The DownlinkJul 28, 2023

Aquatic equivalencies

Space Snapshot

Venus akatsuki

The atmosphere that shrouds Venus is paradoxical. Its extreme density creates a deadly environment at the planet’s surface, but higher up it may be home to potential signs of life — signs that are hotly contested and debated today. The question of whether there is, was, or could be life on Venus all comes down to that beautiful, enigmatic atmosphere.

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Fact Worth Sharing

Venus illustration

Venus’ atmosphere is extremely thick, creating a huge amount of pressure at the surface. If you were standing on Venus, you’d be under so much atmospheric pressure that it would feel the same as being a kilometer underwater on Earth.

Mission Briefings

Pds 70 artists impression

JWST has found water near the center of a planet-forming disk. The origin of Earth’s water is still unknown, but new insights from the powerful space telescope may shed light on the mystery. New measurements by JWST’s Mid-Infrared Instrument have detected water vapor in a protoplanetary disk, specifically in a region where rocky, terrestrial planets may be forming. This could suggest that planets like Earth form with water present from the beginning, instead of having to be seeded with water later in their planetary lives. Pictured: An artist’s impression of protoplanetary disk PDS 70. Image credit: NASA, ESA, CSA, J. Olmsted (STScI).


Chandrayaan-3’s journey to the Moon is going well so far. India's Moon rover mission has successfully raised its orbit around Earth through a series of maneuvers, which will get it to the speed and altitude needed to reach the Moon. The rover is expected to attempt a landing on the Moon on Aug. 23 or Aug. 24, where it will operate for up to 14 days.


Artemis II just finished its first launch dress rehearsal. The launch team successfully completed a practice countdown, ensuring that all launch systems are working correctly and identifying any issues well ahead of the actual launch. NASA still expects the launch to take place as planned, no earlier than November 2024. The Artemis II mission will carry four astronauts around the Moon and back.

From The Planetary Society

Enceladus plumes cassini
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The waters of Enceladus are a tantalizing place in the search for life. Phosphorus, a key ingredient for life on Earth, has been found in the subsurface oceans of Saturn's icy moon — the first time phosphorus has been found in an ocean beyond Earth. Chris Glein, a lead scientist involved with the detection, joined this week’s Planetary Radio to talk about the discovery and its implications for the search for life. Pictured: The Cassini spacecraft’s views of huge water plumes erupting from Enceladus’ south pole. Image credit: NASA/JPL.

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Why are there often no stars in photos from space? A common question we hear is why so many space images don’t show a background detail you’d expect to see: stars. The reason has to do with camera settings that will be familiar to anyone who’s ever used a camera with manual settings. Learn more in our latest video.

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Planetary defense needs your help! To defend our planet from asteroid impacts we have to ensure we find and track as many as possible. That’s where you come in. Make a gift today to support teams of astronomers who are searching the skies for potentially dangerous asteroids. Your contribution will go directly to funding their work, helping ensure we never get caught off guard by an impending impact.

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Want to make your own impact on the future of space? Join the Day of Action. Our annual advocacy event brings members together in Washington, D.C., to advocate for space. If you live in the United States, join us on Sept. 17 and 18, 2023, to meet with your representatives in Congress and speak up for the future of space science and exploration. Learn more and register today.

What's Up

Jupiter illustration

Venus is shining super bright in the western evening sky, but getting lower and lower to the horizon. Mars shines much dimmer higher in the sky, looking reddish. Saturn rises in the late evening, with Jupiter following a couple of hours later. Learn more at

Wow of the Week

Esa astronauts diving

Water on Earth helps frame our exploration of space, from helping us know where to look for life on other worlds to contextualizing conditions on the surface of Venus. It also helps astronauts prepare to operate in microgravity. At the European Space Agency, a new class of astronaut candidates is learning to SCUBA dive — a typical step in the astronaut training process.

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!