ALT This natural color view of Ganymede was taken from the Galileo spacecraft during its first encounter with the satellite. The dark areas are the older, more heavily cratered regions and the light areas are younger, tectonically deformed regions. The brownish-gray color is due to mixtures of rocky materials and ice. Bright spots are geologically recent impact craters and their ejecta. The finest details that can be discerned in this picture are about 8 miles (13.4 kilometers) across. Credit: NASA/JPL

ALT An approximately true color/contrast mosaic of Ganymede images pj34_01 and pj34_02. The viewing geometry for image pj34_02 was used for the mosaic. The color is mainly based on Ganymede's global visible light spectrum but it is somewhat subjective and approximate. Credit: NASA / JPL-Caltech / SwRI / MSSS / Björn Jónsson

ALT An area west of Jezero Crater, Mars, as captured by the HiRISE instrument aboard NASA's Mars Reconnaissance Orbiter on June 13, 2026. The terrain consists of a desert landscape with small hills and fields of dunes. The car-sized Perseverance rover is visible as a small, bright, blue-green dot, circled in yellow. The rover's tracks are also visible as a thin gray line winding through the terrain. NASA/JPL-Caltech/UArizona

ALT A three panel image. First, an astronaut photograph showing an object as it breaks up in Earth’s atmosphere. Against the blackness of space, the object appears like a bright white dot of light with a small tail to its right. Second, an astronaut photograph of the object breaking up, taken about half a minute after the first photo. The object looks like a bright white plus sign with a long tail. The tail is whiter closer to the object and orange at its opposite end. Third, an astronaut photograph of the object breaking up, taken about a minute after the first photo. The object is a long streak of white and orange. There are multiple smaller streaks indicating different pieces of the object. Credit: NASA

ALT An artist's concept shows a planet at the top center with a blue band arcing around it in a horseshoe shape. The blue band is labeled the magnetosheath. The inner part of this blue band, closest to the planet, is labeled the magnetopause. The outer edge of the blue band is labeled the bow shock. Just outside the blue band, to the lower left of it, is a purple wedge-shaped area labeled the foreshock. On the far left is a red shaded area with red arrows pointing from left to right, appearing to push against the magnetosheath (blue region) and foreshock (purple) region, labeled the stellar wind.

ALT Venus is seen next to the crescent Moon, before the start of occultation, on Wednesday, June 17, 2026, from the Mary W. Jackson NASA Headquarters building in Washington. The Moon occulted, or passed in front of, Venus for the first of three time this year. Photo Credit: (NASA/Joel Kowsky)

ALT A technician wearing white clean room protective attire installing Nancy Grace Roman Space Telescope's solar array Sun shield — a set of solar panels on the telescope. The panels are dark with red outlines. Credit: NASA

ALT Illustrated graphic showing a portion of Earth, with major land masses appearing gold-brown and blue-green. The text "Join Us! Register September 19, 2026" is centered. At upper left, a simple representation of a waxing gibbous Moon with the words “Observe the Moon” is shown inside of a location pin.

ALT A person in a head-to-toe white clean room suit holds a large purple "boarding pass" for NASA's Nancy Grace Roman Space Telescope in Goddard's large cleanroom. The boarding pass includes an image of the 18 detectors, an artist concept image of the telescope, a QR code, and the NASA logo. "Roman Telescope" is written where the name would go.

ALT The plate attached to the Roman telescope, where a memory card containing names will be attached. It's a tall, thin, rectangular silver plate. At the top of the plate is the stylized Nancy Grace Roman name logo. Below is the silhouette of Roman's 18-square detectors in their iconic arch shape. Text below that reads "NASA's first chief astronomer, Nancy Grace Roman, persevered through barriers and made powerful space telescopes a reality. She envisioned a world where everyone had access to, and enthusiasm for, science. This observatory is the continuation of her legacy and dream." Below the text is an illustration of Dr. Roman looking up, next to her name and the years 1925-2018. Below the years is a small box where the memory card will be affixed. The plate is held down with two large bolts at the top and bottom.

ALT The fully assembled Roman telescope in the clean room, standing upright. It's a silver cylinder with solar panels peeking out from behind both sides like wings. The hood is deployed, like a black sun visor on a baseball cap. Orange lifts and people in white cleanroom suits surrounded the telescope, highlighting how large it is. The unfolded lifts only reach about one-quarter of the way up the telescope's body. Instrumentation and cables are visible in a section about one-third of the way up the body. Thousands of tiny squares on the wall behind the telescope are air filters for the clean room.

ALT Four people with backpacks pause to examine rocks on a hillside under a clear blue sky, with a large orange and tan boulder in the foreground. Credit: NASA

ALT This photo of the Moon was captured by the Artemis II crew aboard the Orion spacecraft a few hours before the lunar flyby on April 6, 2026. During the flyby, the crew captured critical science observations as they traveled around the far side of the Moon, traveling farther than any humans ever before. The Moon resembles a gray cratered orb in the distance, standing out against the blackness of space. Credit: NASA

ALT The Moon appears half-illuminated in this photo captured by the Artemis II crew on April 6, 2026. The terminator — the difference between light and darkness — provides a stark contrast and even greater perspective of the Moon's rocky, uneven, and otherworldly surface features. The near side of the Moon, which is what we can see from Earth, appears in the dark gray regions at the top of this image. The Moon stands out against the blackness of space around it. Credit: NASA

ALT The Artemis II crew was tasked with capturing many key features visible in this image of the Moon, captured on April 6, 2026. The terminator, or the difference in light and darkness, is visible on the top left. The large dark gray area toward center-left is Orientale Basin, while the characteristic dark patches of ancient lava flow we see on the near side are visible on the right half of this image. The Moon stands out against the blackness of space around it. Credit: NASA

ALT This photo of a crescent Moon and crescent Earth was taken by an Artemis II astronaut during their lunar flyby on April 6, 2026. This image captures one of the final moments before their loss of signal with Earth as the Orion spacecraft flew around the far side of the Moon, reemerging and regaining contact approximately 40 minutes later. Earth can be seen peeking behind the Moon in the distance. The illuminated regions of the Moon and Earth stand out against the blackness of space, while the rest are swallowed in shadow. Credit: NASA

ALT A view of Earth through a spacecraft window, showing the blue-and-white planet partially framed by the dark interior structure, cables, and hardware inside the spacecraft.