Analysis of data obtained over the past two weeks by NASAs Double Asteroid Redirection Test (DART) investigation team shows the spacecraft's kinetic impact with its target asteroid, Dimorphos, successfully altered the asteroids orbit. This marks humanitys first time purposely changing the motion of a celestial object and the first full-scale demonstration of asteroid deflection technology.
All of us have a responsibility to protect our home planet. After all, its the only one we have, said NASA Administrator Bill Nelson. This mission shows that NASA is trying to be ready for whatever the universe throws at us. NASA has proven we are serious as a defender of the planet. This is a watershed moment for planetary defense and all of humanity, demonstrating commitment from NASA's exceptional team and partners from around the world.
Prior to DARTs impact, it took Dimorphos 11 hours and 55 minutes to orbit its larger parent asteroid, Didymos. Since DARTs intentional collision with Dimorphos on Sept. 26, astronomers have been using telescopes on Earth to measure how much that time has changed. Now, the investigation team has confirmed the spacecrafts impact altered Dimorphos orbit around Didymos by 32 minutes, shortening the 11 hour and 55-minute orbit to 11 hours and 23 minutes. This measurement has a margin of uncertainty of approximately plus or minus 2 minutes.
Before its encounter, NASA had defined a minimum successful orbit period change of Dimorphos as change of 73 seconds or more. This early data show DART surpassed this minimum benchmark by more than 25 times.
This result is one important step toward understanding the full effect of DARTs impact with its target asteroid said Lori Glaze, director of NASAs Planetary Science Division at NASA Headquarters in Washington. As new data come in each day, astronomers will be able to better assess whether, and how, a mission like DART could be used in the future to help protect Earth from a collision with an asteroid if we ever discover one headed our way.
The investigation team is still acquiring data with ground-based observatories around the world as well as with radar facilities at NASA Jet Propulsion Laboratorys Goldstone planetary radar in California and the National Science Foundations Green Bank Observatory in West Virginia. They are updating the period measurement with frequent observations to improve its precision.
Focus now is shifting toward measuring the efficiency of momentum transfer from DARTs roughly 14,000-mile (22,530-kilometer) per hour collision with its target. This includes further analysis of the "ejecta the many tons of asteroidal rock displaced and launched into space by the impact. The recoil from this blast of debris substantially enhanced DARTs push against Dimorphos a little like a jet of air streaming out of a balloon sends the balloon in the opposite direction.
