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The Deep Space Network, NASA's international collection of giant radio antennas used to communicate with spacecraft at the Moon and beyond, helps scientists and engineers use gravity and radio science experiments to learn more about our planetary neighborhood. After reaching a spacecraft reaches its destination, it uses radio antennas to communicate with the Deep Space Network, which in turn transmits radio signals back to the spacecraft. Every spacecraft travels in a predetermined path emitting radio signals as it orbits around its target. Scientists and engineers can infer the spacecraft's location and how fast it's going by measuring changes in the spacecraft's radio signal frequency. This is made possible by the Doppler effect, the same phenomenon that causes a siren to sound different as it travels towards and away from you. The Doppler phenomenon is observed here when the spacecraft and the Deep Space Network antenna move in relation to each other. Differences between the frequency of radio signals sent by the spacecraft as it orbits and signals received on Earth give us details about the gravitational field of a planetary body. For example, if the gravity is slightly stronger, the spacecraft will accelerate slightly more. If gravity is slightly weaker, the spacecraft will accelerate slightly less. By developing a model of the planetary body's gravitational field, which can be mapped as a gravitational shape, scientists and researchers can deduce information about its internal structure. The Deep Space Network was developed by and is managed by NASA's Jet Propulsion Laboratory (JPL) in Southern California. The antennas of the Deep Space Network are the indispensable link to robotic explorers venturing beyond Earth. They provide the crucial connection for commanding our spacecraft and receiving never-before-seen images and scientific information on Earth, propelling our understanding of the universe, our solar system and ultimately, our place within it. JPL manages the Deep Space Network for the Space Communications and Navigation (SCaN) Program, based at NASA Headquarters within the Space Operations Mission Directorate. Learn more about the DSN at go.nasa.gov/about-dsn

This movie captures the breakup of the asteroid Dimorphos when it was deliberately hit by NASA's 1,200-pound Double Asteroid Redirection Test (DART) mission spacecraft on September 26, 2022. The Hubble Space Telescope had a ringside view of the space demolition derby. The Hubble movie starts at 1.3 hours before impact. The first post-impact snapshot is 2 hours after the event. Debris flies away from the asteroid in straight lines, moving faster than four miles per hour (fast enough to escape the asteroid's gravitation pull, so it does not fall back onto the asteroid). The ejecta forms a largely hollow cone with long, stringy filaments. At about 17 hours after the impact the debris pattern entered a second stage. The dynamic interaction within the binary system started to distort the cone shape of the ejecta pattern. The most prominent structures are rotating, pinwheel-shaped features. The pinwheel is tied to the gravitational pull of the companion asteroid, Didymos. Hubble next captures the debris being swept back into a comet-like tail by the pressure of sunlight on the tiny dust particles. This stretches out into a debris train where the lightest particles travel the fastest and farthest from the asteroid. The mystery is compounded later when Hubble records the tail splitting in two for a few days. Credits Science: NASA, ESA, STScI, Jian-Yang Li (PSI)