Taking pictures in space ain’t just point and shoot. When a spacecraft is billions of miles from home, it takes an awful lot of data processing and signal gathering to turn its whispered transmissions into the kind of head-spinning, eye-popping photographs we’ve gotten used to over the decades. That’s why it’s a good thing we’ve got NASA’s Deep Space Network (DSN), a global array of antennas that just last month celebrated 50 years on the job.
Ever since Dec. 24, 1963, when the DSN went online, it’s been the call center for spacecraft sending data and pictures home from every planet in the solar system, from comets and asteroids and the sun, from Voyager 1, which is the first spacecraft to leave the solar system. The DSN is also what connected us to the Apollo astronauts and the TV cameras they carried as they orbited and walked on the surface of the moon.
“When we started building the system, in 1958, there was just a single antenna at Goldstone in California,” says DSN project manager Al Bhanji, of NASA’s Jet Propulsion Laboratory in Pasadena. “Now we have three 70-meter [230 ft.] antennas and nine 34-meter [112 ft.] antennas around the world. We’re currently handling more than 30 deep-space spacecraft from both the U.S. and other countries. That’s the greatest number at a single time in the DSN’s history.”
All those antennas live in surprisingly few places. On a rotating planet, a single fixed antenna would never be able to remain in constant communication with a deep-space ship. But three sets of antennas—placed about 120 degrees apart at selected spots on the 360-degree globe—can do the job just fine. For the DSN, those spots are Goldstone, Madrid and Canberra, Australia.
Not every spacecraft using the DSN communicates with it in quite the same way, because while technology moves fast—with constant upgrades in communications and data-processing capabilities—spacecraft may take a long, long time to get where they’re going. The New Horizons spacecraft—which will become the first ship to reconnoiter Pluto and its large moon Charon when it flies by them in July of 2015—was launched in 2006. Voyager 1 left home on Sept. 5, 1977. NASA’s tech capabilities have changed more than a wee bit since then.
For that reason, the DSN, even when it’s upgraded, must retain the ability to talk to any active spacecraft of any generation—a little like holding onto your first generation iMac to connect to a first-generation website on a first-generation Internet. “We’re using very old equipment to stay in contact with the Voyagers,” says Bhanji. “The rate of communication is slower than a 1980s modem.” By contrast, the Curiosity rover, which landed on Mars in 2012, has the most advanced on-board technology of any of the ships in the DSN fleet and thus communicates with the fastest and best parts of the network.
But slow science or fast science—data that arrives in a trickle or in a firehose blast—is ultimately the same, since it all adds to humanity’s growing understanding of the cosmos. And what of our growing appreciation of the jaw-dropping beauty of that cosmos? As the gallery of images above shows, the DSN has more than made its contribution to that mission too.