Photo of the Day What's happening in the sky? Lightning. The most commonly seen type of lightning involves flashes of bright white light between clouds. Over the past 50 years, though, other types of upper-atmospheric lightning have been confirmed, including tentacled red sprites and ringed ELVES. Although both last only a small fraction of [...]
Photo of the Day When the Moon is at its first quarter phase, the Sun rises along the Montes Caucasus as seen from the lunar surface. The lunar mountain range casts the magnificent, spire-like shadows in this telescopic view from planet Earth, looking along the lunar terminator or the boundary between lunar night and [...]
Photo of the Day Jupiter, the Solar System's ruling gas giant, is the brightest celestial beacon at the center of this composite night skyscape. The scene was constructed by selecting the 40 exposures containing meteors from about 500 exposures made on the nights of December 13 and 14, near peak activity for this year's [...]
Photo of the Day What’s happening over that tree? Two very different things. On the left is the Andromeda galaxy, an object that is older than humanity and will last billions of years into the future. Andromeda (M31) is similar in size and shape to our own Milky Way Galaxy. On the right is [...]
Photo of the Day Where are all of these meteors coming from? In terms of direction on the sky, the pointed answer is the constellation of Gemini. That is why the major meteor shower in December is known as the Geminids -- because shower meteors all appear to come from a radiant toward Gemini. [...]
Photo of the Day What would it be like to fly over the largest moon in the Solar System? In 2021, the robotic Juno spacecraft flew past Jupiter's huge moon Ganymede and took images that have been digitally constructed into a detailed flyby. As the featured video begins, Juno swoops over the two-toned surface [...]
Photo of the Day On December 5, 2022, a camera on board the uncrewed Orion spacecraft captured this view as Orion approached its return powered flyby of the Moon. Beyond one of Orion's extended solar arrays lies dark, smooth, terrain along the western edge of the Oceanus Procellarum. Prominent on the lunar nearside Oceanus [...]
Photo of the Day This cosmic close-up looks deep inside the Soul Nebula. The dark and brooding dust clouds outlined by bright ridges of glowing gas are cataloged as IC 1871. About 25 light-years across, the telescopic field of view spans only a small part of the much larger Heart and Soul nebulae. At [...]
Photo of the Day Many wonders are visible when flying over the Earth at night. Such visual spectacles occur every day for astronauts in low Earth orbit, but the featured video captured several from the International Space Station (ISS) in 2011 and set them to rousing music. Passing below are white clouds, orange city [...]
Photo of the Day It is still not known why the Sun's light is missing some colors. Here are all the visible colors of the Sun, produced by passing the Sun's light through a prism-like device. The spectrum was created at the McMath-Pierce Solar Observatory and shows, first off, that although our white-appearing Sun [...]
