Didymos is a binary asteroid system: a pair of innocent, lumpy rocks minding their very own enterprise. Individually the 2 rocks are referred to as Didymos and Dimorphos.
NASA’s Double Asteroid Redirection Take a look at (DART) mission deliberately crashed a spacecraft into Dimorphos — the smaller asteroid within the binary system — on Sept. 26, 2022, at 7:14 p.m. EDT (2314 GMT).
The collision was designed to vary the moonlet’s orbital velocity by a fraction of a % in response to NASA (opens in new tab) in a bid to reveal a technique of deflecting an asteroid for planetary protection utilizing the “kinetic impactor” approach. Whereas Didymos isn’t a menace to Earth, this technology might defend Earth from different area rocks which may be extra harmful.
Associated: NASA’s DART asteroid-impact mission defined in footage
What’s Didymos?
These 14 radar photos present the near-Earth asteroid Didymos (65803) and its moonlet as seen by the Arecibo Observatory radio telescope in Puerto Rico in November 2003. (Picture credit score: NASA) (opens in new tab)
The pair of asteroids collectively are referred to as Didymos, however individually the 2 rocks are Didymos and Dimorphos. Didymos is a big asteroid round half a mile (2,560 toes or 780 meters) in size, whereas Dimorphos measures a mere 525 toes (160 m), in response to the Johns Hopkins College Utilized Physics Laboratory (opens in new tab) (JHUAPL), the place the DART mission relies. In some earlier protection from Area.com, Dimorphos has been known as Didymos’ moonlet or as “Didymoon.”
As the 2 asteroids orbit the solar, Dimorphos additionally orbits Didymos, circling its bigger twin each 11 hours and 55 minutes.
For many years, telescopes on Earth like Arecibo Observatory and Lowell Discovery Telescope have been in a position to observe that motion “similar to clockwork,” mentioned planetary scientist Nancy Chabot of JHUAPL throughout a press convention held earlier than DART’s launch. As Dimorphos passes between Didymos and Earth, telescopes across the globe can measure the ensuing change in brightness from the system.
Why did NASA wish to crash into Dimorphos?
The clockwork movement of the Didymos system made it very best for the DART mission, an illustration of NASA’s means to redirect harmful asteroids off collision programs with Earth. Didymos itself poses no menace to our planet however served as a check goal.
Researchers on Earth had been in a position to observe the impact of the DART spacecraft hurtling head-on into Dimorphos, the smaller asteroid. In accordance with Chabot, after the influence, the scientists anticipated to see Dimorphos full a loop of Didymos some 10 minutes sooner than its historic schedule.
DART additionally carried a cubesat known as LICIACube to movie the bigger spacecraft’s influence and beam the footage again to researchers on Earth.
On the time of DART’s influence, Didymos was seen sufficient to be a superb candidate for research and distant sufficient to be no hazard, at roughly 6.8 million miles (11 kilometers) away from Earth.
What else will we learn about Didymos?
The final picture Earth obtained from the DART spacecraft on Sept. 26, 2022, displaying the floor of Dimorphos. (Picture credit score: NASA/JHUAPL) (opens in new tab)
Didymos is without doubt one of the Amor group of asteroids, near-Earth asteroids named after asteroid 1221 Amor. These asteroids orbit the solar largely between the orbits of Earth and Mars. Didymos specifically takes a little bit over two years to finish an elliptical orbit across the solar, in response to NASA’s in-depth web page on Didymos.
The bigger asteroid of Didymos in all probability has a rocky floor coated in boulders, though NASA wrote that it doubtless lacks the regolith, or wonderful mud, that covers Earth’s moon and different asteroids. It additionally lacks any ambiance, rings or magnetosphere.
Photos taken by DART because the spacecraft sped towards its finish present a discipline of grey crags, boulders and pebbles.
Extra sources
You possibly can view photos from the JHUAPL DART mission on the mission picture gallery (opens in new tab)Alternatively, be taught extra about planetary protection with ESA (opens in new tab).
Bibliography
Mission overview. DART. Retrieved September 27, 2022, from https://dart.jhuapl.edu/Mission/index.php
NASA. In depth. NASA. Retrieved September 27, 2022, from https://solarsystem.nasa.gov/asteroids-comets-and-meteors/asteroids/didymos/in-depth/
NASA. Dart within the information. NASA. Retrieved September 27, 2022, from https://www.nasa.gov/planetarydefense/dart/dart-news
