Contributor Posts

NASA Astronomy Picture of the Day:

Jupiter looks sharp in these two rooftop telescope images. Both were captured last year on November 17 from Singapore, planet Earth, about two weeks after Jupiter's 2023 opposition. Climbing high in midnight skies the giant planet was a mere 33.4 light-minutes from Singapore. That's about 4 astronomical units away. Jupiter's planet girdling dark belts and light zones are visible in remarkable detail, along with the giant world's whitish oval vortices. Its signature Great Red Spot is prominent in the south. Jupiter rotates rapidly on its axis once every 10 hours. So, based on video frames taken only 15 minutes apart, these images form a stereo pair. Look at the center of the pair and cross your eyes until the separate images come together to see the 3D effect. Of course Jupiter is now not far from its 2024 opposition. Planet Earth is set to pass between the Solar System's ruling gas giant and the Sun on December 7.

Photo by Marco Lorenzi

Trier, Alter Krahn on the Mosel.

Agnes Monkelbaan, CC BY-SA 4.0, via Wikimedia Commons. View source.

NASA Astronomy Picture of the Day:

Does the Sun return to the same spot on the sky every day?  No.  A more visual answer is an analemma, a composite of sky images taken at the same time and from the same place over a year.  At completion, you can see that the Sun makes a figure 8 on the sky. The featured unusual analemma does not, however, picture the Sun directly: it was created by looking in the opposite direction. All that was required was noting where the shadow of an edge of a house was in the driveway every clear day at the same time. Starting in March in Falcon, Colorado, USA, the photographer methodically marked the shadow's 1 pm location. In one frame you can even see the photographer himself. Although this analemma will be completed in 2025, you can start drawing your own driveway analemma -- using no fancy equipment -- as soon as today.

Video by Nick Wright

Early 12th-century Romanesque apsis of Notre-Dame-et-Sainte-Barbe de Savigny, Manche, France, with 14th-century murals presenting scenes from the martyrdom of St. Barbara. Her feast day is today on 4 December.

Andreas F. Borchert, CC BY-SA 4.0, via Wikimedia Commons. View source.

NASA Astronomy Picture of the Day:

If you could stand on Mars -- what might you see? You might look out over a vast orange landscape covered with rocks under a dusty orange sky, with a blue-tinted Sun over the horizon, and odd-shaped water clouds hovering high overhead. This was just the view captured last March by NASA's rolling explorer, Perseverance. The orange coloring is caused by rusted iron in the Martian dirt, some of which is small enough to be swept up by winds into the atmosphere. The blue tint near the rising Sun is caused by blue light being preferentially scattered out from the Sun by the floating dust. The light-colored clouds on the right are likely composed of water-ice and appear high in the Martian atmosphere. The shapes of some of these clouds are unusual for Earth and remain a topic of research.

"In pursuit of knowledge, the evolution of humanity ranks with the origins of life and the universe. And yet, except when an exciting find hits the headlines, paleoanthropology and its related fields have gained far less scientific support and funding – particularly for scientists and institutions based in the African countries where so many landmark discoveries have occurred". More at The Conversation ➜ 

NASA Astronomy Picture of the Day:

This galaxy is unusual for how many stars it seems that you can see. Stars are so abundantly evident in this deep exposure of the spiral galaxy NGC 300 because so many of these stars are bright blue and grouped into resolvable bright star clusters. Additionally, NGC 300 is so clear because it is one of the closest spiral galaxies to Earth, as light takes only about 6 million years to get here. Of course, galaxies are composed of many more faint stars than bright, and even more of a galaxy's mass is attributed to unseen dark matter. NGC 300 spans nearly the same amount of sky as the full moon and is visible with a small telescope toward the southern constellation of the Sculptor. The featured image was captured in October from Rio Hurtado, Chile and is a composite of over 20 hours of exposure.

Photo by Daniel Stern

Photo art based on a photograph of a Ferris wheel in Dülmen, 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.