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NASA Astronomy Picture of the Day:

Are lasers from giant telescopes being used to defend the Earth? No. Lasers shot from telescopes are now commonly used to help increase the accuracy of astronomical observations. In some directions, Earth atmosphere-induced fluctuations in starlight can indicate how the air mass over a telescope is changing, but in other directions, no bright star exists. In these directions, astronomers can create an artificial star with a laser. Subsequent observations of the artificial laser guide star can reveal information so detailed about the changing blurring effects of the Earth's atmosphere that much of it can be removed by rapidly flexing a telescope's mirror. Such adaptive optics techniques allow high-resolution ground-based observations of real stars, planets, and nebulas. Pictured here, telescopes at Paranal Observatory in Chile study a colorful sky filled with green airglow and the Magellanic Clouds on the left, red airglow on the right, and the majestic central band of our Milky Way Galaxy arching across the center.

Photo by Julien Looten

Forester kangaroo (Macropus giganteus tasmaniensis) juvenile, Upper Esk Valley, Dorset, Tasmania, Australia.

Charles J. Sharp, CC BY-SA 4.0, via Wikimedia Commons. View source.

Lance Asper on Unsplash

NASA Astronomy Picture of the Day:

What's going on inside the head of this nebula? Dubbed the Exposed Cranium Nebula for its similarity to the human brain, what created the nebula remains a mystery. One thought is that the Cranium Nebula, also known as PMR 1, is a planetary nebula surrounding a white dwarf star. In this mode, the outer atmosphere was expelled when the original Sun-like star ran out of central nuclear fuel and contracted. A competing thought is that the central star is much more massive, possibly a Wolf-Rayet star, that is ejecting gas and dust via turbulent stellar winds. Adding to the intrigue is the dark vertical central division and the thin outer gaseous shell. The featured image was taken by the Webb Space Telescope in mid- infrared light, while a second image, included as a rollover, is in near-infrared. Future observations may reveal if this brainy system will quietly just fade from view or, many years from now, suddenly erupt in a powerful supernova.

A motorcyclist in motion on the corner of W 42nd St and 6th Ave in Midtown Manhattan, New York City, on March 9, 2023. An example of kinetic art created by intentional camera movement, reminiscent of the work of Austrian-American photographer Ernst Haas (1921–1986).

Frank Schulenburg, CC BY-SA 4.0, via Wikimedia Commons. View source.

"If two friends ask you to judge a dispute, don't accept, because you will lose one friend; on the other hand, if two strangers come with the same request, accept because you will gain one friend."

St. Augustine of Hippo (354-430) An influential North African theologian and philosopher, known for works like Confessions and The City of God. He is the patron and father of the Catholic Augustinian order.

Paul Van Cotthem on Unsplash

Antelope Canyon is a slot canyon in the American Southwest. It is located on Navajo land east of Page, Arizona. It was formed by erosion of Navajo Sandstone, primarily due to flash flooding. Rainwater runs into the extensive basin above the slot canyon sections, picking up speed and sand as it rushes into the narrow passageways. I visited this wonder of nature in the summer of 2016.

NASA Astronomy Picture of the Day:

Yes, but can your tree do this? Pictured is a visual coincidence between the dark branches of a nearby tree and bright glow of a distant aurora. The beauty of the aurora -- combined with how it seemed to mimic a tree right nearby -- mesmerized the photographer to such a degree that he momentarily forgot to take pictures. When viewed at the right angle, it seemed that this tree had aurora for leaves. Fortunately, before the aurora morphed into a different overall shape, he came to his senses and captured the awe-inspiring momentary coincidence. Typically triggered by solar explosions, aurora are caused by high energy electrons impacting the Earth's atmosphere around 150 kilometers up. The unusual Earth-sky collaboration was witnessed in March of 2017 in Iceland. Sky Surprise: What picture did APOD feature on your birthday? (after 1995)

Photo by Alyn Wallace

Tower Clock manufacturer in Morez, France - Louis-Delphin Odobey Cadet. Daylight saving time begins today in much of the Western Hemisphere.

Henri Gaudichon, Public domain, via Wikimedia Commons. View source.

Ryan Tasto on Unsplash

Dreary Color