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Explore major historical events from today or any day on Kudos 365.

“There are three ways of arriving at an opinion on any subject. The first is to believe what one is told; the second is to disbelieve it; and the third is to examine the matter for oneself. The overwhelming majority of mankind practice the first method; of the remainder, the overwhelming majority practice the second; only an infinitesimal remnant practice the third.”

Source:  Bertrand Russell, Mortals and Others, Bertrand Russell’s American Essays 1931–1935, Vol. II, Essay. 37: What to Believe, p. 454 (24 August 1931)

NASA Astronomy Picture of the Day:

Is the sky the same every night? No -- the night sky changes every night in many ways. To better explore how the night sky changes, the USA's NSF and DOE commissioned the Vera C. Rubin Observatory in Cerro Pachón, Chile. In final testing before routine operations, Rubin will begin to explore these nightly changes -- slight differences that can tell us much about our amazing universe and its surprising zoo of objects. With a mirror over 8 meters across, Rubin will continually reimage the entire visible sky every few nights to discover new supernovas, potentially dangerous asteroids, faint comets, and variable stars -- as well as mapping out the visible universe's large-scale structure. Pictured, the distant central band of our Milky Way Galaxy appears to flow out from the newly operational observatory. Taken last month, the featured picture is a composite of 21 images across the night sky, capturing airglow on the horizon and the Small Magellanic Cloud galaxy on the lower left. APOD Turns 30!: Free Public Lecture in Anchorage on June 11

Clouds over the Greater Caucasus Range, along with fog and atmospheric mist. The landscape represents geological features from different geological epochs: Triassic, Jurassic, and the Oligocene. View from Mount Asbestnaya, Republic of Adygea, Caucasus Mountains.

Vyacheslav Argenberg, CC BY 4.0, via Wikimedia Commons. View source.

NASA Astronomy Picture of the Day:

Why would the sky glow like a giant repeating rainbow? Airglow. Now, air glows all of the time, but it is usually hard to see. A disturbance however -- like an approaching storm -- may cause noticeable rippling in the Earth's atmosphere. These gravity waves are oscillations in air analogous to those created when a rock is thrown in calm water. The long-duration exposure nearly along the vertical walls of airglow likely made the undulating structure particularly visible. OK, but where do the colors originate? The deep red glow likely originates from OH molecules about 87 kilometers high, excited by ultraviolet light from the Sun. The orange and green airglow is likely caused by sodium and oxygen atoms slightly higher up. The featured image was captured during a climb up Mount Pico in the Azores of Portugal. Ground lights originate from the island of Faial in the Atlantic Ocean. A spectacular sky is visible through this banded airglow, with the central band of our Milky Way Galaxy running up the image center, and M31, the Andromeda Galaxy, visible near the top left. APOD Turns 30!: Free Public Lecture in Anchorage on June 11

Photo by Miguel Claro (TWAN); Rollover Annotation: Judy Schmidt

Photo art based on a picture of a rolling gate at blast furnace 5 in the Duisburg-Nord Landscape Park, Duisburg, North Rhine-Westphalia, GermanyThe original shot used the creative technique of intentional camera movement. This image was mirrored and recomposed to achieve the symmetry effect.

Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons. View source.

Photo by Calob photography

NASA Astronomy Picture of the Day:

Wisps like this are all that remain visible of a Milky Way star. About 7,000 years ago that star exploded in a supernova, leaving the Veil Nebula. At the time, the expanding cloud was likely as bright as a crescent Moon, remaining visible for weeks to people living at the dawn of recorded history. Today, the resulting supernova remnant, also known as the Cygnus Loop, has faded and is now visible only through a small telescope directed toward the constellation of the Swan (Cygnus). The remaining Veil Nebula is physically huge, however, and even though it lies about 1,400 light-years distant, it covers over five times the size of the full Moon. The featured picture was taken in Kuwait in mid-2024 and features light emitted by hydrogen in red and oxygen in blue. In deep images of the complete Veil Nebula like this, even studious readers might not be able to identify the iconic filaments. Piece it All Together: Astronomy Puzzle of the Day

Photo by Abdullah Alharbi

A European bee-eater (Merops apiaster) in flight at Pfyn-Finges, Switzerland. This image was created by merging three successive photographs of the same bird's flight.

Giles Laurent, CC BY-SA 4.0, via Wikimedia Commons. View source.