The DownlinkMay 05, 2023

Moonshadow, Moonshadow

Space Snapshot

Shadowcam lunar south pole

NASA and the Korea Aerospace Research Institute have teamed up to peer into never-before-seen areas on the Moon. ShadowCam, a hypersensitive camera provided by NASA to fly on Korea’s Danuri lunar orbiter, takes high-resolution images like the one above of permanently shadowed regions of the lunar south pole. Although these areas never receive any direct sunlight, ShadowCam is sensitive enough to capture detailed images using only the tiny amount of sunlight reflected off the Earth or off nearby mountains and crater walls. The image above shows the rim of Marvin crater, in a general area of interest for future crewed missions. Image credit: NASA/KARI/ASU.

Do you want to help make sure astronauts make it to the lunar south pole? The Planetary Society is advocating for the funding needed to see the Artemis missions through. Lend your support to our space policy and advocacy program so that we can keep working to champion the scientific exploration of our Solar System and beyond.

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Fact Worth Sharing

Moon illustration

A little sunlight goes a long way. Some permanently shadowed craters on the Moon receive so little sunlight that they are colder than most of the surface of Pluto, which is about five billion kilometers (three billion miles) farther from the Sun.

Mission Briefings

Starship flight1 plume

Environmental groups are suing the FAA over the Starship launch. The lawsuit argues that the Federal Aviation Administration failed to fully assess the environmental impacts of SpaceX Starship launches from Boca Chica, TX. It cites as an example the April 20 launch that scattered debris over Boca Chica State Park, created plumes of material spreading over 10 kilometers (about 6 miles), and caused a 3.5-acre wildfire. SpaceX says it is taking measures to prevent similar debris in future launches. Pictured: Starship taking off. Image credit: SpaceX.


Voyager 2’s lifespan has been extended thanks to engineering ingenuity. The spacecraft, which launched in 1977 and is now in interstellar space, has very limited battery life remaining and was facing possible shutdown. But mission engineers found a way to reroute power to science instruments from a non-essential voltage regulator, potentially extending the spacecraft’s life by three years to 2026.


Plutonium, which powers missions like Voyager, is in short supply. Missions that travel far from the Sun need nuclear power to operate, but the particular isotope those generators use (plutonium-238) is very difficult to produce. Only about 1.5 kilograms (about 3.3 pounds) of plutonium-238 is produced in the United States each year, and this won’t be enough to power all the planetary science missions planned for the next decade. NASA has been developing more efficient power technologies, but has had to scale back those efforts due to budget cuts.

From The Planetary Society

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Of the thousands of confirmed exoplanets, a few remind us of home. Featuring astrophysicist and exoplanet researcher Dr. Moiya McTier, the newest video from The Planetary Society takes you on a tour of three Earth-like exoplanets and explains what makes them similar to our precious home world. Pictured: An artist’s impression of Kepler-186f, the first confirmed Earth-sized planet in a star’s habitable zone. Image credit: NASA/Ames/JPL-Caltech/T. Pyl.

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What happens when you combine a global pandemic, growing competition from the private sector, and a never-before-tried mission? In the case of NASA’s Psyche mission, you get a delay. When Psyche missed its launch date in 2022 it set off a chain reaction of delays and cost overruns on other missions led by the Jet Propulsion Laboratory (JPL). Laurie Leshin, who took over as JPL Director around the time this was happening, shared her insights with us about the myriad causes that contributed to the situation, and what she’s doing to right the ship.

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Marvel ain’t got nothin’ on these world-saving superheroes. Every two years the world’s planetary defense experts gather to discuss and advance their work protecting Earth from asteroid and comet impacts. In this week’s Planetary Radio, Mat Kaplan brings listeners behind the scenes at the 2023 Planetary Defense Conference in Vienna, Austria, sharing exclusive interviews with the people at the forefront of planetary defense.

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Planetary Society Vice President Heidi Hammel has received a top honor from NASA. The agency awarded Dr. Hammel an Exceptional Public Service Medal to honor her exemplary career in service to NASA and to the planetary science community. Dr. Hammel is also Vice President for Science for the Association of Universities for Research in Astronomy, and an Interdisciplinary Scientist for the James Webb Space Telescope.

What's Up

Mars illustration

Venus shines in the evening west, brighter than any nighttime star. Up higher, look for reddish Mars. In the predawn east you can find Saturn looking yellowish, with bright Jupiter starting to appear over the eastern horizon. The Eta Aquarid meteor shower peaks overnight on May 5-6, with meteors appearing to come from the constellation Aquarius. Find out what else May’s night skies have in store for you.

Wow of the Week

Ispace eclipse from moon crop

The Moon casts its shadow on Earth in this remarkable image from the Japanese ispace Hakuto-R lunar lander, taken on April 20. If you look closely at our planet you can see a circular dark patch, which from Earth’s perspective was a total solar eclipse. This is just one of our picks for April’s best space images. Image credit: ispace.

Send us your artwork!

We love to feature space artwork in the Downlink. If you create any kind of space-related art, we invite you to send it to us by replying to any Downlink email or writing to [email protected]. Please let us know in your email if you’re a Planetary Society member!