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NASA’s Carruthers Geocorona Observatory Reveals ‘First Light’ Images NASA’s Carruthers Geocorona Observatory has captured its first images from space, revealing rare views of Earth and the Moon in ultraviolet light. Taken on Nov. 17 — still months before the mission’s science phase begins — these “first light” images confirm the spacecraft is healthy while hinting at the incredible views to come.

The initial images consist of two from Carruthers’ Wide Field Imager and two from its Narrow Field Imager. Each imager captured two different views: one showing a broad spectrum of far ultraviolet light, and one revealing light from Earth’s geocorona.

Comparison of wide field and narrow field images from NASA's Carruthers Geocorona Observatory: Each column shows far ultraviolet and Lyman-alpha views of Earth, with brightness color scales, using wide and narrow field imagers. These four images constitute the “first light” for the Carruthers Geocorona Observatory mission. The images were taken on Nov. 17, 2025, from a location near the Sun-Earth Lagrange point 1 by the spacecraft’s Wide Field Imager (left column) and Narrow Field Imager (right column) in far ultraviolet light (top row) and the specific wavelength of light emitted by atomic hydrogen known as Lyman-alpha (bottom row). Earth is the larger, bright circle near the middle of each image; the Moon is the smaller circle below and to the left of it. The fuzzy “halo” around Earth in the images in the bottom row is the geocorona: the ultraviolet light emitted by Earth’s exosphere, or outermost atmospheric layer. The lunar surface still shines in Lyman-alpha because its rocky surface reflects all wavelengths of sunlight — one reason it is important to compare Lyman-alpha images with the broad ultraviolet filter. The far ultraviolet light imagery from the Narrow Field Imagery also captured two background stars, whose surface temperatures must be approximately twice as hot as the our Sun’s to be so bright in this wavelength of light. NASA/Carruthers Geocorona Observatory When Carruthers captured these images, the Moon was also in its field of view and slightly closer to the spacecraft than Earth was, making the Moon appear larger and closer to Earth than usual.

The specific wavelength Carruthers observed in two of the images, called Lyman-alpha, is light emitted by atomic hydrogen. The faint glow of Lyman-alpha from hydrogen in Earth’s outer atmosphere is called the “geocorona,” Latin for “Earth crown.”

In the broad-spectrum images, the Moon and Earth look similar: both are spheres with well-defined edges. However, in the Lyman-alpha filter, the Moon still appears as a crisp, sharp sphere while Earth appears surrounded by a bright “fuzz” extending out to space. This glow is the geocorona, the primary focus of the Carruthers mission. It is the only way to “see” Earth’s outermost atmospheric layer, although the light of the geocorona has only been photographed a handful of times in history. Carruthers will be the first mission to image it repeatedly, and from far enough away to see its great extent and discover how it changes over time.

These first images also offer a rare treat: sunlight reflected off the far side of the Moon, a view impossible to capture from Earth.



Original Annotated

An interactive slider image allowing the user to swipe between two versions of an image, one with annotations and one without. The image shows a spacecraft’s view of Earth (at center) and the Moon (lower left) in ultraviolet light. The image includes a circular heatmap with a bright yellow center (Earth) fading to green and blue at the edges, showing Earth’s geocorona. A smaller bright spot appears near the bottom edge (the Moon). A vertical color bar labeled

An interactive slider image allowing the user to swipe between two versions of an image, one with annotations and one without. The image shows a spacecraft’s view of Earth (at center) and the Moon (lower left) in ultraviolet light. The image includes a circular heatmap with a bright yellow center (Earth) fading to green and blue at the edges, showing Earth’s geocorona. A smaller bright spot appears near the bottom edge (the Moon). A vertical color bar labeled OriginalAnnotated

An interactive slider image allowing the user to swipe between two versions of an image, one with annotations and one without. The image shows a spacecraft’s view of Earth (at center) and the Moon (lower left) in ultraviolet light. The image includes a circular heatmap with a bright yellow center (Earth) fading to green and blue at the edges, showing Earth’s geocorona. A smaller bright spot appears near the bottom edge (the Moon). A vertical color bar labeled An interactive slider image allowing the user to swipe between two versions of an image, one with annotations and one without. The image shows a spacecraft’s view of Earth (at center) and the Moon (lower left) in ultraviolet light. The image includes a circular heatmap with a bright yellow center (Earth) fading to green and blue at the edges, showing Earth’s geocorona. A smaller bright spot appears near the bottom edge (the Moon). A vertical color bar labeled
Original
Annotated

Carruthers Geocorona ObservatorY

A View of Earth’s Geocorona Narrow Field Imager/Lyman-alpha filter

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Image Details

This view of the Earth, Moon, and Earth’s geocorona was captured by the Carruthers Geocorona Observatory’s Narrow Field Imager on Nov. 17, 2025. Move the slider to switch between the original version and one with overlaid annotations. In the annotated version, labels for Earth, the Moon, and Earth’s geocorona are overlaid on the image. The circle around Earth represents Earth’s surface, and the arc around Earth’s middle represents the orientation of Earth’s equator. The arrow pointing up and slightly to the left from Earth represents Earth’s rotational axis. The arrow pointing out to the right from Earth represents the direction to the Sun. The color scale indicates brightness, with brighter light appearing more yellow and dimmer light appearing more blue. The ‘glow’ that extends beyond Earth’s surface and out into space is Earth’s geocorona, which is emitted by hydrogen atoms in Earth’s exosphere in a wavelength of ultraviolet light known as Lyman-alpha.

These initial images were taken with short, five-minute exposures — just long enough to confirm that the instrument is performing well. During the main science phase, Carruthers will take 30-minute exposures, allowing it to reveal even fainter details of the geocorona and trace how Earth’s outer atmosphere responds to the changing Sun.

Carruthers launched on Sept. 24 and is just a few weeks from completing its journey to the Sun-Earth Lagrange point 1, a point of gravitational balance roughly 1 million miles closer to the Sun than Earth is. Carruthers will begin its primary science phase in March 2026, when it will begin sending back a steady stream of ultraviolet portraits of our planet’s ever-shifting outer atmosphere.

By Miles Hatfield
NASA’s Goddard Space Flight Center, Greenbelt, Md.

About the Author Miles Hatfield Miles Hatfield

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Details Last Updated Dec 16, 2025 Related Terms Heliophysics Air Traffic Solutions Carruthers Geocorona Observatory (GLIDE) Goddard Space Flight Center Heliophysics Division Heliophysics Research Program Missions NASA Directorates Science & Research Science Mission Directorate

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NASA’s Carruthers Geocorona Observatory Reveals ‘First Light’ Images