How New Horizons “talks” to Earth

A signal that took 265 minutes to travel from NASA’s New Horizons probe shows that it survived a close encounter with Pluto, and can now begin transmitting images and data back to Earth – a 16-month process
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High-gain antenna: Primary dish with 0.3° wide beam requires probe to be pointing directly at Earth in order for NASA to receive signal

5 billion km to Earth 8-12 GHz frequency

Medium-gain antenna: Secondary dish with wider, 4° beam. Used as backup when probe not pointing directly at Earth

Seven instruments collect mass of data on geology and atmosphere of Pluto and its five moons

Data sent to solid-state memory banks 8GB

Processor compresses and reformats data files CPU

New files put in flash memory and transmitted
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NASA’S DEEP SPACE NETWORK (DSN)

Earth rotation

Goldstone California

Johannesburg South Africa Closed in 1974 for political reasons, and moved to Spain

Madrid Spain

Canberra Australia

DSN: Three sites – spaced out approximately 120° apart longitudinally around world – keep in constant contact with spacecraft as Earth rotates.
Before New Horizons sinks below horizon at one DSN site, another one picks up signal
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Sources: Gizmodo, NASA, wire agencies

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