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A Stowaway Mission to the Moon

NASA's LCROSS lunar impactor mission comes in on time and on budget

3 min read

Several months from now, the empty upper stage of an Atlas V rocket will slam into a shadowy crater near the north pole of the moon, tossing a plume of debris up into the sunlight. By then, the Atlas V will have delivered its main payload, the Lunar Reconnaissance Orbiter (LRO), and a smaller stowaway. That stowaway satellite will watch the spectacle unfold from above, looking for telltale signs that there’s water in the lunar soil, before it, too, crashes into the moon.

NASA’s current plan for manned exploration calls for establishing a base near a lunar pole, where indirect evidence suggests that frozen water is trapped in permanent darkness. Scheduled to launch in late April, the Lunar CRater Observation and Sensing Satellite mission, or LCROSS, aims to explore the nature of lunar water and determine whether it’s concentrated in small pockets or spread diffusely throughout the shadowed regions. Although these findings will help guide the strategy of lunar exploration, LCROSS is not a typical NASA mission—it wasn’t even on the drawing board three years ago.

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Two men fix metal rods to a gold-foiled satellite component in a warehouse/clean room environment

Technicians at Northrop Grumman Aerospace Systems facilities in Redondo Beach, Calif., work on a mockup of the JWST spacecraft bus—home of the observatory’s power, flight, data, and communications systems.


For a deep dive into the engineering behind the James Webb Space Telescope, see our collection of posts here.

When the James Webb Space Telescope (JWST) reveals its first images on 12 July, they will be the by-product of carefully crafted mirrors and scientific instruments. But all of its data-collecting prowess would be moot without the spacecraft’s communications subsystem.

The Webb’s comms aren’t flashy. Rather, the data and communication systems are designed to be incredibly, unquestionably dependable and reliable. And while some aspects of them are relatively new—it’s the first mission to use Ka-band frequencies for such high data rates so far from Earth, for example—above all else, JWST’s comms provide the foundation upon which JWST’s scientific endeavors sit.

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