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The Double Asteroid Redirection Test successfully rerouted the asteroid Dimorphos A NASA spacecraft accidentally crashed into a space rock according to the agency, on September 26.
The DART mission, a full-scale demonstration of warping technology, was the world’s first in the name of planetary defense. The mission was also the first time that humanity had intentionally altered the motion of a celestial body in space.
Before impact, Dimorphos took 11 hours and 55 minutes to orbit its larger parent asteroid, Didymos. Astronomers used ground-based telescopes to measure how Dimorphos’ orbit changed after the impact.
Dimorphos now takes 11 hours and 23 minutes to orbit Didymos. The DART spacecraft has changed lunar asteroid 32 minutes in orbit.
At first, astronomers expected DART to be successful if it shortened the trajectory by 10 minutes.
“We all have a responsibility to protect our home planet. After all, it’s 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 that we are serious about protecting the planet. This is a turning point for planetary defense and for all of humanity, demonstrating the commitment of NASA’s exceptional team and its partners around the world.”
According to the DART team, neither Dimorphos nor Didymos poses a threat to Earth, but the binary asteroid system was a perfect target for testing warp technology.
“For the first time, humanity has changed the orbit of a planetary object,” said Laurie Glaze, director of NASA’s Planetary Science Division.
“As new data comes in every day, astronomers will be able to better assess whether and how a mission like DART could be used to protect Earth from an asteroid collision in the future. ”
The DART team continues to collect data by observing the double asteroid system, and the orbital measurement may become more accurate in the future. Currently, there is an uncertainty of plus or two minutes.
A new image of Dimorphos, taken by the Hubble Space Telescope, shows the debris trail splitting in two at its comet-like tail. Scientists are still working to understand the significance of fragmentation.
The team is now focusing on measuring how much impulse is transferred from DART to Dimorphos. At the time of impact, the spacecraft was traveling at approximately 14,000 miles per hour (22,530 kilometers per hour). Astronomers will analyze the amount of rock and dust thrown into space after the impact.
The DART team believes that the recoil from the plume “significantly enhanced” the spacecraft’s thrust against the asteroid, unlike the release of air from a balloon, according to NASA.
“While we’ve done more to the system than just change the orbit, we’ve left Dimorphos in a bit of a wobbly state,” said Tom Statler, NASA’s DART program scientist. “So over time, there can be some interaction between the wobble and the orbit, and things will work out. But surely it will never return to the old 11 hour 55 minute orbit.
Astronomers are still studying the surface of Dimorphos and how faint or strong it is. The DART team’s first look at Dimorphos, delivered by DART before the crash, shows that the asteroid is a pile of debris held together by gravity.
Images continue to come back from the Lightweight Italian CubeSat, or LICIACube, a minisatellite launched by the Italian Space Agency to image asteroids. A robot photojournalist on a DART mission.
In about four years, the European Space Agency’s Hera mission will also fly by the double asteroid system to study the impact crater and measure the mass of Dimorphos.
“DART has given us some interesting information about both asteroid properties and the effectiveness of a kinetic impactor as a planetary defense technology,” said Nancy Chabot, DART coordinator at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland. “The DART team continues to work on this rich data set to fully understand this first planetary defense test of asteroid deflection.”
The research team chose Dimorphos for this mission because its size is comparable to asteroids that could pose a threat to Earth. An asteroid the size of Dimorphos could cause “regional devastation” if it collided with Earth.
Near-Earth objects are asteroids and comets with orbits that place them within 30 million miles (48.3 million kilometers) of Earth. Detecting the threat of near-Earth objects that can cause serious damage is a major focus of NASA and other space agencies around the world.
No asteroids are currently on a direct collision course with Earth, but there are over 27,000 near-Earth asteroids of all shapes and sizes.
Finding and measuring populations of hazardous asteroids are priorities for NASA and its international partners. It is called the design of a space-based telescope Near Earth Object Surveyor mission currently under review.
“We shouldn’t be too eager to say that one test on one asteroid tells us exactly how every other asteroid would behave in a similar situation,” Statler said. “But what we can do is use this test as a reference point for our physics calculations in our simulations of how different types of impacts should behave in different situations.”
