Mu Cephei is a very large star. An M-class supergiant some 1500 times the size of the Sun, it is one of the largest stars visible to the unaided eye, and even one of the largest in the entire Galaxy. If it replaced the Sun in our fair Solar System, Mu Cephei would easily engulf […]
It’s easy to get swept up in the swirling starry arms of this intermediate spiral galaxy, NGC 4654, in the constellation Virgo. The galaxy has a bright center and is labeled “intermediate” because it has characteristics of both unbarred and barred spirals. NGC 4654 is just north of the celestial equator, making it visible from […]
What’s happening in the lower arm of this spiral galaxy? A supernova. Last month, supernova SN 2023rve was discovered with UAE’s Al-Khatim Observatory and later found to be consistent with the death explosion of a massive star, possibly leaving behind a black hole. Spiral galaxy NGC 1097 is a relatively close 45 million light years […]
The Great Nebula in Orion has hidden stars. To the unaided eye in visible light, it appears as a small fuzzy patch in the constellation of Orion. But this image was taken by the Webb Space Telescope in a representative-color composite of red and very near infrared light. It confirms with impressive detail that the […]
Yes, but have you ever seen a sunrise like this? Here, after initial cloudiness, the Sun appeared to rise in two pieces and during a partial eclipse in 2019, causing the photographer to describe it as the most stunning sunrise of his life. The dark circle near the top of the atmospherically-reddened Sun is the […]
What’s that in front of the Sun? The closest object is an airplane, visible just below the Sun’s center and caught purely by chance. Next out are numerous clouds in Earth’s atmosphere, creating a series of darkened horizontal streaks. Farther out is Earth’s Moon, seen as the large dark circular bite on the upper right. […]
This picture of Andromeda shows not only where stars are now, but where stars will be. The big, beautiful Andromeda Galaxy, M31, is a spiral galaxy a mere 2.5 million light-years away. Image data from space-based and ground-based observatories have been combined here to produce this intriguing composite view of Andromeda at wavelengths both inside […]
“I think the experience of putting yourself in an uncomfortable environment and coming at the other end with lessons learned is always positive. Trying to expand the windows of where you feel comfortable gives you a chance to know yourself better.” — Alfonso Davila, Research Scientist, Exobiology Branch, NASA’s Ames Research Center via NASA
How big is our universe? This question, among others, was debated by two leading astronomers in 1920 in what has since become known as astronomy’s Great Debate. Many astronomers then believed that our Milky Way Galaxy was the entire universe. Many others, though, believed that our galaxy was just one of many. In the Great […]
This feature looks a bit like a bear’s face. What is it really? There’s a hill with a V-shaped collapse structure (the nose), two craters (the eyes), and a circular fracture pattern (the head). The circular fracture pattern might be due to the settling of a deposit over a buried impact crater. Maybe the nose […]