The DART mission, or NASA’s Double Asteroid Redirection Test, will lift off at 10:20 p.m. PT on Nov. 23 aboard a SpaceX Falcon 9 rocket from Vandenberg Space Force Base in California.
After launching in November, NASA will test its asteroid deflection technology in September 2022 to see how it affects the motion of a near-Earth asteroid in space.
The target of this asteroid deflection technique is Dimorphos, a small moon orbiting the near-Earth asteroid Didymos. This will be the agency’s first full-scale demonstration of this type of technology on behalf of Planetary Defense.
Near-Earth objects are asteroids and comets whose orbits place them within 30 million miles of Earth. Threat detection of near-Earth objects, or NEOs, which can potentially cause serious damage, is a primary focus of NASA and other space organizations around the world.
Didymos and Dimorphos
Two decades ago, a binary system consisting of a near-Earth asteroid was found orbiting a moon called Didymos. In Greek, Didymos means “twin”, which was used to describe how the larger asteroid, which is about half a mile across, is orbited by a smaller moon whose diameter is 525 feet. At the time, the moon was known as Didymos B.
Clemenis Cygnis, a planetary scientist at Aristotle University in Thessaloniki and a member of the DART team, suggested that the moon be named Dimorphos.
“Dimorphos, meaning ‘two forms’, refers to the position of this object as the first celestial body whose ‘form’ of orbit has been significantly changed by humanity—in this case, by the Dart effect,” says Tsignis. he said. “As such, it will be the first object known to humans from two distinct forms, one seen by Dart before the impact and the second by the European Space Agency’s HERA a few years later.”
In September 2022, Didymos and Dimorphos will be relatively close to Earth and within 6,835,083 miles (11 million kilometers) of our planet. This is the right time for the dart mission to happen.
According to NASA, DART will intentionally crash into Dimorphos to alter the motion of the asteroid in space. This collision will be recorded by LICIACube, a companion CubeSat or Cube satellite provided by the Italian Space Agency. The CubeSat will travel on Dart and then be deployed before impact to record what happens.
“Astronomers will be able to compare observations from Earth-based telescopes before and after Dart’s kinetic impact to determine how much the orbital period of Dimorphos changed,” Tom Statler, DART program scientist at NASA Headquarters, said in a statement. Has been.” “That’s the key measurement that will tell us how the asteroid responded to our deflection effort.”
A few years after impact, the European Space Agency’s HERA mission will conduct follow-up investigations of Didymos and Dimorphos.
While the DART mission was developed for the NASA Planetary Defense Coordination Office and managed by the Johns Hopkins University Applied Physics Laboratory, the mission team will work with the HERA mission team as part of an international collaboration called Asteroid Impact and Deflection Assessment, or known as AIDA.
“DART is the first step in methods for testing dangerous asteroid deflections,” Andrea Riley, DART program executive at NASA Headquarters, said in a statement. “Potentially hazardous asteroids are a global concern, and we are excited to work with our Italian and European partners to collect the most accurate data possible from this kinetic impact deflection demonstration.”
a first mission
Dimorphos was chosen for this mission because of its size relative to asteroids that could pose a threat to Earth.
The DART would crash into Dimorphos while traveling at 14,763.8 mph. A camera on DART, called DRACO, and autonomous navigation software will help the spacecraft locate and collide with dimorphos.
This accelerating effect would only change the speed of Dimorphos as it orbits Didymos by up to 1%, which doesn’t sound like much – but it would change the Moon’s orbital period by several minutes. That change can be observed and measured on Earth with telescopes on the ground. According to the European Space Agency, this will be the first time humans have changed the dynamics of a Solar System body in a measurable way.
Three years after the impact, Hera will arrive to study Dimorphos in detail, measure the Moon’s physical properties, study the Dart impact, and study its orbit.
It may seem like a long time to wait between impact and follow-up, but it is based on lessons learned in the past.
In July 2005, NASA’s Deep Impact spacecraft launched an 815-pound copper impactor into a comet, Tempel 1. But the spacecraft was not able to see the crater, which resulted in tons of dust and ice from the impact. However, in 2011 NASA’s Stardust mission was able to characterize the impact—a 492-foot gash.
Together, the valuable data collected by Dart and Hero will contribute to planetary defense strategies, in particular understanding what types of force are needed to shift the orbit of a near-Earth asteroid that collided with our planet. .
This article updates a story first published in June 2020.
Credit : www.cnn.com