Magazine Posts

NASA Astronomy Picture of the Day:

Is this what will become of our Sun? Quite possibly. The first hint of our Sun's future was discovered inadvertently in 1764. At that time, Charles Messier was compiling a list of diffuse objects not to be confused with comets. The 27th object on Messier's list, now known as M27 or the Dumbbell Nebula, is a planetary nebula, one of the brightest planetary nebulas on the sky and visible with binoculars toward the constellation of the Fox (Vulpecula). It takes light about 1000 years to reach us from M27, featured here in colors emitted by sulfur (red), hydrogen (green) and oxygen (blue). We now know that in about 6 billion years, our Sun will shed its outer gases into a planetary nebula like M27, while its remaining center will become an X-ray hot white dwarf star. Understanding the physics and significance of M27 was well beyond 18th century science, though. Even today, many things remain mysterious about planetary nebulas, including how their intricate shapes are created. APOD Year in Review: Night Sky Network Presentation for 2024

Photo by Christopher Stobie

Wedge-tailed grass finch (Emberizoides herbicola) in Terenos, Mato Grosso do Sul, Brazil.

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

NASA Astronomy Picture of the Day:

What are these bubbles frozen into Lake Baikal? Methane. Lake Baikal, a UNESCO World Heritage Site in Russia, is the world's largest (by volume), oldest, and deepest lake, containing over 20% of the world's fresh water. The lake is also a vast storehouse of methane, a greenhouse gas that, if released, could potentially increase the amount of infrared light absorbed by Earth's atmosphere, and so increase the average temperature of the entire planet. Fortunately, the amount of methane currently bubbling out is not climatologically important. It is not clear what would happen, though, were temperatures to significantly increase in the region, or if the water level in Lake Baikal were to drop. Pictured, bubbles of rising methane froze during winter into the exceptionally clear ice covering the lake. Jigsaw Challenge: Astronomy Puzzle of the Day

Photo by Kristina Makeeva

Interior of the Canterbury Cathedral. Thomas Becket was martyred at the altar on this date in 1170. Today is Thomas Becket's feast day.

Diliff, CC BY-SA 3.0, via Wikimedia Commons. View source.

NASA Astronomy Picture of the Day:

Orion seems to come up sideways, climbing over a distant mountain range in this deep skyscape. The wintry scene was captured from southern Poland on the northern hemisphere's long solstice night. Otherwise unseen nebulae hang in the sky, revealed by the camera modified to record red hydrogen-alpha light. The nebulae lie near the edge of the Orion molecular cloud and join the Hunter's familiar belt stars and bright giants Betelgeuse and Rigel. Eye of Taurus the Bull, yellowish Aldebaran anchors the V-shaped Hyades star cluster near top center. Still, near opposition in planet Earth's sky, the Solar System's ruling gas giant Jupiter is the brightest celestial beacon above this horizon's snowy peaks.

Photo by Włodzimierz Bubak

Satellite picture of the Etna volcano erupting in eastern Sicily (Italy) in December 2018.

NASA Earth Observatory images by Joshua Stevens, using Landsat data from the U.S. Geological Survey. Text by Kasha Patel., Public domain, via Wikimedia Commons. View source.

NASA Astronomy Picture of the Day:

No sudden, sharp boundary marks the passage of day into night in this gorgeous view of ocean and clouds over our fair planet Earth. Instead, the shadow line or terminator is diffuse and shows the gradual transition to darkness we experience as twilight. With the Sun illuminating the scene from the right, the cloud tops reflect gently reddened sunlight filtered through the dusty troposphere, the lowest layer of the planet's nurturing atmosphere. A clear high altitude layer, visible along the dayside's upper edge, scatters blue sunlight and fades into the blackness of space. This picture was taken from the International Space Station orbiting at an altitude of 211 nautical miles. Of course from home, you can check out the Earth Now.

The Seehornsee in the Berchtesgaden Alps. On the right the normal route to the Seehorn.

Jörg Braukmann, CC BY-SA 4.0, via Wikimedia Commons. View source.

Avram Noam Chomsky, born in 1928 is an American professor and public intellectual known for his work in linguistics, political activism, and social criticism. Chomsky is also a major figure in analytic philosophy and one of the founders of the field of cognitive science. He is a laureate professor of linguistics at the University of Arizona and an institute professor emeritus at the Massachusetts Institute of Technology (MIT). Chomsky has written more than 150 books on topics such as linguistics, war, and politics. In addition to his work in linguistics, since the 1960s. More Chomsky has been an influential voice on the American left as a consistent critic of U.S. foreign policy, contemporary capitalism, and corporate influence on political institutions and the media. More

NASA Astronomy Picture of the Day:

Viewed face-on, grand spiral galaxy NGC 5643 has a festive appearance in this colorful cosmic portrait. Some 55 million light-years distant, the galaxy extends for over 100,000 light-years, seen within the boundaries of the southern constellation Lupus. Its inner 40,000 light-years are shown in sharp detail in this composite of Hubble Space Telescope image data. The galaxy's magnificent spiral arms wind from a yellowish central region dominated by light from old stars, while the spiral arms themselves are traced by dust lanes, young blue stars and reddish star forming regions. The bright compact core of NGC 5643 is also known as a strong emitter of radio waves and X-rays. In fact, NGC 5643 is one of the closest examples of the Seyfert class of active galaxies, where vast amounts of dust and gas are thought to be falling into a central massive black hole.

Khone Phapheng Falls, Si Phan Don, Laos. Located on the Mekong River near the border with Cambodia, at 10.7 kilometres (6.6 mi) wide, it is the widest waterfall in the world.

Basile Morin, CC BY-SA 4.0, via Wikimedia Commons. View source.

NASA Astronomy Picture of the Day:

Why is there a huge eye in the sky? Diamond dust. That is an informal term for small ice crystals that form in the air and flitter to the ground. Because these crystals are geometrically shaped, they can together reflect light from the Sun or Moon to your eyes in a systematic way, causing huge halos and unusual arcs to appear. And sometimes, together the result can seem like a giant eye looking right back at you. In the featured image taken in the Ore Mountains of the Czech Republic last week, a bright Moon rising through ice fog-filled air resulted in many of these magnificent sky illusions to be visible simultaneously. Besides Moon dogs, tangent arcs, halos, and a parhelic circle, light pillars above distant lights are visible on the far left, while Jupiter and Mars can be found just inside the bottom of the 22-degree halo. Your Sky Surprise: What picture did APOD feature on your birthday? (post 1995)

Photo by Jaroslav Fous