGC 7293) is one of brightest and closest examples of a planetary nebula, a gas cloud created at the end of the life of a Sun-like star. The remnant central stellar core, destined to become a white dwarf star, glows in light so energetic it causes the previously expelled gas to fluoresce. The featured picture, taken in red, green, and blue but highlighted by light emitted primarily by hydrogen was created from 12 hours of exposure through a personal telescope located in Greece. A close-up of the inner edge of the Helix Nebula shows complex gas knots the origin of which are still being researched. Portal Universe: Random APOD Generator

Photo by George Chatzifrantzis

Portas da Cidade, Ponta Delgada, São Miguel Island, Azores, Portugal.

Diego Delso, CC BY-SA 4.0, via Wikimedia Commons. View source.

Photo through a microscope of crystals growing from melted sulfur. Polarized light technology. Magnification x10.

AlexmarPhoto, CC BY 4.0, via Wikimedia Commons. View source.

Aesop (620 – 564 BC) Greek fabulist and story teller

Image: Aesop  by Diego Velazquez -| Museo Del Prado

NASA Astronomy Picture of the Day:

Have you ever watched a lightning storm in awe? You're not alone. Details of what causes lightning are still being researched, but it is known that inside some clouds, internal updrafts cause collisions between ice and snow that slowly separate charges between cloud tops and bottoms. The rapid electrical discharges that are lightning soon result. Lightning usually takes a jagged course, rapidly heating a thin column of air to about three times the surface temperature of the Sun. The resulting shock wave starts supersonically and decays into the loud sound known as thunder. On average, around the world, about 6,000 lightning bolts occur between clouds and the Earth every minute. Pictured in July 2019 in a two-image composite, lightning stems from communication antennas near the top of Volcán de Agua (Volcano of Water) in Guatemala. Sky Surprise: What picture did APOD feature on your birthday? (post 1995)

Wakeboarder, Boardstock Festival in Zug, Switzerland, 2008.

Roy Egloff , CC BY-SA 4.0, via Wikimedia Commons. View source.

NASA Astronomy Picture of the Day:

Globular star cluster Omega Centauri packs about 10 million stars much older than the Sun into a volume some 150 light-years in diameter. Also known as NGC 5139, at a distance of 15,000 light-years it's the largest and brightest of 200 or so known globular clusters that roam the halo of our Milky Way galaxy. Though most star clusters consist of stars with the same age and composition, the enigmatic Omega Cen exhibits the presence of different stellar populations with a spread of ages and chemical abundances. In fact, Omega Cen may be the remnant core of a small galaxy merging with the Milky Way. With a yellowish hue, Omega Centauri's red giant stars are easy to pick out in this sharp telescopic view. A two-decade-long exploration of the dense star cluster with the Hubble Space Telescope has revealed evidence for a massive black hole near the center of Omega Centauri.

Photo by Leo Shatz

Winter Angelus Hut with Angelus Lake behind it. In the clouds, no name peak (1860m) can be seen. Picture taken during the sunset. Nelson Lakes National Park, New Zealand.

Michal Klajban, CC BY-SA 4.0, via Wikimedia Commons. View source.