Robotic space probes have been venturing into the depths of the Solar System since the 1960s. The Deep Space Network (DSN) makes it possible to communicate with such craft. There are three facilities across the Earth: (1) Goldstone, California; (2) Canberra, Australia and (3) Madrid, Spain. The DSN has a proud history and has made it possible for us to visit every planet in our little cosmic neighbourhood.
In the late 1950s, the Jet Propulsion Laboratory (JPL) had perfected microtracking, a technique used to follow the flight path of an object as it orbited the Earth. This paired with radio facilities was crucial because it let scientists accurately pinpoint where a rocket, or an intercontinental ballistic missile (ICBM), was in the sky at any point during a flight. This information was key to mission success because, for example, it let technicians know when to adjust a rocket’s course.
While JPL developed microtracking, the United States Department of Defence was working on an idea that linked communication ground stations across the planet. Envisioned as the World Net, JPL was intrigued and the two began creating the DSN’s predecessor together.
By creating three networked communication facilities 120 degrees apart on the Earth’s surface, it was possible to keep in contact with spacecraft (and ICBMs) 24/7 while the planet rotated.
In early 1958, the first World Net 26-metre-wide dish, Deep Space Instrument Facility 11 (DSIF-11), was set up on the Goldstone Dry Lake in the Mojave Desert. America’s first successful satellite, Explorer 1, relied heavily on the tracking facility when it went to space on February 1, 1958.
A few months after Explorer 1’s flight, NASA was formed and all space-related projects operated by America’s Navy, Army and Airforce were placed under the one government agency. This included JPL and scientists quickly realised that one network could be used to monitor all space missions.
A second World Net antenna (DSIF-41) followed in Woomera, South Australia, and a third (DSIF-51) in Hartebeesthoek, South Africa. The construction of both was completed by late 1960.
Just as NASA was gearing up for the Apollo Program, JPL Director William Pickering formally established the Deep Space Network on December 24, 1963. The World Net was adequate but there were a lot of NASA facilities involved in its operation making it overly complicated. With more sophisticated space missions about to begin, the decision streamlined effectiveness.
By this time, the DSN consisted of the three facilities—Goldstone, Woomera and Hartebeesthoek—and a control centre at JPL’s headquarters in Pasadena, California.
The Goldstone complex was the first to be upgraded with the installation of a 64-metre dish, the design being very similar to the hugely successful radio telescope in Parkes, NSW. The new dish was more powerful and had a greater signal-to-noise ratio, meaning a spacecraft could be heard easier compared to background noise interference.
Cosmic microwave background noise is a remnant left over from the Big Bang and can be heard as static on radio frequencies throughout the Universe.
Instead of upgrades for Woomera and Hartebeesthoek, new facilities were constructed in Tidbinbilla, near Canberra, and Madrid, Spain. The Woomera site was closed in 1972 to save money and the South African complex was shut down in 1974. The South African facility ended for diplomatic reasons because of the civil unrest the country was experiencing at the time.
On March 19, 1965, the new Australian site was officially opened and christened the Canberra Deep Space Communication Complex (CDSCC). As of 2022, the site has one 70-metre and three 34-metre dishes.
The DSN has been involved in some of the most important missions of all time, such as in 1965 when the first close up pictures of another planet were taken (Mariner 4 at Mars); the crewed Apollo flights to the Moon; the two Voyagers’ grand tour of Jupiter, Saturn, Uranus and Neptune; Galileo and Juno’s exploration of Jupiter and its moons; Cassini–Huygens’s long-term investigation of the Saturnian system and New Horizon’s flyby of Pluto.
More recently, the DSN played a critical role when the Perseverance rover landed on Mars and OSIRIS-Rex’s sample collection of the asteroid Bennu.
In the 1980s, the DSN’s three 64-metre dishes were increased to 70 metres. This greatly increased their capabilities but was pushing communication limits of the time. The upgrades were crucial for data collection during Voyager 1 and 2’s encounters of the outer planets, which forever changed our understanding of the gas and ice giants.
Currently, the DSN is monitoring nearly 40 spacecraft and another 30 missions are expected to be added to the workload soon, including NASA’s upcoming Artemis missions. With more pressure than ever before being applied to the network’s resources, the DSN is slowly getting upgraded again.
Besides a new 34-metre dish installed in Madrid, the CDSCC’s 70-metre dish, Deep Space Station 43, has been enhanced. After being offline for a year, the dish is now the only location in the Southern Hemisphere that can communicate with Voyager 2. The spacecraft was launched in 1977 and, as of 2018, is travelling through interstellar space.
Once the rest of the major upgrades are completed, the DSN will continue to be on the cutting edge of space communications like it has done since its inception.
Photo Credit: The New York Times (https://www.nytimes.com/2020/03/04/science/voyager-2-nasa-deep-space-network.html)
Sources:
Canberra Deep Space Communication Complex (https://www.csiro.au/en/about/facilities-collections/international-facilities/cdscc)
Deep Space Network at 50, The (https://physicstoday.scitation.org/doi/10.1063/PT.3.2619)
Deep Space Network: How NASA Spacecraft Make Long-Distance Calls, The (https://astronomy.com/news/2020/11/the-deep-space-network-how-spacecraft-make-long-distance-calls)
DSN Complexes (https://www.nasa.gov/directorates/heo/scan/services/networks/deep_space_network/complexes)
DSN Functions (https://www.nasa.gov/directorates/heo/scan/services/networks/deep_space_network/functions)
DSN History (https://www.nasa.gov/directorates/heo/scan/services/networks/deep_space_network/history)
Increasing Demands Putting Pressure on Deep Space Network (https://spacenews.com/increasing-demands-putting-pressure-on-deep-space-network/)
NASA’s Deep Space Network Looks to the Future (https://phys.org/news/2021-09-nasa-deep-space-network-future.html)
NASA’s Deep Space Network Upgraded (https://skyandtelescope.org/astronomy-news/nasas-deep-space-network-upgraded/)
What is the Deep Space Network? (https://www.nasa.gov/directorates/heo/scan/services/networks/deep_space_network/about)
Leave a Reply