Headlines:
* Australia: "Tesla Sinks in Sydney Harbour after celebrating winning 'Good Design Award' (The Guardian) * Europe: "EU orders Coca-Cola to remove 'detrimental' chemical from fizzy drinks (The Telegraph) * USA: "Britney Spears is to perform at the 2023 Grammys (The New York Times) * Japan: "Japan's Prime Minister Fumio Kishida wins his party's endorsement for the leadership (The Japan Times) * Middle East: "Israel and Lebanon agree on maritime border between the two countries (Al-Jazeera) * Asia: "Tokyo Olympics raised concerns over extreme heat and humidity (The Straits Times) Please note that these news headlines are subject to change and might not be the most recent or up-to-date information. The writing style is academic and informative... and the tone is professional with an absence of adoration.
Rogue asteroids, to put it simply, pose a threat to Earth. Though there hasn't been a cataclysmic event in about 65 million years, that's not to say there haven't been nail-biting moments during space rock flybys ⁘ in 2013, for instance, the Chelyabinsk asteroid slammed into Earth's atmosphere "blazing like a second sun" and sending shockwaves through the surrounding area.
Space agencies around the world understandably want to be prepared. To this end, NASA launched the Double Asteroid Redirection Test ( DART ) spacecraft in 2022, its first mission dedicated to demonstrating asteroid deflection through kinetic impact. DART successfully collided with a near-Earth asteroid called Dimorphos, which is part of a binary system as it orbits a larger asteroid named Didymos . Lots of incredible information has been gleaned from this impact already, and we just got a little more. According to a paper published this year about the event, DART created a large crater in Dimorphos, in fact reshaping the rock so dramatically it derailed from its original progression.
"For the most part, our original pre-impact predictions about how DART would change the way Didymos and its moon move in space were correct," Derek Richardson, a professor of astronomy at the University of Maryland and a DART investigation working group lead, said in a statement . "But there are some unexpected findings that help provide a better picture of how asteroids and other small bodies form and evolve over time."
One surprise was just how much DART was able to alter Dimorphos. Prior to the collision, the asteroid was oblate, meaning it was somewhat flattened or squished along one axis, likely due to its own rotation or gravitational effects.
After the collision, Dimorphos' shape became prolate, meaning the asteroid was stretched along its axis, making it longer in one direction. The impact likely caused this elongation by redistributing the asteroid's mass and altering its rotational dynamics.
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