Last Monday, September 26, 2022, NASA’s DART space probe (Double Asteroid Redirection Testfor its acronym in English) intentionally crashed into Dimorphosthe small moon of the Didymo asteroid system, in what was the first planetary defense test involving a spacecraft impact to modify an asteroid’s orbit.
Two days following the impact, astronomers Teddy Kareta (of the Lowell Observatory) and Matthew Knight of the United States Naval Academy) used the Southern Astrophysical Research Telescope (SOAR)of Cerro Tololo Observatory in Chile, to capture an extensive column of dust and debris thrown from the asteroid’s surface and pushed by radiation in a similar way to what happens with the tail of a comet. In this new image, the dust tail can be seen extending from the center to the right edge of the field of view which in SOAR corresponds to regarding 3.1 arcminutes, using the Goodman High Performance Spectrograph. At the time this observation was made, that corresponds to at least 10,000 kilometers (6,000 miles) from the point of impact.
“It’s impressive how clearly we were able to capture the structure and extent of the followingmath in the days following impact.Kareta said.
“Now begins the next phase of work for the DART team analyzing the data and observations with the help of other observers around the world who were able to study this extraordinary event together.Knight added. “We plan to use SOAR to monitor material ejection in the coming weeks and months. The combination of SOAR and AEON [2] is just what we need for efficient tracking of evolving events like this”.
These observations will allow scientists to gain insight into the nature of Dimorphos’s surface, how much material was ejected by the collision, how fast it was ejected, and the particle size distribution in the expanding dust cloud – that is, whether the impact with the moon caused the ejection of large chunks of material or mainly fine dust. Analysis of this information will help scientists better protect Earth and its inhabitants by understanding the amount and nature of material resulting from an impact such as this one and how it can change the asteroid’s orbit.
SOAR telescope observations demonstrate the capabilities of NSF-funded AURA facilities in planetary defense plans and initiatives. In the future, the Vera C. Rubin Observatoryfunded by NSF and the US Department of Energy, and currently under construction in Chile, will conduct a survey of the Solar System to search for objects that are a potential threat to Earth.
Didymos was discovered in 1996 with the University of Arizona Spacewatch 0.9 meter telescope which is located in the Kitt Peak National Observatoryan NSF program from NOIRLab.
