NASA’s Astronomy Picture of the Day

This computer simulation visualizes dark matter filaments and concentrations of ordinary matter in a cosmic web. We explore the gravitational evidence behind the model, what simulations test, and why dark matter's physical identity remains unknown. My podcasts are available in video form through this YouTube Channel. This Podcast is an authorized New Media Mirror Site for APOD. You can access the image and website directly at: Astronomy Picture of the Day. You can use the archive link above th

Rosetta's selfie was taken by a camera on its still-attached Philae lander, with comet 67P beyond the spacecraft's solar array. Two exposures reveal the contrasting brightness of the scene and introduce the mission's complementary observations from nearby space and the comet's surface. My podcasts are available in video form through this YouTube Channel. This Podcast is an authorized New Media Mirror Site for APOD. You can access the image and website directly at: Astronomy Picture of the Day.

Andromeda hangs low above Australian hills in this composite of tracked, stacked sky exposures and a separate foreground photograph. The scene shows how observing latitude and photographic techniques shape our view of a neighboring galaxy. My podcasts are available in video form through this YouTube Channel. This Podcast is an authorized New Media Mirror Site for APOD. You can access the image and website directly at: Astronomy Picture of the Day. You can use the archive link above the image t

This illustration depicts a white dwarf whose spectrum predicts a green appearance to human eyes. Its dense, sodium-rich atmosphere changes the balance of escaping light, revealing an unusual exception to familiar stellar colors. My podcasts are available in video form through this YouTube Channel. This Podcast is an authorized New Media Mirror Site for APOD. You can access the image and website directly at: Astronomy Picture of the Day. You can use the archive link above the image to select t

Deep imaging around the Ghosts of Cassiopeia reveals three faint oxygen-emitting structures. Their possible origins show the difference between discovering an object and establishing what powers it. My podcasts are available in video form through this YouTube Channel. This Podcast is an authorized New Media Mirror Site for APOD. You can access the image and website directly at: Astronomy Picture of the Day. You can use the archive link above the image to select the photo corresponding to the d

A partial rainbow and a golden fan of anticrepuscular rays make sunlight seem to originate from the wrong side of the sky. Raindrops, cloud shadows, and perspective explain why the real Sun is behind the camera. My podcasts are available in video form through this YouTube Channel. This Podcast is an authorized New Media Mirror Site for APOD. You can access the image and website directly at: Astronomy Picture of the Day. You can use the archive link above the image to select the photo correspon