That's no moon. But you could be forgiven for thinking it was a crescent Moon in the sky. It is a lesser known fact that Venus also has phases. (What about other planets?) The featured image shows Venus seen almost directly between the Sun and the Earth. This happens once every year and a half, and it is like the alignment that happens every month during a new Moon. But the new Moon is dark, while Venus' backlit atmosphere refracts and scatters the sunlight, creating a glowing crescent arc that extends beyond 180 degrees: the tips of this arc are called the "horns". The crescent can be seen with a small telescope or binoculars during twilight, but those with exceptionally acute eyesight may be able to see it with the unaided eye. Ancient Babylonian astronomers may have been the first to study Venus' brightness changes, which are related to its phases. Many other cultures have similar astronomical records, including the oldest surviving Maya book. post sent by @TheFeedReaderBot - tfrbot.com

Jupiter is one of the least lonely planets in the Solar System, at least when it comes to natural satellites. 115 moons have been discovered orbiting Jupiter so far! (Saturn has the most with 293, but who’s counting.) Ganymede and Io, two of Jupiter’s Galilean moons, met in the sky on October 20th, 2026. Today’s video captures the meeting, with Ganymede briefly blocking Io from view. This event, when an astronomical object passes in front of another and either completely or partially blocks it, is called a mutual occultation. The mutual occultations of Galilean moons are rare to witness because they require Earth’s edge-on view of their orbits. This occurs once every 6 years when Jupiter reaches its equinox and appears less “tilted”. Ganymede is also casting its shadow on Jupiter’s right side. Any fictional Jovian species within the shadow would experience a solar eclipse! post sent by @TheFeedReaderBot - tfrbot.com

Sometimes it's night on the ground but day in the air. As the Earth rotates to eclipse the Sun, sunset rises upfrom the ground. Therefore, at sunset on the ground, sunlight still shines on clouds above. Under usual circumstances, a pretty sunset might be visible, but unusual noctilucent clouds float so high up they can be seen well after dark. Normally too dim to be seen, they may become visible just after sunset during the summer when illuminated by sunlight from below the horizon. Noctilucent clouds are the highest clouds and are known more technically as polar mesospheric clouds. Featured here as they appeared in early August, a network of blue noctilucent clouds was captured in the distant sky above a field of green grass near Linköping, Sweden, with trees in stark silhouette across the horizon. Much about noctilucent clouds has been discovered only in the past two decades, while how they form and evolve remains a topic of active research. post sent by @TheFeedReaderBot - tfrbot.com